It's here! My 3000lb proof that a bite from the CNC bug is incurable!

Can someone here tell me what WAF is? Because it seems to have skipped over me. At work, we design subwoofers and speakers and talk at length about how to make the product attractive to both target buyers and their spouses, who may not want a big black wooden box sitting next to the computer or TV and looking so, um, big.

My wife must really love me! She let me move a 3000 bridgy in and take over the garage. Hmm. Could it have anything to do with the coincidental and simultaneous arrival of a new puppy for her?? Naw, probably not. She must just love me! =)

I am truly excited about this machine! It seems the right deal came along at the right time! I had five basic requirements. The machine had to be:

-local, within a few hours by truck
-Series I size
-originally designed to be CNC
-in good shape,
-Cheap. cheaper than ebay!

And I happened to find it! A local machine shop was getting rid of their Bridgeport Series I, with BOSS3 control. I didn't care if the control was running or not, but it was, and the shop supervisor demonstrated that everything moved ok and ran fine! The price? Well, let's just say that I could easily spend more money on tooling than I did on the machine itself!

Attached are some images of me getting it home. It cost me $75 to get it from the machine shop to my garage. Hiring a truck with a forklift on the back of it really made this an easy process! Others have hired a tow truck to meet them at their house and use their crane to unload the machine. But then you have to pay two drivers, plus tip, of course. =)

I like to keep things together. Here are some related threads I started:


Another thread when I was trying to figure out how to move the machine:
http://www.cnczone.com/forums/showthread.php?t=13216

Questions about which way to go: Just use the existing stepper motors or replace the motors and controllers with modern ones.
http://www.cnczone.com/forums/showthread.php?t=13791

My other CNC machine, the "AKITA CNC" mill. This one is a 4' x 4' router, which will now be much easier to build using the BP!
http://www.cnczone.com/forums/showthread.php?t=11786

I suspect that the puppy is distracting her for the moment.....we'll have to see what happens in 6 months.....

I suspect that the puppy is distracting her for the moment.....we'll have to see what happens in 6 months.....

Hehe. That's when weighing 3000 lbs and being hard to move come in handy! I just have to find and get a lathe in there before the new puppy effect wears off!

But seriously, she's supportive of the project. We won't be able to fit a car in the garage anymore, but I plan to strip and repaint the machine and keep the areas around it looking nice, painted lines on the floor and all.

Actually, retrofitting will be the easy part, since I have three options:
A. Get a rotary converter and use the working BOSS3 controls as-is
B. Strip off the controls, but use the existing steppers with Gecko drives
C. Fit all-new servos and controls

All three options are pretty quick once I make up my mind. Cleaning up the machine will be the really hard part! Take a look at the attached pictures -- it's like an archaeological dig going down through the layers of metal chips that have built up between the control cabinet and the base casting! I will have to completely disassemble it and repaint. Getting the knee off worries me a bit -- it must weigh a ton. Well, not literally, but maybe 800 pounds? I think I'll just go buy a HF engine hoist. It will probably come in handy more than once!

I'm following with interest the thread titled "how to paint a bridgeport":

http://www.cnczone.com/forums/showthread.php?t=13737

Note: That is the same cable in both pictures. One is looking down, the second is looking up!

My NEMA 42 servos are a direct bolt-on replacement on the Z and X axis.

The Y axis is a little tricky because of the limited space under the knee. Including the flange, the motor can't be longer than 8.5". That's a problem for my servos; as you can see from the photo they are too long! If I want to use a my servo on that axis, I'll need to manufacture a new

Servos are right now my first choice for the retrofit, since it means no new cash outlay, and I would not have to build a power supply. Perhaps in the future, I can reuse the stepper motors in another project. Actually, thinking about it, I may have to use the stepper motor on the Y to manufacture a new Y axis motor mount with a large offset to fit the servo. Kind of a boot-strap problem.

In one of the pictures, you can see another serendipity-gone-murphy. The original stepper motors have a 5/8" shaft and 1" wide pulleys with the exact same diameter as some more modern pulleys I have on hand! They even have the same OD! But it was too good to be true. The new pulleys are .375" pitch and the old ones appear to be something like .5" pitch.

Even so, I prefer to replace both old pulleys and the belt, so that I can use my much simpler keyless-bushing-mounted pulleys. If I keep the old pulleys, I need to cut a keyway in my motor shafts. On the other hand, I onyl have 5/8"ID keyless bushings, but the upper pulley needs to fit a 3/4" shaft.

Keyless bushings, by the way are a fantastic! They install without keyways, even on completely smooth shafts and still have the ability to transmit 5x more torque than my 2hp motors can kick out. No gear pullers needed for removal either, just a wrench. McMaster has the 3/4" version I need, but it's $48! And that doesn't include the pulley, just the bushing.

I've been investigating my machine and found these three covers on the head that don't seem to have any purpose, at least not for this model. They are blind pockets in the casting, and don't lead anywhere.

Does anyone know what usually is installed in these holes? Perhaps something meant to go on the manual version of this mill?

30 min Examining all the cables going in and out of the power box.
1 hour Cutting all the cables, removing screwed-on conduit
1 hour Hoisting the box away!
1 hour A whole hour just raking all the remaining chips out, like an archaeological dig!

My new shop crane (engine hoist) made this a much less dangerous job. Who knows how much the power box really weighs, but with all that copper and iron in those huge transformers, it's HEAVY! The hoist is a Harbor Freight special, $150! I suspect I'll be using it over and over again, especially when I get to painting this beast.

To get the box loose, I had to cut all the wires going in and out. Unfortuntately, there were no connectors that I could unhook, so it is a one-way permanent removal. There's no going back now! I included a picture showing all the blue and red wires going from the transformer box to the control box, all unlabeled, of course. =)

I will gut the remaining metal enclosure, which now houses the "brains" of the BOSS3 control. When I'm done, it should be a pretty lean and tidy outfit, housing everything - computer, controllers, breakout board, relays, etc. The swing-out "pendant" control panel will also get a makeover. I'm replacing the mechanical switches with a 14" LCD monitor and keyboard tray mounted to it. Perhaps something like this:

http://www.cnczone.com/gallery/showphoto.php/photo/403/si/panel

But I'm getting ahead of myself. I still have a lot of work just to clean up this beast and get it moved into place at the back of the garage. Originally, I hoped to strip each part down and repaint as I did my retrofit.

Instead, I will clean all the thick grease and gunk off the machine as I do the retrofit, but leave the painting until next summer. For now I'm focusing on getting this machine running and operating smoothly. Once I've made all my mistakes and fixed them, I can paint the machine for that final sense of completion.

It seems so easy - just remove the old motors, bolt-on the new ones. My motors even have the same 5/8" shaft that the old ones do. So this should be a 20 minute job, right?

Wrong. To use the old pulleys would require machining keyways in the motor shaft. And they're odd sized keyways, seeming way too small to transmit 2HP worth of torque. I really didn't want to use their old-fashioned taper-lock pulleys anyway.

Fortunately I'm sitting on a pile of really nice pulleys with modern keyless bushings so I can quickly clamp them onto any smooth shaft - no keyway required! They just happen to be the same 3 1/8" diameter and the same 1" width! So slip the motor in, fasten new pulleys and I'm done, right?

Wrong again! My aluminum pulleys are .375" pitch, but the Bridgeport pulleys appear to be .5" pitch. Ok, fine, so I simply need all new pulleys for the motors. McMaster has them, but for about $150 (for three) - OUCH! And McMaster's pulleys don't have the correct bore for my keyless bushings.

So back to the drawing boar... er.. uh.. computer!

I'm looking for another vendor that has .5" pitch 1" wide pulleys. SDP-SI doesn't have anything above .375" pitch and .5" wide. Any suggestions?

Can a engine hoist really lift a Bridgeport?

Well, last night, I found out the answer -- yes! After removing the control cabinet and disconnecting the final few wires, I slipped the "shop crane" (as Harbor Freight calls it) into place. A handy tip for anyone else trying to move their mill with a shop crane - the 2ton foldable version of HF's shop crane has legs just far enough apart to get around the base of the standard series I main casting.

My son helped me and will probably be telling his friends that he lifted a 1 ton machine into the air with his own arms. He did all the pumping on the hydraulic cylinder, while I monitored all the wheels and ropes to make sure nothing was slipping or about to tip over. When you're pumping on the handle, you can't really see much of what's going on, so I'm glad to have had his help!

Later, my wife stepped in to help me muscle the hovering machine into place. She was definately the brains and I was the brawn -- many of her good ideas of which angle to push at worked out better than my own ideas. I couldn't get it to move on my own, so I would recommend if you try this to have a second person to steer while you push.

So now, it's settled into what I thought would be a permanent location. Now that I see it's not so bad to move it, I can see rearranging the garage some day and moving the mill again if needed.

In a moment of unusual .. uh.. is it bravery or stupidity? Anyway, I stuck my hand under the mill to take a picture. I was all ready to move the mill, had it up in the air, when the question struck me: What is up there anyway?

So I snapped a few shots, hoping the mill wouldn't suddenly drop down and sever my hand. Hehe I used my left hand for the second and subsequent pictures. If you're going to lose a hand, at least it won't be the mouse hand!

I was amazed at how much you could see in there. Parting lines, texture, even flash is all still there, same as it was 25 years ago when they cast this beast. The ribbing appears to be 1/2" thick or so. And it was very cool to see the spider that holds the ram onto the turret. I was surprised there isn't any rust above the height of the foot of the casting. By the looks of it, this was an investment casting, or at least a lost-core casting.

And for those of you thinking "I could never fit a Bridgeport in my garage," I included a picture showing how the garage looks from the outside. The Bridgy takes up no more space than a couple of bicycles and a propane grill.

Who knows, after I clean up, I may be able to fit a few more machines in there!

Taking things apart is easy but we'll see how putting it back together goes in a month or so!

I gutted the electronics cabinet, scraping it clean with a putty knife. It's amazing that this thing worked at all with metal chips, metal dust, and .. are those... ? Yes, someone left pistachio nut shells in the cabinet!! How did that happen?? The metal, dust, and oil, I can understand -- they came in through the vents and around the heat sinks.

I've been dying to try out my cheap-o Harbor Freight sandblaster, which I'm counting on help me clean up the individual parts for painting. It works great, eating up paint and leaving a fine diamond texture. There are a few catches, however. It takes longer than I expected and sand is expensive! $20 for 25lbs of sand. After 1 minute of blasting, I have to wait 5 or more minutes for the air compressor to catch up.

Some guy on ebay is selling plans for an improved sandblaster he calls a "Pressure Assist" sand blaster. It's caught my attention because my current setup is s-l-o-w.

There is a problem with cleaning up your shop (that's another word for "garage" for those of us who haven't yet come to terms with our CNC addiction)

Anyway, the problem with clearing space in your shop is that it makes room for another machine! I'm now the happy owner of a second Bridgeport mill!

This one is a really interesting machine, a "Tracer Mill". The ram on this thing is massive and reminds me of a hammerhead shark. There was real art in the making of these old machines - from the designers to the patternmakers. This particular machine came without a head, but this is more than made up for by the two massive 1.5" diameter precision ballscrews that came with it! The X axis ballscrew alone is likely worth (on ebay) as much as I paid for the whole machine! Some would call that a basket case. I call it a good deal and a new project!

I included some pictures to show a real easy way to lift this machine -- just lift under the head! Worked like a charm to get it onto the truck. When the machine arrived at my house, I learned a valuable lesson: Check all the bolts before you lift!

As we started to lift, I couldn't believe it as I watched a gap open between the ram and the main casting! It hung there in mid-air for a second, then gave way! The main casting slammed back down onto the truck's bed, while the hammerhead shaped ram started sliding down the forks of the forklift, dragging a desperate me with it! As one side came off the forks, it hit the table and began slipping over the edge of the table, threatening to fall all the way to the truck bed, perhaps messing up the Y axis box ways in the process. In one of the pictures, you can see me grappling with it as it teeters! I was just an inch away from letting go (to avoid injury).

In the end, we got it put back together and lifted off. But had I checked the bolts before we lifted, I could have saved myself the scratches on the table, the bent threads in the ram and, of course, a close call. I think the bolts worked their way loose due to vibration during the trip.

Rather than run two seperate logs, I decided to just keep this one log. This should work out nicely, because I will concentrate to finish the BOSS3 mill first, then use it to finish the Tracer.

Could you tell me the size of your Bridgeport after you removed the control and power supply cabinets? I just purchased a Boss 5 online and really don't know exactly how big this beast is after the old electronics are removed.
Thanks Steve

How did I miss this thread?????

Wow - Nice stuff! I guess the 'puppy effect' still hasn't worn off - or did you get another?

Keep us up to date!

Scott

Could you tell me the size of your Bridgeport after you removed the control and power supply cabinets?

The blue tape on the floor in my photos marks out an area about 4'6" wide and 5'6" deep. That footprint will accomodate the mill, along with the original cabinets, even allowing you to open the rear power panel door (which in my garage faces the wall) a full 90 degrees with an inch to spare.

One really nice thing about these BOSS fitted mills is that they were designed for CNC from the start, and since the x-y cutting area is just 12" x 18", the table is only 36" from end to end, and so doesn't need much room.

For comparison, my other bridgeport mill needs a space almost 8' wide because of its 5' long table!

Now, the depth of the footprint can be even smaller if you don't intend to use the original control boxes. If you back the main casting up against the wall, you could probably get it in a spot just 4'6" wide by 3'10" or so deep! The footing of the main casting is only 2' x 3'.

I just measured my BOSS3 mill again and it is 7'2" tall - about 2" taller than my garage door. If your mill is fitted with a rigid ram, you won't be able to just rotate the head out of the way as I did. Others have said they removed the top section of the head to get their rigid ram mills to fit in through the garage door.

Hope that helps!

-D

... Wow - Nice stuff! I guess the 'puppy effect' still hasn't worn off - or did you get another?...

Thanks for the encouragement -- I plan to keep this thread photo-rich, logging anything that might be useful to others doing the same kind of conversion. it's a small way to return the favor to many others whose postings have educated me.

Hehe. No, no new puppies, but my wife did get to go to the Akita Nationals this week in Arizona!

Here's a thread I started in the general machining forum, where I am trying to figure out how I can manufacture my own timing pulleys for my Bridgy!

http://www.cnczone.com/forums/showthread.php?t=14867

Timing pulleys are really priced for industrial consumers, as are servo motors, ballscrews, motor amplifiers and other parts we need. Most of us won't attempt to build our own servo motor -- we just buy surplus or ebay.

But pulleys aren't complicated and the raw materials are cheap -- perhaps $2 for a 1" wide x 3" diameter aluminum pulley. So I got to thinking: 'We're all building CNC machines, and it's near impossible to find an exact pulley on ebay. Why not just make my own?'

The $60 I just spent on one timing pulley seems like money that could have gone toward my 4th axis!

I'm actively soliciting ideas on how to make these gears easily. Jump into that thread and reply if you have any!

Well....if you had a horizontal mill you could use it with some gear hobs to get the pulley you wanted...adding the flanges would then be the most difficult piece. I suspect that once you purchased the correct hob.....the 2nd or 3rd pulley might be bargains....if your time is cheap. I wonder would the hob be an involute cutter......

Couple of comments - I just re-read this thread.

Sandblasting - use paint stripper first. Go to Wally World and get the spray stuff from KleenStrip - it is awesome stuff. This is many, many years of cleaning and painting experience talking here - the sandblaster will work great on hard, thin paint but the thicker stuff just absorbs the impact. Get rid of most of the paint by other means and save yourself some time - not to mention the wear and tear on your compressor.

I would strongly suggest leaving the paint on the main casting! Stripping down to nothing is definately the way to go as far as projects go, but straightening it back out will drive you nuts and take a lot of time. If you have the time, go for it, but if you want to save yourself some serious time, just remove any loose paint and filler, then clean it up and fill only the places you need to then prep and paint. I stripped mine down to nothing and then wondered why in the heck I did that once I started flatening everything back out - it takes a lot of filler and a lot of time!

Those covers on the head are where the quill feed mechanism would go if you had a manual machine head (from post #6).

Keep the updates coming!! (I will do the same on mine when I actually make progress).

I like your commentary and your pics. Good thread!

Scott

Well....if you had a horizontal mill you could use it with some gear hobs to get the pulley you wanted...adding the flanges would then be the most difficult piece. I suspect that once you purchased the correct hob.....the 2nd or 3rd pulley might be bargains....if your time is cheap. I wonder would the hob be an involute cutter......

I don't know much about gear hobbing, but it's an idea I'll have to look into. The teeth on a H-Series timing belt are trapeziodal, instead of involute - flat bottom, straight sides (20 degrees taper per side). I'm getting some good ideas and feedback in that thread. When I figure out which method is best for me, I'll post it here.

I would suggest that you just drop the cash and buy some pullies that will for sure be dimentionally acurate and correct. When making your own, you could have possibilities of not having them super acurate and circular which could become an issue.

Look into the GT2 pullies, they have radial curves and could possibly be done easily vertically.

I have a 15mm GT2 belt and pulies driving my spindle and they work great.

Jon

Couple of comments - I just re-read this thread....
Scott

Hey, thanks for the helpful tips! It took me a minute to figure out you meant Walmart, but I'll follow your advice and get the bulk of it off the cabinet with that Kleenstrip.

Mystery solved -- quill feed lever! Maybe I will mount some LED lights there to replace the bulky machinst's lamp. Maybe it would be a good spot to mount my LCD monitor. Or I may just have fun and machine a new cover with a logo on it. Hehe. That will have to wait until I'm almost finished with the machine. In the meantime, thanks for satisfying my curiosity!

In a way, fixing up an old machine is kind of like that show on HGTV "If Walls Could Talk." I often look at a bent bracket or discover something inside the machine and wonder how it got there or what happened to it. Just look at a table and wonder what it sounded like in the machine shop when the 3/4" cutter started crashing into the table!

I surely will keep up with the updates! The last few days, I've been wiring together the controllers, power supply, and breakout board on the bench. I want to test it out before I start bolting things down. I'll try to sneak the camera from my wife and snap a few photos tonight. Then I'll wade through the 100's of puppy pictures and find the drab gray colored ones and post those!

Once you strip the bulk of the paint and scrape, rinse and dry - the rest will likely blast off easily. It took a buddy of mine to make me realize that I should just use the blaster as a final prep instead of wasting all kinds of materials, time, compressor wear and energy using it to remove everything. Now I will grind/sand/strip/pressure wash as much as I can then abrasive blast to get the nooks and crannies - it's much faster, saves my blasting media and compressor and the end result is the same.

Scott

.....It took a buddy of mine to make me realize that I should just use the blaster as a final prep instead of wasting all kinds of materials, time, compressor wear and energy using it to remove everything. ....

I'm all for learning from other's experience! Your first post convinced me to take the sensible aproach and just patch and repaint the main casting. I blast outside and end up sweeping the wasted sand off the driveway. Why fertilize the lawn with expensive aluminum oxide, when there's a better way?

....Look into the GT2 pullies, they have radial curves and could possibly be done easily vertically. I have a 15mm GT2 belt and pulies driving my spindle and they work great.


I just looked up GT2 in SDP/SI -- and they sure are less expensive. Sort of a rounded-off involute profile; "curvilinear" they call it. The HTD series might be even easier to machine, since it has circular profile teeth; perhaps doable with a simple ball-end mill?

However, I want to stick with H-series for now, so that I only have to replace the 3 pulleys on the motors. If I switch to another pitch series, I have to replace the quill, X, and Y axis ballscrew-mounted pullies and hubs too.

Amazing what kind of support a guy can get on this forum! For the benefit of this thread, this post is a summary of what I learned from my thread about DIY timing pulelys:

http://www.cnczone.com/forums/showthread.php?t=14867

1. There are lots of professional ways to cut timing pulleys. Gear hobbing machines, 4th axis milling, lathe duplicators, indexed cutting setups, and so on. All of these are currently a little out of my reach. Bootstrap syndrome, eh? So I need an even simpler solution to get me started.

2. CNCZone member Buscht suggested I just cut the pulley in 1/4" plates and pin/bolt them together. This is the solution I settled on because it is within reach of the resouces I have available and it will get me up and running!


3. I can get around the problem of minimum cutter size by simply over-cutting the root of the timing pulley groove. This surface is not meant to contact the belt anyway. Since I technically should have a 0.119" diameter cutter, I will just use a standard 0.125" cutter and overcut the groove by 0.006."

Take a look at the attached pic showing how a well-worn H-series belt is shiny on the contact surfaces, but the tips of the belt teeth are still new, fuzzy nylon! That confirms that overcutting won't matter at all, because that surface is a clearance fit anyway.

While waiting for my pulleys, I've been configuring the basic system components on my bench. Before I start cramming components into the electronics cabinet, I want to know they work, after all!

Actually, the test spans two benches, one for the motors (the lower table) and the other for the electronics.

Good thing, too. I'm discovering that mundane details like ground bars and wire routing strategy are not as straghtforward as I hoped. It's amazing how many connections just the incoming AC power requires. Somehow amid this web of wire, I have to route my shielded resolver cables and step/direction wires. There's a lot of opportunity to pick up electrical noise, which, I understand to cause freaky glitches and generally poor performance.

Take the bus bars for example. Ground bars are easy to find at Home Depot; they're the same ones used in a household mains breaker box. In fact, I used three of them -- one each for ground, L1 and L2. But I have a bad feeling about leaving all that energized, exposed metal. It's just asking for a crescent wrench to fall on it! After I had it wired up, I realized I could salvage a copper bar from my BOSS3 control. After cutting into three pieces, it will replace the existing ground bars, which aren't very good at clamping onto stranded wire anyway.

Wire is expensive! In one photo, you see about $200 of wire sitting on the garage floor in coils. 6AWG for running a subpanel, 10AWG for supplying power to the motor amplifiers, and 12AWG to connect everything else. Except the TTL and resolver feedback wires which will be small gage shieled cables. My emerson amplifiers accept step/directon inputs through a 15-pin cable. Rather than buying new connectors and soldering up my own cables, I went the cheap route -- Goodwill! I picked up two joysticks for $3 total, hacked off the cords, and tossed the joystick portion.

Also sitting on the bench are my new 24v powersupply from MPJA.com and a Mitsubishi VFD for running the spindle motor.

yeah D, just stumbled on this thread myself - i've missed a lot!

great machines and a great job recording and posting the progress. The second one is something else, anyone tell you they put the table in the wrong place :D the electrical boxes on that first one are huge - is all that bulk just a result of older no longer relevant techology?

keep the pics coming

... anyone tell you they put the table in the wrong place :D....

Yeah, it's different! Should I want to, I can mount up to three Bridgeport heads on this machine. Originally it was a Tracer mill, used for making copies of existing parts. I'm watching ebay and craigslist for a good used head to come along.

... the electrical boxes on that first one are huge - is all that bulk just a result of older no longer relevant techology?....

Yes, and I intend to stuff everything I need into just one of those boxes. That includes the computer to run Mach 3.

The smaller (but heavier) box is the power box, containing a knife switch mechanism, and all the heavy transformers. To my knowledge, the modern transformers would still take about the same space. But since my newer (mid 90's) controllers have built-in switching power supplies, I don't need the power box at all; I will just pipe the raw 240VAC right into the controllers. They're tolerant of voltages from 90-264VAC and so they don't need a transformer or a power supply.

The control box contained a big power supply, loads of cables, and lots of large, wire-wrapped circuit boards. I've gutted this cabinet entirely and started stripping the paint off today. Thanks to mxtras for the tip on using Kleenstrip to remove paint!

More updates to follow, when I get my final pulley built and the cabinet repainted.

Well, got the Y-axis servo fitted, if only temporarily. It's interesting trying to reverse engineer a 25 year old machine. I photocopied the old iron cover and after scanning it, was able to trace it in Pro/E. But unfortunately, the first try (a paper template) was way off.

My next two attempts were a template in 1/4" cast acrylic (which was way off) and a real part in 1/2" acrylic, both made on a MDX-500 mini CNC mill at work. The last try was close enough that I could get the Y axis servo mounted! It looks nice and shiny, but I know it's probably not going to last forever with a huge motor hanging off of it like that.

My plan is to get the machine limping along on the acrylic bracket, and then machine a permanent replacement out of aluminum. I'll replace not only the cover, but the main pulley housing as well.

In designing this bracket, here's another unfortunate discovery. The "Nema 42-sized" stepper motors that came with the BOSS machine appear to have a different mounting hole pattern than a true NEMA 42 motor. So while I was expecting the Y and Z axes to simply bolt onto the old mounts, I may find myself making even more adapter brackets! Ugh.

The cabinet is about halfway sandblasted, but there's no light at the end of that tunnel -- I have a lot of cutting and welding to do before I can paint it. So for my trial run, the electronics are going to be hanging out on my bench, and not inside the cabinet. My time has been limited, so It is a challenge trying to figure out how to best spend the little bits of it I do have. =) A freezing cold garage doesn't help things either! A lot of other project logs I've been reading here report the same thing. It's hard to get excited about working in a freezer!

Simple green. I think I just found out why they call it 'simple'. For the past few months, I've had it stuck in my head that I would repaint the mill by stripping off all the paint, sandblasting, grinding, filling, sanding, priming and finally painting. Originally, I imagined I'd take the mill apart, down to the bare castings.

Then I discovered simple green works really well and under all that muck is smooth, glossy paint, along with a few areas worn down to the white primer from years of being blasted with steel chips. Simple green removed more than just the muck -- it also lifted a big mental barrier -- that I don't have to repaint right away, that when I do repaint, I won't have nearly as much work as I originally feared. It took about 6 hours of scrubbing, during which time, I used up 3 pairs of khaki pants (cut up into shop rags), halfway filling up my garbage can. My hands are so full of metal splinters, It hurts to run them under hot water! Well worth the price, however.

When I ran out of pants, I figured that was time to stop! This week perhaps I'll finish the job; all that is left is the base and pedestal. The result doesn't look like new, but it sure feels good. Now I can work on the machine for 20 minutes during my lunch break without fear of returning to work with metal splinters in my greasy hands!

The real progress, however, was getting my Mitsubishi VFD wired up and tested, something I have been itching to do for weeks now! Most of the time was spent routing wires up and along the garage ceiling from the bench to the mill. I don't want to be tripping on a rat's nest of wires later!

This is a really sophisticated VFD, with far more funcionality than I'll ever use. The manual is 200 pages. It covers programming quite well, but didn't even hint at how to run it from the control panel, manually. Google came to the rescue and I found an alternative version of the manual showing the "secret" sequence of buttons I had to push. Total time invested: about 4 hours. My reward was the simple pleasure of seeing the motor and spindle hum along for the first time since I got the mill in my garage.

Next, I need to play with the hi/lo gears, variable speed pulleys, and other levers I see on the pulley housing. Hehe. I have no idea what the lever on the left side of the pulley housing does!

I made XL pulleys on a CNC wire; they aresimple on one of them

Hehe. I have no idea what the lever on the left side of the pulley housing does!

On mine that is the spindle brake.

Your mill looks great - time for me to get a bunch of simple green and some gloves.
Steve

On mine that is the spindle brake...

Hey, that makes sense. When I changed toolholders, I leaned on that lever to get the spindle to stay put while I torqued the spindle retaining nut. I just figured it had some other use too. =) Thanks for the tip!

I made XL pulleys on a CNC wire; they aresimple on one of them

That's the way I'd do it too, if I had access to a wire EDM. =)

Just for kicks, here's a picture of the pulley I designed to match my motor (and the Trantorque keyless bushing). I didn't end up using it, but it was an interesting exercise. The pulley is built on a prototyping machine that liquifies, then extrudes plastic, drawing it like a plotter until the whole part is built up. Here's a link to the company who makes the machine, an FDM Vantage.

http://www.stratasys.com/sys_main.html

Last night I got Y axis movement from servo power for the first time! Isn't it funny how giddy and excited a full grown adult can get over a hunk of metal moving back and forth!

This was also my first time with Mach3 and I had a little experimenting to do. You know, like a kid in the electronics department, pushing all the buttons to see what happens, breaking things. =)

At first I was disappointed, it was only moving around 60 IPM. After getting things configured (20,000 steps per inch!!!) I am limited by the 35kHz stepper signal. But at that rate I can get 105IPM, and if I quickly jog back and forth about an inch, I can get the whole machine rocking! Scary thing is that it moves by about an inch at the top of the spindle motor, rocking left and right. Considering that the Y axis doesn't even travel in that direction, I was thrilled to see how powerfull the motors were.

To see how much power reserve I had, I wrote a Gcode program to jog back and forth, then I leaned into the table as hard as I could, trying to slow it down. No dice. It just pushed me backward, shoes sliding on the concrete the whole way!

The motor is 4000 steps per revolution, but once I reconfigure the amplifier to 1000 steps/rev I should be able to do 300-400IPM with enough force to break a 1/2" endmill. Yeah, I know: Finish building before you start breaking things! =) But when you think about it cutting metal with a mill is ALL about breaking things.. into little chips. That's gotta be part of why we love this stuff, right?

Sounds awesome. Just make sure those ways are lubed up really well and you have limit switches!

Jon

Sounds awesome. Just make sure those ways are lubed up really well and you have limit switches!

Good call! I got the way oil on manually, since my Bijur auto-lube is disconnected and a lot of the tubes need to be rerouted. Still have to pop open the way covers and lube the ballscrew.

Before my test run, I could imagine the Y axis running away and tossing itself on the floor in front of the mill! It scares me enough that I hooked up and verified the function of the limit switch before ever turning the servos on.

With the software tweaked near the limit, I decided to to try reprogramming the controller itself. Emerson made a DOS utility for communicating to my controllers via RS232 called PCX. It's a nice utility and lets me configure all sorts of limits, acceleration profiles, and the all-important steps/rev, which I changed to 1000. With a 5:1 screw, this should give me a hardware resolution of 0.0002".

Of course, anything higher resolution than that is senseless, because the ballscrew becomes the limiting factor. For instance, when I was at 4000 steps/rev, it was at a theoretical motor/ballscrew resolution of 0.00005" (yes, half a tenth!)

With that setting changed, what a surprise!! When I jogged the Y axis from the keyboard, it seemed to LEAP across the knee, sending a thump through the concrete when it started and stopped! It was moving at somewhere near 420 IPM, with almost instant acceleration and deceleration! I only did it once, hearing the screw "sing" as it zipped along. Which made me think it's time to shut it down and examine, clean, and lube the ballscrew before I try that again!

Tonight I reached my limit! Limit switch that is!

I've found that Cat5e network cable is a farily inexpensive and convenient wire for hooking up limit switches. With it, I hooked up limit switches for all three axes, along with estop and home. Since the parallel port only allows 5 inputs, I had to compromise by "limiting" myself to one input for each axis plus the compulsory estop. That only leaves one input free, perhaps for spindle index, or for the 4th axis home reference switch. Hmm. Does a 4th axis typically have some kind of home switch?

On the X and Y, the limit switch is double-acting, but when I cut into the original issue 70's vintage wire, I only found 2 wires! The cable was so fat, I expected to find at least 3 conductors, maybe even some extra, unused ones. The quill is a different story, having three seperate switches -- home, Z++ and Z--. Better yet, they are true double-throw switches, although only the normally open sides were tapped. I changed them from NO to NC and then put the Z++ and Z-- in series.

Since Cat5e cable has 8 wires (4 twisted pairs) and most of them were unused, I reserved a spare pair from both the X and Y cables and added them in series with the Z limit switches. In other words, the estop signal goes down the X cable, is soldered together at the end, and loops back to connect to the Y cable, which in turn connects to the limit switches on the quill. I connected this long series chain to the ESTOP input.

So why bother running the estop signal down the X and Y? Just in case. If, for instance, something catastrophic happens and severs one of the cables, my limit switches (which are normally open) will never report being activated, adding to whatever chaos had severed the cable in the first place.

Of course, it's all temporarily slung overhead, each cable about 30 feet long. In the final install, these can be shortened to 10 feet or less. For now, I just want to experiment and find the best electrical configuration. Ok, I'll fess up. I'm also doing it this way because I live in Washington and it's been unending rain for the last... well.. as long as I can remember! Not good weather to paint and finish my electronics cabinet. So this is a shortcut to seeing the machine move.

While testing out the limit switches, I found the source of some of the scary creaking noises the machine makes during fast movements. Originally, I worried the ballscrew/nut were binding or hitting a resonance. But looking closer, the belt is the cause and probably does not have enough tension. So the belt is able to ride up along the side of the pulley until it slips back into the groove, making a creaking noise. Hopefully there is no cogging going on.

Also, I started a related thread about how to remove the way covers on a Bridgeport, and just to keep everything together:

http://www.cnczone.com/forums/showthread.php?t=16323

Finally got around to putting my various bridgeport parts up for auction, almost all the pieces of the original BOSS3 control, including the stepper motors:

http://search.ebay.com/_W0QQsassZamaedQQhtZ-1

Ok, for a little fun, I took a picture of my small MaxNC-10 sitting on the table of my Bridgeport. Soon, I'll be selling off the MaxNC to raise some cash for the rest of my retrofitting fun, perhaps a G-Rex board along with Mach IV for starters.

It's funny how I paid more for that little MaxNC than I did for the Bridgy! Maybe not as funny as how big I dreamed, that I would be hogging out steel with this little toy!

Well, ok, it will only be funny until 5 years from now when I look back at my Bridgeport and laugh at my [present] self. Maybe I'll have a whole machine shop by then, pieced together and retrofitted in the DIY Gingery bootstrap spirit! Or maybe I'll be sitting on a nice VMC, having stepped up to the profesional versions of my BP "toy!"

Hmm. No, the more likely reality is my garage will be totally cleaned out. My wife will tire of my wanna-be machine shop and have 'asked' me to clean it up. Instead, she will have 6 dog kennels and a dog-business running out of my garage. Only then will I look back on today and long for 'the good old days' when I could satisfy my mechanical curiousity.

As another CNCzoner' aluded to, we'll see how long this "puppy effect" lasts. So far, so good. I'm still working on a strategy for the lathe. What lathe? Oh, the lathe I am dreaming to build/buy. =) But first things first. I gotta get this one running!

The next challenge is mounting the servo motors to the Z and X axes. Only two of my NEMA 42 size servos have a 5/8" shaft. The third NEMA 42 servo has a 19mm metric shaft, aproximately 3/4". Since I don't have any Trantorque bushings (keyless bushings) in the 19mm size, I can't use this third motor quite yet.

So logically, I should put the two stronger motors on the X and Y axes and use a smaller 1HP servo on the Z axis, since it is only accellerating the mass of the quill and toolholder. But there's a problem, the 1/2" shaft on my NEMA 34 sized servo is too short to mount the pulley. Add an adapter plate into the mix and the shaft barely sticks past the mounting flange. The adapter is needed to accept the locating ring on the NEMA 34 motor, as well as to mate to the legacy hole pattern on the machine.

I've got an idea brewing, to make a custom pulley that extends upward through the flange and adapter plates...

Between work and a kitchen remodel I managed to scrape together enough time to make a prototype bracket on another CNC machine available to me. I'm holding the workpiece (cast acrylic) down with double-sided tape. Actually, the picture is of a NEMA 42 to legacy adapter. The NEMA 34 version will be the same thickness, about 12mm (1/2").

Ok, I've got a new direction for the Z axis. I've switched to the smaller 750w servo for the Z axis, which should still be overkill.

The "shaft extension box" houses a 5/8" shaft and two bearings. It makes the connection to the motor via a flexible coupling. And the pulley is mounted to the shaft with a Trantorque keyless bushing (man, I love those things!).

But this does more than extend the shaft (see previous post). It gives me more freedom to adapt the old 3.5" bolt pattern to the new NEMA 34 motor. No matter what scheme I tried, I could not get the motor shaft to stick out far enough to align with the other pulley, partly due to the adapter plate thickness. Trying to make that plate thin and having the motor immediately on the other side really limited my options for changing the bolt pattern.

Another benefit of this design is that it takes all the side-load forces off of the motor. The belt tension forces are taken up by the pair of cheap bearings (even more fun if you get specific and say "cheap skate" bearings). And any misalignment is tolerated by the flexible coupling.

And the final problem this solves is my 1/2" shaft on the .75kW motor. I have plenty of 5/8" ID keyless bushings that fit the $60 pulley I had made. I also have 1/2" keyless bushings, but they don't fit my pulley, and a new one would be another $60. So I just order a flexible coupling that has 1/2" bore on one side and 5/8" on the other!

I've been busy these last few weeks remodeling my kitchen, which still isn't finshed. And I'll be in Hong Kong and China next week. So that puts a damper on building this for a few weeks at least.

On the bright side, I'll be touring a few toolmakers (mold makers) and will be paying close attention to their VMCs that they're always so proud of showing. Actually, I've seen them many times in the last few years, but until this past year I wasn't too interested in CNC. Their big machining centers were just another waypoint on the tour.

One funny thing about China is that they have machine shops that spill right out into the sidewalk. Driving along a street, you see a restaurant, sports store, book store, tea shop, and then a machine shop, two rows of bridgeport knock-offs 100 feet deep (what's that, 10 machines each row?). We put machine shops in industrial areas, and like our strip malls to be about shopping. In China, steel fabrication, motor repair, motorcycles and bicycles just sort of spill out into the streets. =) I'll see if I can get any pictures while I'm there.

It was a very productive trip to Hong Kong and China, and now that I'm starting to overcome my jetlag, it seems appropriate to follow through with my promise to post a few pictures! All of my HK (Hong Kong) associates thought it very funny that I was on the hunt for a picture of a machine shop next to a restaurant, next to a clothing store, next to a hotel. I didn't capture that picture exactly, but I did snag a few pictures that hopefullly illustrate how industrial and widespread machines are, especially in the southern (Dong Guan) area of China.

In the USA, you would never see a machine shop tucked into a strip mall between Target and Baskin Robins! However, in China, this kind of technology belongs everywhrere it seems, spilling out into the streets in a way that must seem quite normal to the residents there. To me it was kind of exciting, since I've recently been bit by the CNC bug and coming to terms with my fascination with machines!

Here are just a few of the pictures that I managed to take from the inside of a moving van. There are some other interesting ones of China in general. I'll start a thread in the CNC Clubhouse forum in the interest of not side-tracking the thread too much.

http://www.cnczone.com/forums/showthread.php?t=18002

I can't post a lot of the most interesting pictures from inside our factory, for instance, pictures showing our specialized molds for new products. It's enough, however, to get a feeling for the place where all your import mills were born! =)

Hi,
I just joined this site yesterday and am folowing your posts about your Brideports. I live in Issaquah and just aquired a Comet 3Kv That was a cnc machine. It still has the X & Y servos but no controler box. I was going to convert it to manual but after finding this site I have "gotten the CNC bug". I know nothing about what it would take to bring this beast back to a CNC machine. If you are close to the Seattle area I would like to get together sometime and maybe you could point me in the right direction. Thanks, Jack....425-442-6126.

Hey, welcome to the site Jack! I'm in Vancouver, across the river from Portland, but I'd be glad to share ideas or visit if I'm in Seattle or you're in the Portland area.

I'm no expert, but like everyone else here, I'm learning by doing. Most of what I know about CNC is from reading on this site or else from making a mistake! For instance, tonight I've been working on my Z axis broke a tap off in an aluminum plate I had about 3 hours invested into. So I ground it off and I'll just do without one screw! =) Actually, that's not my style, to just hack something together. But I found a good mom & pop metal recycler where I can get aluminum for $1 a pound! So I'm making do with raw materials that are "previously owned" aka "used."

See, that was another mistake -- I'm spending a lot of time making these parts, but I cheaped-out on materials and ended up with a lot of extra holes in my brackets. And I'll end up with more waste material because I have to position my part carefully in the raw material to avoid as many holes as possible! So I saved $20, but someday I'll have to rebuild all these brackets using good material. Hehe. That's the sort of thing that I'm learning.

If you have a picture of your mill, upload it here, I'd love to see it. If you already have servos attached to X and Y axes, then it would probably be more work to convert it to manual than it would be to make it an operating CNC again. You'll have to upload the motor specs (maybe a nameplate photo) to the Servo forum on this site. Those guys can help you identify your servos and probably tell you which servo drives will be compatible. Anyway, upload a pic or two and we'll all try to help out =)

Hi damae,
I don't have the mill home yet, just the head to work on it. I think I know how I will get this 3500 lb. beast home (it's about 8 miles away) but I am still working out the details. I hope to have it home by next friday. I stated it has the servos because that's what the former owner told me but maybe thay are steppers? I think the machine is a 1985. Anyway I will post pics when I get it home. Being new to this board I'm thinking I should start my own thread to post the pics. Keep in touch, Jack.

I look forward to seeing your thread! How to move the mill is the first DIY challenge, almost like a test! If you are determined enough and manage to figure out how to wrangle a full-size mill to your house, then you've got what it takes to refit your mill!

Extra points if you get it in the garage before the wife notices!

(double extra points if she finds out but lets you keep it)

Amid trips to Hong Kong, working double-time and remodeling the kitchen, it's amazing, but I managed to find enough time to build some of my Z axis adapter. The design changed to accomodate the parts I sourced:

-1/2" to 5/8" helical coupler from McMaster (they had the best prices!)
-Recycled bearings with nifty built-in shaft collars (from my junk pile)
-5/8" shaft, also recycled from my junk pile.

The pictures show the Z axis motor bracket being machined, and then the finished product. This is the top plate of the 5 parts in the Z assembly. These are also the first aluminum parts I've cut for this machine. So far, everything else has been cut from cast acrylic. Our little Roland MDX-500 at work has incredible accuracy and control, but it is way underpowered for making big stuff out of metal. It was painfully slow watching these brackets get milled out with a 5mm end mill cutting just 0.2mm deep per pass! And this mill is fast compared to my little toy MaxNC. I'll be selling that little MaxNC soon here, by the way.

Anyway, I can't wait to see what 2HP can do! Were I smarter, I would have focused on my X axis first, then use X and Y to build the Z axis parts. So after I have the Z done, I will have Y and Z only. Not too useful yet. more pics to follow.

EDIT: The third picture shows the parts laying on top of the assembly drawing. I still have 4 more brackets to machine!

Alright, I knocked out the two side plates. They'll be functional, but not very pretty.

$1/lb is cheap for aluminum. But if you end up scrapping half of the material due to pre-existing holes, then you're really paying $2/lb. Brand new material can be had for that price! So the lesson? If you're buying scrap, resist the temptation to buy a piece with holes in it, no matter how nice the piece otherwise seems!

So from now on, I buy clean scrap only! The scraps aren't entirely wasted -- I can sell it back at $0.45/lb or I can melt it down myself to use in castings. The place I go to has some nice 1"x6" bar cutoffs. I'll try to grab more of that stuff whenever I can.

Next update I should have the two bearing supports finished.

Alright, I'm looking for some advice. I bought a set of 5 shell mills with a 3/4" hole to fit a shell mill holder I already have. In the auction, they were described as used, but in good condition. Those of you with experience, please take a look at the cutting edges (I provided closeups) and tell me if these cutters aren't shot!

To me, they seem unusable. Am I wrong? Is there a way to grind down the cutting edge and recycle the cutter? These are not replaceable inserts, by the way.

Ouch, I hope you got those cheap. They don't seem to be in "good" condition to me...

I am a big fan of replaceable insert tooling...

Although I did just buy some 60 and 45 degree american made dovetail cutters on ebay that will have to be thrown away when worn...but they were new old stock...

Ouch, I hope you got those cheap. They don't seem to be in "good" condition to me...

Yeah, I wouldn't have called that "good" condition either. Would have been a fair deal if they were usable.

Any chance I can grind the chips out? Anyone know where I can go for new tooling, good prices on shell mills with inserts?

Well, I hacked it together, finally. The completed assembly weighs so much that it counterbalances the entire servo motor when sitting flat on a table, even though the servo motor is cantilevered above the table!

So perhaps the scale of the aluminum plate was a bit overkill. I ended up with 1/2" (12mm) for the sides and top, 3/4" (19mm) for the center bearing plate, and 1" (25mm) for the bottom plate. I went with thicker plates to accomodate the 1/2" thickness of the bearings.

With everything buttoned together using stainless SHCS's (socket head cap screws), the assembly seems to do its job very well! It achieved my goals:

-extend the shaft
-relieve radial stress from the motor's shaft
-Allow mounting to the non-standard (non NEMA) BP stepper motor bolt pattern

Pics show it on the machine. Turning the shaft by hand, everything aligns beautifully, the belt centers itself on the pulley. The pulle clears (barely) the heads of the 3/8-16 SHCSs. And the whole setup is future-proof. If I want to switch to NEMA 42 (or anything else for that matter) then it's a simple matter to add new holes to the top plate.

Comments are invited, if anyone sees something I'm missing, or wants to see more of a detail I missed.

I had a productive shopping trip at the junkyard!

Check out the new enclosure I found for my LCD monitor. It's already got 22mm holes for standard switches and a cutout that is exactly the right size for my little LCD screens (14" I think). The inside is very nice with enough room for the computer. Since the rear door and enclosure are waterproofed and hence somewhat airtight, I'll have to be carefull to give the computer enough cooling.

Another mystery solved: What is the professional way to connect all of my devices to L1 and L2 AC power? A few months ago, I was pondering this very problem. I just ended up getting a few grounding bars from Home Depot and screwing them to a 2x4! Not the safest configuration, even if it was temporary.

The bus bars (shown in the pictures) were a little bonus that came with my new scrapyard enclosure! Yes, I am finally abandoning the original Bridgeport cabinet, after all that stripping, scraping, sanding, sandblasitng and planning! The new cabinet is full of panduit and already has DIN rails mounted. There's a floating sheetmetal mounting board that will make it easy to mount the servo drives. The best part, perhaps, is that it is already painted!

Don't worry, I make it that easy! I'm going to elevate the cabinet off the with a welded stand with wheels. *sigh* I guess that means I'll at least have to paint the stand. No escaping the paint!

In a bid to clean-up the garage a little, I finally got around to moving the tracer mill away from the garage door and closer to the other mill. Again, I used my HF shop crane, but this time with a nice fabric lifting sling. The sling worked out a lot nicer than the tangle of nylon rope I usually weaved when trying to lift a mill!

Nice trash pick! I am jealous! That looks like a fantastic enclosure.

As far as your cutters - you can probably get the tips replaced. I am sure you have a tool grinding shop in your neck of the woods - some charge a ton for this kind of thing and some aren't all that bad. My guess is maybe $60-$80 per mill to get them fluffed back into shape so it may not be worth it - but that's a guess. The other option would be to get the carbide out of there with an OA torch and convert them to an insert style cutter. If you have an indexing head you may be able to do that on your mill. If nothing else, they will make good paper weights....

Looks like you are making good progress - keep it up!

Scott

What a great find. I am going to the scrap yard today where I found two 3ph motors to look for a electric panel enclosure. With any luck I may even find some usable components. Wish me luck. Jack.

Thanks guys, I was pretty happy with the "scrappin" trip! My wife is into scrapbooking, but she has an entirely different idea of what a good shopping trip at the scrappin' store is!

Jack, I hope you find what you need! It took me more than one trip to find a scrapyard that carries the kind of junk I want, so you're fortunate to have one nearby. You should be near the Boeing surplus store too, aren't you?

I find that if a scrapyard receives high-tech scrap, then they usually don't want to disclose which company the scrap came from. So I am guessing that we can't just call Intel and find out where they take their scrap! So the only way to figure out where the scrap goes is to go visit all the scrapyards!

Scott, good 'tip' on the cutters. (pun intended) It's hard to find good shell mills on ebay with a 3/4" arbor hole. I thought they were going to be paperweights, but when I looked up prices on regular shell mills, I realized that sharpening these tools may still be the way to go, even at $80. I only need one good sharp cutter. The rest can be paperweights. =)

Hi damae,
Just got back from the scrap yard with a few goodies. A 3 leg disconnect complete with fuses and a relay box with 2 solid state relays ,3 mechanical relays, 2 limit switches and misc. on/off switches and busses. I also found some transformers but didn't know what sizes I need. Jack

Jack -

You can not post stuff like this without posting a few pics. It is completely against the rules.....

:stickpoke




:D

Scott

man, why cant we have scrap yards like that near my house? those are some great finds, keep up the excellent posts!

Didn't mean to tease. Here are some pics of the two 3 ph. motors found last friday and the boxex I found yesterday.
Total cost for all items (not including the mill they are up against) is $35. $10 ea. for the motors and $15 for the boxs. The motors havn't been tested yet ( needed the disconnet for the test station) but I suspect the red 7 1/2 hp. one was discarded because of a broken end cap (I will make a new one) and the blue 15 hp. one discarded because of a broken internel fan blade I will fix.

Whoa! 7.5HP and 15HP motors! What are you going to do with those? If its for your spindle, that's overkill... I like it!!

Hi Da mae,
I will use one or the other of my finds for a phase converter. My mill has a 3 hp. spindle motor, hence my need for a phase converter. I hope to get my test station set up soon to see which if either of these motors I can use. The 15 hp spins at 3525 rpm and the 7 1/2 hp. spins at 1165. If they are both good motors which would be the better choice to use? Jack.

Hi Da mae,
....The 15 hp spins at 3525 rpm and the 7 1/2 hp. spins at 1165. If they are both good motors which would be the better choice to use?

I'll be interested to see how your phase converter turns out! You may try the phase converter/VFD subsection forum on this site. I'm no expert on that sort of thing =)

http://www.cnczone.com/forums/forumdisplay.php?f=273

Tested my homebuilt phase converter last week with the 7 1/2 horse motor. It works. The motor needed a new end cap so I made one on a friends lathe and bridgeport. The end cap was my most complicated project in my new hobby so far and it turned out great. I tried the 15 horse today and it works too but I blew a fuse after a few seconds (I forgot to take my finger off the start button after the motor started). While it was running I detected some bearing noise so I suspect thats why it was junked. Will get new bearings. Jack.

Sure, lots of people get their X and Y axes working, then run their CNC in 2-axis mode to make their Z axis mount.

I guess I'm a little backward. I got the Y and Z mounted first, then used the mill in SINGLE AXIS mode to make the final cuts on my X-axis bracket! Actually, I built the bracket on a small CNC mill at work, but forgot to make a clearance cut on the backside. So I decided to give single-axis cutting a try and hope that the cutting forces don't back-drive the ballscrew on the X or Z axis.

Well, "the force(s)" were with me! I'm happy to report that I successfully made my first real cut with my CNC mill, driving a 7/8" end mill through the material at about 40IPM with a cut depth of about 2mm (0.080"). It was a full-width cut. The result was beautiful. The machine didn't even grunt. It just enjoyed its lunch, flinging giant 6's and 9's at me.

Yes, this does indeed call for the dancing banana! :banana:

Isn't it funny how just when you seem to have finished something, you find out that you don't have the right bolt? I really wanted to bolt the motor on as soon as I had the bracket, but something wasn't fitting quite right. I couldn't pull the motor down far enough to get the bolts into the bracket.

It turns out I made a bad assumption. The Y axis uses a 18 tooth pulley, and the X axis looked the same. So I paid misumi another $40 to make me a pulley for the X axis, only to find out that it's just an expensive paperweight. Acutally, it will be a spare for the Y axis. Still, it meant another delay.

So I found the correct 16t sized pulley online at Misumi and downloaded the CAD model. I used Misumi's 3D model to build the part on a prototyping machine out of PC/ABS. The part took 4 hours to build, and I was up and running again!

So now with the correct pulley, everything fit perfectly. With all three motors mated to X/Y/Z, I am ready to move the electrical components into a more permanent home, mounted in a proper cabinet. That's the next step.

Jack F Check your neighborhood electric motor shop most have piles of fan's and end housing's from burned up motor's or watch the salvage yard's seem's socaled junk motor's are 15to20cent's a pound at the scrap yard Good luck Kevin

Hi Kevin,
Checked the local shops and found zip. Made a new end cap for $10.00 and it's 10 X better than the factory unit (heavy bittet vs thin cast). Paid $ 10.00 for each motor and they both work (15 hp didn't need a fan, the bearing retainer was loose) although the 15 hp may need bearings. Side note; there is a place south of the Seattle area with tons of scrap motors but they won't sell them because they rebuild them. From what I understand they couldn't rebuild all of them in the next 100 years. Go figure!

Got the drives and VFD mounted to the back panel.

Yeah, the cabinet is a bit overkill, bigger than I really need. But wire routing should be very clean with all that Panduit! I could hardly maneuver the backpanel into place after I mounted the drives, because of the weight and awkwardness of it. It's just 18gage steel and the components, but trying to wrap my hands around the sheet metal edge makes it difficult to lift. So I may install some lifting handles!

The cabinet is NEMA 12. Or rather it _was_ NEMA 12, before the previous owners put all those cutouts into it. I am thinking to seal those holes with aluminum panels and some double-sided adhesive. If this is a bad idea, or if anyone has a better way, please let me know!

Also, I plan build a metal stand for this cabinet by welding tube steel into a box frame and mounting it on steel casters. I like being able to move the cabinet around to clean around the machine. It will also make transportation of the mill a lot easier. For now, it's sitting low to the ground on a wooden Harbor Freight movers dolly. At $15 each, those dollys are great for keeping all my heavy shop items movable!

I bolted a spare piece of aluminum extrusion to the backplane to serve as a shelf for the computer. Small bungee cords hold the computer in place, but allow easy removal for servicing.

I located the breakout board close to the computer and added some small DIN-mounted terminal strips for easy setup.

And if you look carefully, you can see the handles I added to the backpanel on the door side. They were scavanged from 8020 aluminum extrusions at a scrapyard, and very handy!

damae nice work

damae nice work
Thanks! The wiring is one of those simple jobs that turn out to be very time consuming. I find most of the time is spent trying to think ahead and make sure that I don't route the power wires anywhere near the signal wires.

I am actually further along than that last picture shows. Today, I got all the signal wires, and most of the power wires routed into the cabinet. I'll post pics of this tomorrow. I'm sure that as soon as it's finished, I'll start spotting things I should fix and change. For instance, I'll have to rethink how I have the wires entering the cabinet. When i start cutting steel and using coolant, I will need to completely waterproof the cabinet somehow.

But for now, I'll be happy to see the first draft working!

At the last minute, I scrapped my plan to extend the original spindle motor cable, since it was looking a bit tired. The Z axis motor also needed a wire run, so I put down another $60 for power cable: 12AWG/4 conductor and 14/4.

As of now, I have all three axis motors wired for both power and signal. The matching connections on the servo amplifiers are also routed and hooked up. The computer, mouse, keyboard, and breakout board are all connected.
All of the power cables have started to add up to a really thick bundle, especially where they run along the left side of the cabinet. Notice that all the signal wires enter from the opposite side, as far away from AC as possible.

Still left to connect:

1. Spindle motor
2. Limit switches (already routed, but not yet connected)
3. Main contactor
4. Power from the breaker box

While it may not sound like cause for excitement, anyone who's been there can probably remember the anticipation and excitement as you tried your first cut under CNC control!

I'm making the mill build itself in some ways. This first cut was very simple -- just enlarging a crude hole by about 0.080". As excited as I was to make all the final wiring connections, I was stalled by the spindle motor connection. My new conduit connector would not fit the original hole on the wiring box that mounts to the spindle motor. So I rigged it up temporarliy so I could run the spindle motor long enough to make this one cut. Worked beautifully, once I debugged my simple handwritten gcode program.

Don't look too carefully -- I know I'm clamping the part in the vise without any jaws! Soft jaws are on order =)

It's crazy, but I managed to shoehorn about 15k lbs of iron into my standard 20'x20' garage! The two original machines (both Bridgeports) are the subject of this tread. But since they'll be sharing space with the new mills you will be seeing them in the background photos of this thread anyway. Might as well introduce them now!

Why four mills? First, I've been wanting bigger and better. When I came across a couple of fantastic deals, I couldn't pass it up! Ultimately, my goal is to clean, repair, and retrofit 3 of the 4 machines and sell them once they are restored, improved, and capable machines again! The fourth machine will always be manual. It's just too cool as a classic! At the end of my adventures, I want to sell them for enough to end up with just one very nice milling machine, maybe a small VMC.

Mill #3 is a Shizuoka AN-S with Fadal toolchanger and Bandit controller. It weighs about 5kip and once assembled will require cutting a small hole in my garage ceiling to accomodate the power drawbar! If you're not familiar with the term "kip" it stands for "thousand pounds," (usually pounds-force).

kip = kilopound = 1000lbf = the weight of 1000lb

I had to remove the Shizuoka's head to even get it through the garage door! Putting it back on will be interesting, since I don't think my HF shop crane can reach high enough. The toolchanger is missing its arm and the controller is shot. I'll replace with all new electronics.

Mill #4 is an old Kearney & Trecker universal mill, meaning it is both a horizontal mill and a vertical mill. I love the styling of the castings, covers, head and doors. There's something very satisfying about the tactile feel of all the levers as they lock into their detent positions. The motor, flywheel and all the powerfeed drive shafts are completely enclosed and housed in the main turret! This one I'll simply clean up and perhaps add a DRO. I like the way it looks without going CNC. I have a 6" face mill and arbor to mount in the 50-taper horizontal spindle. Yeah, 50-taper! This is one big machine. At a minimum, it's 6000kip.

When I start a new thread for the Shizuoka, I'll edit this post and add a link. In the meantime, here's a link to a thread where I wrestled with how to squeeze the mills into the limited space:

http://www.cnczone.com/forums/showthread.php?t=20589

The last picture doesn't do it justice, but if you look really carefully, all four mills are at least partially visible in one garage!

Since my last post, I have been to Hong Kong and back. I'll be going again in about a week! So work has left little time for the CNC hobby.

Still, I managed to get a few things done. My first goal is to finish the Z axis on the Bridgeport, since the used servo motor/controller combination didn't work very well.

Here is my overall plan of action:

1. Get the new servo motor mounted which requires...
2. Machining a new servo mount, which means I need to use my new ER32 collet chuck. Which doesn't fit because of the oversized flange.
3. Turn down the flange in a lathe...
4. Buy a lathe... (done)
5. Buy a toolpost because the lathe didn't come with one.... (done)
6. Use the Bridgeport in 2-axis mode to make the toolpost's T-nut fit the lathe... (done)
7. Mount the toolpost.. (done)
8. Buy some turning tools... (done)
9. Buy a rotary phase converter to run the lathe... (done)
10. Install the rotary phase converter....

See how one simple task leads to another? Installing the RPC will have to wait until after I return from my next HK trip. The lathe is a 14 x 42 Sheldon, with a new quick change toolpost and I'm very excited about this addition to my shop.

I also bought MeshCAM to generate gcode. I'm really impressed with it so far!

Edit: I had lots of pictures to share, but the upload.php script seems to be malfunctioning. I'll try again later. (perhaps the CNCZone admin is having the same one-thing-leads-to-another syndrome with the forum that I am with the mill! =)

Forgot to add a picture of the lathe:

Progress comes in small steps lately!

-Installed 240v outlet next to the mill (to get rid of 10/4 wire draped along the ceiling!)
-Designed a NEMA 42/NEMA 34 combo adapter for the Z

Unfortunately the part I designed is about 7" square (and 1/2" thick). 6" stock is easy to find, but I've gone home empty handed from the scrapyard on my last few trips. I was thinking of buying from these guys on ebay:

http://stores.ebay.com/ACS-STEEL-COMPANY

Their prices are actually very reasonable, and they'll even cut the outside shape for you. Has anyone from the 'zone used them yet?

Damae,
Keep the pics coming. You seem to be attracted to these excellent deals. Will the garage floor support that weight. :)
We will be watching as your efforts unfold.

Jason

Lots of questions. As a noob, I have questions which I haven't even formulated yet.
1) You opted to replace the stepper motors with servos. Elsewhere, I read that servos are considered by some to be a second-choice option, particularly when integrating with Mach3. Why did you choose servos?
2) How do you power the cnc controls? Are they run on a separate 110v circuit, or are they run off the three phase power coming from the vfd?
3) In your situation, is there a reason you chose to run a vfd for the Boss as opposed to a RPC? Have you integrated the CNC controls with the vfd for programmatic speed control?

I would like to do exactly as you have done, except I would have a bias toward keeping the stock servos (absent a compelling reason to dump them e.g. incompatibility with controller or software), and I'd like to have one RPC run both the mill and the planned lathe. At this point, I don't see the clear necessity of a vfd in my situation.

Hi Lumberjack Jeff. Good questions; see answers below:


1) You opted to replace the stepper motors with servos. Elsewhere, I read that servos are considered by some to be a second-choice option, particularly when integrating with Mach3. Why did you choose servos?

Servos are actually much better performers, especially in speed, and control. For instance, most steppers systems are open-loop, which means that if you have a momentary load that is greater than the power the stepper is putting out, the control has no way of knowing that position is not what it is supposed to be. Aside from losing steps, steppers typically lack speed, whereas servos commonly are rated for 3000rpm.

Of course, there are ways to add an encoder to a stepper motor to prevent missed steps. And modern micro-stepping controllers are much better than the original BOSS control. So even though the original BOSS control would have 1 step = .001", a new GeckoDrive could easily get much finer resolution.

On the other hand, Servo controllers usually have a lot of extra features packed in, like programmable acceleration profiles. The Emerson units I'm using allow me to select (in software) what resoultion I want the motor to operate at. I can tell it to be a 5000 count/rev motor or a 100 count/rev motor.

But the biggest reason I switched to servos was because I could replace older steppers with much larger servo motors and get better resolution, speed, and power. At the time, it looked like the servos would be bolt-on replacements. Of course, reading my project log here, you see that I ended up needing custom motor mounting brackets to make it work.


2) How do you power the cnc controls? Are they run on a separate 110v circuit, or are they run off the three phase power coming from the vfd?

That's another advantage of the Emerson servo controllers. They have their own power supply built-in. All I do is supply 240v single phase and it rectifies it and generates its own 3-phase motor power. Pretty simple. I didn't have to build any power supplies, as I would have if I kept the original steppers.

I was too far down the servo path before I realized how simple it is to convert a BOSS to run off of Mach. That would have been a true shortcut. It might have been a better first step, because I could use that setup to machine all the parts I needed to convert to servo control.


3) In your situation, is there a reason you chose to run a vfd for the Boss as opposed to a RPC? Have you integrated the CNC controls with the vfd for programmatic speed control?

Yes, but in the end, some of the reasons are flaky:

1. I didn't want to buy a RPC, too much money. Funny thing is I just bought one to run my lathe and the other mill (Kearney & Treker). So had I just committe to a RPC to start with, I could have reused the original power supply and stepper drivers and just plugged it all into Mach, using the MaxNC mode.

2. VFD allows you to run the motor even faster (or slower) than 60hz. The motor can probably handle 2x the speed safely, but the spindle bearings ultimately limit the max RPM.

3. Spindle speed control from Mach was the ultimate goal. I don't have that hooked up yet. (it doesn't take step/direction signals)

4. The VFD allows me to run the whole machine off of single phase 240v power, and I got to ditch the original motor starting controls (another metal box hanging off the mill)


I would like to do exactly as you have done, except I would have a bias toward keeping the stock servos (absent a compelling reason to dump them e.g. incompatibility with controller or software), and I'd like to have one RPC run both the mill and the planned lathe. At this point, I don't see the clear necessity of a vfd in my situation.

Were I to do it all over again, I would have just bought a RPC and a set of Geckos. Later I would have redesigned the machine and have it build its own parts. Leaving the stock motors on has a huge advantage, because you don't have to mess with belt tensioning, motor clearances, motor wiring, etc. And after all, those motors were sized for that machine... back in 1975! =) By all accounts (see elsewhere on the 'zone) this method works beautifully!

Damae,
Keep the pics coming. You seem to be attracted to these excellent deals. Will the garage floor support that weight. :)
We will be watching as your efforts unfold.
Jason
Hey Jason, thanks for showing interest in my thread! =)

I do have about 15,000lbs of machine tools in there. But a coworker just put it in perspective for me yesterday: his Suburban weighs 10,000 lbs, but that's sitting on only 4 contact patches!

Yesterday, I was in a molding factory in China, where they had about 25 injection molding machines in a row, on the second floor of the building. These machines easily weigh 5tons each. When one of the employees accidentally dropped a 500lb mold onto the ground (from about 1 foot) the whole floor shook and it really made me think about how amazing it is to have so much weight up on the second floor! Then again, no more amazing than a parking garage really. =P

Anyway, I think my garage floor will be OK. No threat of putting any more machines in there -- they just won't physically fit!

I was too far down the servo path before I realized how simple it is to convert a BOSS to run off of Mach. That would have been a true shortcut. It might have been a better first step, because I could use that setup to machine all the parts I needed to convert to servo control.
(snip)
Were I to do it all over again, I would have just bought a RPC and a set of Geckos. Later I would have redesigned the machine and have it build its own parts. Leaving the stock motors on has a huge advantage, because you don't have to mess with belt tensioning, motor clearances, motor wiring, etc. And after all, those motors were sized for that machine... back in 1975! =) By all accounts (see elsewhere on the 'zone) this method works beautifully!

Thanks so much for your thorough reply, this thread will be an excellent resource for those contemplating similar conversions.

You mention, and I've read elsewhere, anecdotes about others who have performed conversions using the existing steppers. As I understand the ways to use a 80's vintage BP with a Boss controllers, in order of complexity;
1) use as is (and with its limitations) and repair electronics with scavenged but expensive parts
2) hook a pc up to the existing boss controls via rs232 to store and organize programs
3) replace the boss electronics with new stuff. I've read that the Geckos (201's?) won't handle large stepper voltages, apparently the steppers that came with the BP are under this threshold?
4) replace the boss electronics and the original steppers.

In your research, have you seen a discussion from someone who took door #3? If so, could you provide a link? (I've googled my fingers to the bone trying to find one ;) )

Also, I'm not that far from you. Where did you find your machinery? The Seattle area seems to be (except for boeing) devoid of any machine tool selling activity. I suspect it's because of the sales tax. Any recommendations for someone trying to get started?

...
3) replace the boss electronics with new stuff. I've read that the Geckos (201's?) won't handle large stepper voltages, apparently the steppers that came with the BP are under this threshold?

In your research, have you seen a discussion from someone who took door #3? If so, could you provide a link? (I've googled my fingers to the bone trying to find one ;) )

Also, I'm not that far from you. Where did you find your machinery? The Seattle area seems to be (except for boeing) devoid of any machine tool selling activity. I suspect it's because of the sales tax. Any recommendations for someone trying to get started?

Hi Jeff,

I did a quick search and found a few others doing Gecko conversions with existing steppers (Door #3):

http://www.cnczone.com/forums/showthread.php?t=23079
http://www.cnczone.com/forums/showthread.php?t=23605
http://www.cnczone.com/forums/showthread.php?t=19637

There are lots of others who have posted diagrams and instructions on how to wire a gecko to the OEM Bridgeport steppers. This may have been a smarter route to go, but I'm happy so far with Door #4. =)

It's funny you mention a lack of machines in the Seattle area, because I bought my last two mills from Arlington, just north of Seattle. Watch Craigslist and ebay (sort by distance). I find that weeks may go by with no listings. Then all at once, there will be a flurry of unrelated posts offering mills. Patience pays off big time! That and being the first guy to come out and take a look at it.

Faced with the prospect of scratching out my missing aluminum motor mount on a very small CNC machine, my progress on the Bridgeport had stalled. Having a very busy life made this little excuse enough to delay any effort.

Then I had a breakthrough -- a few simple realizations that were enough to get me motivated again:
1. This part really doesn't need to be aluminum, or even acrylic. It's under very little stress.
2. I can cut the part from MDF and have it done in an hour or so!
3. The design of the bracket is already done. All I need to do is make it.

Cutting the part from aluminum would take a long time: 6+ hours on the small machine available! I also could not find a suitable piece of aluminum stock to cut the part from. That was enough of a mental barrier to keep me from attempting the build. I had "builder's block!" You know, like writer's block. And so the project sat.

The idea that I could have the part in my hands in an hour changed my electronic design into reality. It was very satisfying to make chips again, even if the chips were really just MDF dust. The part bolted up perfectly, toleranced just right for a snug, but not permanent fit with the locating circle on the NEMA 42 servo motor. The bracket can also accept a NEMA 34 motor, if I need to change my mind again.

Another nice discovery -- the bracket fits! Someone asked me for the CAD models of this design a few months back, but just before I sent the models, I realized that the "star" points of my design would probably interfere with the vari-speed housing on the spindle! So I didn't send the models, thinking the design needed more adjustment. If you're following this thread and still interested in the IGES or Pro/E models, please PM me.

Of course, there is a new stopper: My helical coupling fits a 1/2" motor shaft, which is what the NEMA 34 motor used. But the NEMA 42 motor needs a 5/8" coupling. Fortunately, McMaster Carr has good prices and I was able to order one online. Hopefully it will be here on Tuesday. If you want to take a look, go to www.mcmaster.com and type in "6208K14" which is the P/N.

WooHoo! The new Z axis works!!

The motor is overkill, but it works. By default, this motor was set to 20,000 steps per inch (4000 steps/rev). Fortunately, I can change that to anything I want -- that's a nice advantage of using a resolver instead of an encoder. With so many steps/inch I decided to set the Z speed to 50 IPM, which it handled easily.

One potential flaw in the design is a bit of springyness when I force the spindle to reverse directions very fast (2 or 3 times per second). It has no problem doing a hard stop, but it seems to have more settling time than the X and Y axes. Perhaps the helical coupling that I used is not as torsionally stiff as I expected? I know the Z axis timing belt is not tensioned as well as it needs to be. Perhaps that could be another source.

In any case, I'm extremely pleased that all 3 axes are powered and working. I can start cutting steel! The first job will be to machine a replacement for that temporary MDF bracket.

Also on my list:
-Replace the Z axis limit switches (two of the 3 seem to not be working).
-Wire-in some E-Stop switches
-Mount LCD monitor on swing-arm
-Rewire control box so that computer is on a seperate circuit
(so computer can be turned on independant of drives)
-Replumb the Z axis to the Biijur lube pump
-Order a new ER32 collet holder, modify on lathe to fit my spindle nut
-Build custom electronics enclosure that mounts above the ram!

The giant electronics cabinet I have takes up far too much room. Real estate is at a premium in my garage! I really like the idea of splitting the enclosure into two sides: servo drives + computer + BOB on one side; VFD + power distribution + fuses on the other side. Both sides would be about eye-level with access through a hinging door. This configuration will also greatly reduce the cable clutter.

My quickie sketch is shown in the attached images. The object in the middle of the sketch is a crude aproximation of the Bridgeport's ram.

Any suggestions about what which components to seperate or which should be in the same compartment? Do you have successes or failures related to electrical interference you can share? I'll even take general tips about the best way to arrange components for servicability, aesthetics, cleaning, etc.

damae Looked at the pic.s of your Kerney being mooved in Your neibourghs must be understanding !!! I'm about to put power to my boss3 I had to get a transformer to drop 230v to 208 diden't see that it was a 208 machine when I got it . Did you have a tracermill in your colection? If so would it be for sale?
I'm working on gathering stuff for a lathe conversion will have servomoter's next week and I think I have the ball screw's nailed down If you have extra control part's left over from your Boss let me know I may need help Carry on Kevin

damae Just looked at the pic.s of your Boss3 when you got it and I was woundering what the box on the left side of the power encloser was maybe a frecdrive or a transformer mine dosen't have that box? let me know Thank's Kevin

damae Looked at the pic.s of your Kerney being mooved in Your neibourghs must be understanding !!!


Yes, they are! I just recently sold the K&T. Having 4 mills and a lathe in one garage made it so difficult to do anything that it just sucked the fun out of doing my CNC conversion. With the K&T gone, my lathe is usable and I even have a small area for welding with my new TIG welder! It's starting to be fun a again!


... Did you have a tracermill in your colection? If so would it be for sale?...


Yes, it's just sitting at the moment, waiting to have its retrofit finished. I intended to finish the retrofit myself, but if you're really interested, PM me and we can work something out. I wouldn't mind reclaiming even more of my garage space! =)


...If you have extra control part's left over from your Boss let me know I may need help...

I junked the control except for the BOSS computer. It's yours if you want it, but it's been sitting outside (out of the rain) for a while. I'd be glad to help if there's something I'm able to help with. Do you have a project log thread for your mill?

damae Just looked at the pic.s of your Boss3 when you got it and I was woundering what the box on the left side of the power encloser was maybe a frecdrive or a transformer mine dosen't have that box? let me know Thank's Kevin

I don't have that box anymore, but I think it was the spindle motor control.

You have far more done than I do yet. But my thinking on control cabs was to seperate AC and DC componanats for one thing. The PC if you use a micro ATX board can fit in the space of a small pizza box :-).

Bill

You have far more done than I do yet. But my thinking on control cabs was to seperate AC and DC componanats for one thing. The PC if you use a micro ATX board can fit in the space of a small pizza box :-).

Bill

I just read your project log -- your build is progressing nicely!

This cabinet will be custom, of course. So I can make it just the right size and subdivide it if needed. Your suggestion to keep the PC seperate is good. So now I'm thinking to do this:

Left side cabinet
-Servo Drives
-Incoming 230v and 115v power blocks
-Star ground point
-Main pPower switch

Right Side Cabinet (main compartment)
-Computer
-Breakout board
-Relay board

Right side cabinet (secondary compartment)
-VFD all by itself. This compartment forms a shilded chamber to keep some of the hi freq interference at bay.

Where is your 5 volt/ 12 volt power supply and your 24-72 volt power supply going to go ??

http://www.wikihow.com/Convert-a-Computer-ATX-Power-Supply-to-a-Lab-Power-Supply

You probably already have that covered.

I need to read up on Star ground as it is greek to me and I have seen it mentioned a few times.

With the micro atx PC mainboards really a case is pretty simple.

I'm not sure if my toroid will kick off enough magnetic field to disrupt an ATX power supply in the same 12 x 12 box or not ?? The wall plug power supplies from walmart are $15 each and few of them put the rating my cnc4pc breakout board wants....so I figuired an ATX supply is tons better than the wall plugs...and cheaper than the $30 for a 5 volt(didnt even find one) and a 12 volt.

Bill

Damae did you ever power up your machine as it was when you got it I thought I read that the guy demoed it for you in MDI I woundered If I was missing somthing about the start up noticed that the lub res was not full and on my BTC it will shutdoun if there is no lub and it dosen't give you an error message . Maybe the mail will bring my manuals today and I can mack some progress Kevin

Where is your 5 volt/ 12 volt power supply and your 24-72 volt power supply going to go ??

Actually, I don't need a power supply, since my Emerson servo drives take AC line voltage input. The drives have their own internal power supply. That's why they are so large.

...I need to read up on Star ground as it is greek to me and I have seen it mentioned a few times.

It might be a complex theory to understand why it works. Fortunately, it is actually very simple to do: just ground your devices at one point only. Most people use a 1/4"-20 bolt mounted to the cabinet and attach all the ground wires with ring terminals.

so I figuired an ATX supply is tons better than the wall plugs...and cheaper than the $30 for a 5 volt(didnt even find one) and a 12 volt.

I agree completely. You can also find lots of wall adapter power supplies of all voltages at your local Goodwill. A slicker solution is to buy real power supplies. I get mine from MPJA.com -- very good prices and nice power supplies.

-D

Damae did you ever power up your machine as it was...

It was working at the machine shop, but I didn't power it up after trucking it to my garage. The Biijur lube pump on my machine has no level sensor, just an AC input.

The BTC is a more recent and higher end Bridgeport, so it makes sense that it would have a level sensor.

Here's a novel idea -- use an engine stand to mount your milling machine head. I had this idea a while back, but finally got to try it out today. It was nice to get the Shizuoka head up off of the floor (on a dolly) and on wheels. When your shop is as packed as mine, you begin to value having everything on wheels.

It is also very convenient for rebuilding, cleaning, and powering-up to test out the power drawbar, speed changer, etc.

To celebrate the new working Z axis, I bought a very nice Kurt vise (model 3600V) to replace the "import" vise I sold with the K&T milling machine. I bought it from a machine shop who is replacing all conventional vises with high production vises (tombstone-style). The vise is immaculate, but didn't include the handle. Can you believe Kurt handles are $50? Just the handle! With the handle, I spent $400 for the vise. New these are $7-800.

I included a picture of the shop to show how things were rearranged with one milling machine gone. Much nicer to use when there is a little space to move around!

Hey D,

Great to see you working on your shiz. I'm using the heck out of mine but it's far from done. Tonight I ran a 2" corncob shell mill to trim some extrusions.

The next biggie for me is a uniform method of chip containment...I made a billion chips. at least 1% will wind up in the living room carpet......

mxtras said "Those covers on the head are where the quill feed mechanism would go if you had a manual machine head (from post #6)." it may be a step backwards but, i wonder if it is possible to install the manual quil feed equipment as well as run it via servo. that way if there was a simple operation that dident reguire cnc, you could just use it as a manual machine and use dual shaft servos so that you can operate x an y axis also manualy ?

Hey D,

Great to see you working on your shiz. I'm using the heck out of mine but it's far from done. Tonight I ran a 2" corncob shell mill to trim some extrusions.

The next biggie for me is a uniform method of chip containment...I made a billion chips. at least 1% will wind up in the living room carpet......

My wife is on my case if she spots any chips in the house (and there have been a few!) Not good for the dogs paws or for barefoot humans either! So I leave the shoes in the garage when I come inside. But somehow they still migrate indoors! I think it's a lesser known corollary to the "socks dissapearing from the dryer" mystery.

Barry, your Shiz is looking great! (check out www.barryfish.com if you haven't seen his Shizuoka retrofit) Your machine really came out sparkling!

....i wonder if it is possible to install the manual quil feed equipment as well as run it via servo...

There is a lot of discussion here on the 'zone about making your CNC with manual handles. Generally, I discovered two main reasons people don't usually do it:

1. If you use ballscrews, they are so efficient that the reaction forces from the cutter could backdrive whichever axes you don't have your hand on. Manual machines have low efficiency ACME screws and so there is lots of friction to prevent backdriving.
2. CNC machines (especially routers) would have the handles in very awkward locations. That wouldn't be a problem on this machine.

The Z axis is the only one that has any appeal to me as a manual axis. Since I don't have a drill press in my garage, I use the Bridgeport, or else I just drill by hand. There are times where it might be nice to use the BP in jog mode to position the part in X and Y, but do the downfeeding by hand to 'feel' my way through the drilling operation.

To do this I would have to somehow disengage the Z axis ballscrew, or else force it to backdrive the Z axis motor. I think it will be too much work for the return. (I'll just get a drill press). =)

Faced with the prospect of scratching out my missing aluminum motor mount on a very small CNC machine, my progress on the Bridgeport had stalled. Having a very busy life made this little excuse enough to delay any effort.

Then I had a breakthrough -- a few simple realizations that were enough to get me motivated again:
1. This part really doesn't need to be aluminum, or even acrylic. It's under very little stress.
2. I can cut the part from MDF and have it done in an hour or so!
3. The design of the bracket is already done. All I need to do is make it.

Cutting the part from aluminum would take a long time: 6+ hours on the small machine available! I also could not find a suitable piece of aluminum stock to cut the part from. That was enough of a mental barrier to keep me from attempting the build. I had "builder's block!" You know, like writer's block. And so the project sat.

The idea that I could have the part in my hands in an hour changed my electronic design into reality. It was very satisfying to make chips again, even if the chips were really just MDF dust. The part bolted up perfectly, toleranced just right for a snug, but not permanent fit with the locating circle on the NEMA 42 servo motor. The bracket can also accept a NEMA 34 motor, if I need to change my mind again.

Another nice discovery -- the bracket fits! Someone asked me for the CAD models of this design a few months back, but just before I sent the models, I realized that the "star" points of my design would probably interfere with the vari-speed housing on the spindle! So I didn't send the models, thinking the design needed more adjustment. If you're following this thread and still interested in the IGES or Pro/E models, please PM me.

Of course, there is a new stopper: My helical coupling fits a 1/2" motor shaft, which is what the NEMA 34 motor used. But the NEMA 42 motor needs a 5/8" coupling. Fortunately, McMaster Carr has good prices and I was able to order one online. Hopefully it will be here on Tuesday. If you want to take a look, go to www.mcmaster.com and type in "6208K14" which is the P/N.





I designed a similar plate for my diy cnc router a while back but then decided instead of the star I cut it as a circle.

PS. I think your garage is fulllllll. :D :D

Jason

Yup. First thing you tend to want to do as you transition from a manual mill to CNC is preserve old habits and keep the handles. "the feel !"

There is no reason whatsoever to have handles on a mill. I'm not really a machinist. I don't know much about it, other than the results that I wish to achieve. When the manual mill starts chattering, you back off. When you start a job and are unsure on your CNC, you just go slow. You can always change the feed rate. Since it's more consistant than you will ever be when you crank manually, you can observe the results and change accordingly.

For irregular milling jobs that have a "I really just want to throw this in the vice on the manual mill feel", I just set a 0,0,0 reletive home location and jog at a rate that I think will work. As I get close I just slow the jog or use incremental jogs and record the endpoints. Then I can just enter the Gcode manually at a few thow closer and repeat the path to get a sweet finish cut.

Sometimes I use the MDI line to go to my endpoints. MDI has helped me get better with Gcode as you tend to be careful before you hit enter.....

I've also drilled quite a few holes in almost every type of material using a hand drill and drill press. I've never felt as confortable as when I have a part clamped on the CNC mill and just drill at a good feed rate. It's sweet and produces a much better result at exactly the location that you want. Even better still is that you can just go back to that location and tap the hole too.


Barry

Can you give me some details on the Emerson drives you used on this retro? Why did you choose them over the Gecko 320 step to servo drive?

Thanks,

Doug Danielson

Can you give me some details on the Emerson drives you used on this retro? Why did you choose them over the Gecko 320 step to servo drive?
Thanks,
Doug Danielson
He's using brushless motors, and thus the Geckos will not work.

The winter is my busy season at work and it's hard to scratch out enough time to make progress on my machine. But it seems there is still interest even without progress! Thank you guys for sticking with me =)

Jason: Nice motor mount! Your design yields a much better bang-for-the-buck! And yes, you're right -- my garage is .. uh.. loaded! I'll be working on that clutter problem as the winter yields to dry/warm weather and I can open the garage up to reorganize.

Doug: Unterhaus is right, my motors are 3 phase AC brushless, also made by Emerson. In fact, these motors really are not designed to run with any other controller than Emerson. They use resolvers instead of encoders, making them pretty picky about what controller drives them.

I like overkill! Really, I used the Emerson motors/controllers just because I found a good deal and was fortunate enough to buy working units. If I had to do it over again, I would likely go with Rutex or Gecko drives.

Barry: You and I are thinking along the same lines. I put my mill to limited use cutting while in jog mode. But like you, I find that DNC is the just about the best way to do really controlled cuts. As I get better at hand-coding, DNC seems like the best way to do "manual" machining on a CNC. I saw your pictures of CNC tapping on your Shiz -- very nice! That is a long way off for me, but certainly would be nice to have!

I just bought a AN-S Shiz with a dead Bandit control and am planning the retrofit. I see you have one, so what are your plans for its controls?

Barry and I live about 20 miles apart, so I drove up and looked at his Shiz, which gave me the confidence to go ahead and bid to win the one on ebay.

Thanks,

Doug Danielson

Hey Doug, welcome to the retro club!

The AN-S is a really solid machine. They are well built and retrofit friendly. Technically, the Bandit controller was a retrofit. So I'm doing a retro on a retro!

So the rough plan looks like this:

Mach3 for front end
GREX for motion control/breakout
Reuse original servo motors + new encoders
Gecko (or Rutex) for motor amplifier
Build my own power supply (I have lots of surplus toroids)
Rebuild motor mounts
Build new control housing

Since the Shizuoka is the last machine on my retrofit list, presumably I'll be making less mistakes by then. I'll have to invent new kinds of mistakes! For instance, I've never botched a toolchanger retrofit before, and I keenly anticipate doing so! The toolchanger is pretty messed up on my machine, so It may never work properly again. For sure it will require reinventing and redesigining some of the basic mechanical components, like the tool grabbing arm.

Barry is just finishing his first-class retrofit, so I'm sure you will be able to learn a lot from looking at his project by seeing it in person. I wish I had pressure-washed my mill before I got it in the garage. Barry's mill is squeaky-clean! I'm still scraping grime on mine. =)

After destroying my final good 1/2" endmill, I realized how much I needed a cooling system.

And so I proceeded to hiijack my wife's watering can and tried pouring the coolant into the path of the cutter manually. Not only was my arm tired, but it was an extremely messy process trying to fill up the can and resume pouring before the cutter made the next pass!

Hearing of my troubles, my neighbor had some pity on me and loaned me his tiny water fountain pump. It managed to get fluid about 18" up the pipe, but could not muster enough head to get it up to the table! That's when I finally gave in and ordered a 10 gallon system from Enco for about $130. And boy am I glad I did!

The metal tank is nothing special -- just welded sheetmetal. But the pump is quiet and powerful. In fact, it can pump about twice as fast as my table drain can return the fluid back down to the coolant tank! Fluid was again splashing everywhere because of the powerful stream. Fortunately, I realized I can control the flow by partially closing the supplied ball valve.

then it was on to rigging a better spray shield. By better, I mean better than a bunch of cardboard clipped to the table, which is what I had for my earlier coolant experiments. Haha! First, I have a polycarbonate vise-mounted shield made by Kurt. Next, I started to make use of bits of aluminum I bought at the scrapyard "because someday I'll need it." Tin snips made short work of the thinnest pieces and I placed them in between the Kurt shield and my rear splashguard. The rear splashgaurd was originally an aluminum keyboard shelf, but it fits perfectly on my table, almost like it belongs there!

I already made some cuts with coolant and it really does make a huge difference! I'm pleased as punch... or is that blue kool-mist?

Hey, some pictures! (more pictures)

This time showing a fixture I'm cutting into some soft jaws that will be mounted in the Kurt vise. The process worked beautifully, cutting .050" deep at 40 IPM and 3000 RPM, probably still very conservative. The finish was great and everything went as I hoped. Oh, except for being out of tolerance by 0.020"!!!!

Yeah, I found a 1/2" EM in a pile of old tooling and thought "great, I don't have to wait for my new cutters to arrive," but I didn't realize it had a "history." Some time in this cutter's past, it had been resharpened, and in the process made into a 0.490" EM instead of a 1/2" EM as marked on the shank. So now I'm dead in the water until my new cutters arrive.

Oh well -- I'm still pleased as Kool-Mist that the coolant works so well!

Hey Damae,

I love seeing you use coolant. I need it, but have been afraid of the mess management. You are forcing me to forge ahead. What coolant are you using????

Thanks for the praise on my retro but it is really far from being done. I want to try to get the front panel in place soon so that there is a real Estop button (instead of the keyboard or mouse estops) I also need to mount the buttons for my drawbar as the switch is dangling by the wires...

Washing Machine: I was forced to use the pressure washer due to the mass of clay-grease like crud on the machine. Even after PW, it took weeks of scraping, washing, dis-assembling, scotch-brighting and lube spraying to get it clean enough to touch with my "day job" clothes on. Attached image are brackets that still need to go on the machine - 1/8" crud missed by PW.

As far as the Estop goes, I think that I will add a contactor between the power supply and the motors so that the DC is instantly shut off to stop the motors without waiting for the big cap to discharge. On Kens big machine Fanuc has a contactor for each motor. When engaged everything is normal; when disengaged, the contactor shorts the motor out. This has the effect of stopping it instantly and acting as a power-off-parking-brake.

One other question? do you use a keyless chuck? I have a new (gifted to me) Albrecht which I used for some various CNC drilling (3/8 & #29) on some of my aluminum extrusions. Maybe I just don't know how to get it tight, but it has slipped more than once. Some guys swear by them - At this point I swear at it. If I don't get help, it's going to get religated to the basement drillpress.....

best regards,

B

Amae Look's like your on the right track with the coolant take a look at my encloser on the BTC clubhouse the base is the origonal BPT and the rest is almost done. might be to big for your space your part look's like a soft jaw for a kurt vice ? Can you overcome the size with cuttercomp or rewright the tool path +.005" offset? I have yet to master CC even though my machine is capable but offten just regenerate the tool path when faced with the wrong size tool Keep up the good work Kevin

I buy "resharpned" carbide cutters by the dozen from a very good grind shop in Tucson. Cost is $4-$5 each, and he does an outstanding job on the resharpen. I mark each cutter with the actual measurment, then put it in the the tool log in my Vector CAD/ CAM program ( I also number them) and Desk CNC. The measurements are comped in the tool path..This is ok where only one person is using the equipment, but in a High Tolerance shop it may be dangerous..You know, make 4000 widgets( sorry Eric )and be off 0.010 could be more expensive than the money saved.

I actually took a day and went to some CNC shops and bought their so called "scraped" carbide cutters..I came home with 140 good canidates for resharpen for less than $40 bucks and some diesel fuel..I found a lot of good end mills that had been tossed for no reason, the rest I had sharpned.

Found a bunch of little plastic containers that we used for each carbide end mill to keep them apart and organised. I figured my cost per carbide end-mill
( most are 1/2", some 3/4", and very few 1//4"and 3/8") is about $7.00 each,
a lot less than even Enco..

Adobe (old as dirt)

One other question? do you use a keyless chuck? I have a new (gifted to me) Albrecht which I used for some various CNC drilling (3/8 & #29) on some of my aluminum extrusions. Maybe I just don't know how to get it tight, but it has slipped more than once. Some guys swear by them - At this point I swear at it. If I don't get help, it's going to get religated to the basement drillpress.....

best regards,

B
I think for heavy cuts you are better off with a keyed chuck. I don't think they really work at 3/8-1/2". I've used them for edge finding and center drilling, and some small drills.

...I love seeing you use coolant. I need it, but have been afraid of the mess management. You are forcing me to forge ahead. What coolant are you using????


Barry, glad to 'twist your arm' into using coolant! =) I use Kool-Mist, mixed very rich, about 5:1 because I absolutely want to avoid rust problems. No particular reason for picking this brand, except that my local supplier (Tool Supply Inc.) has this on hand.


Thanks for the praise on my retro but it is really far from being done. I want to try to get the front panel in place soon so that there is a real Estop button (instead of the keyboard or mouse estops) I also need to mount the buttons for my drawbar as the switch is dangling by the wires...


Same here! I want to mount at least one E-Stop close to the front of the machine. It's especially troublesome to have to open the control box enclosure just to turn the spindle on or off!


Washing Machine: I was forced to use the pressure washer due to the mass of clay-grease like crud on the machine. Even after PW, it took weeks of scraping, washing, dis-assembling, scotch-brighting and lube spraying to get it clean enough to touch with my "day job" clothes on...

I suppose there's no true shortcut to cleaning up a decade or more of grime! Except to hire a high school student to do it for you! Haha!


One other question? do you use a keyless chuck? ...Maybe I just don't know how to get it tight, but it has slipped more than once. ...

Well, I doubt you're doing something wrong -- keyless chucks should reach full tightness by hand. I was just bidding on a drill chuck for my machine, and was wondering the same thing. Based on what you say, I'm going to get a keyed chuck instead of keyless, just to be safe.

... take a look at my encloser on the BTC clubhouse the base is the origonal BPT and the rest is almost done....


Kevin, that's a really nice setup you have there! I do need to figure out something more permanent, but I was thinking to keep it contained inside the dimensions of the table.


...look's like a soft jaw for a kurt vice ? Can you overcome the size with cuttercomp or rewright the tool path +.005" offset? ...

Yes, it is an aluminum soft jaw I was cutting on. You are also right about adjusting toolpaths and cutter diameters in software... so I guess I don't really have an excuse to hide behind, do I? =) It's a bit of a pain to regen the toolpaths, because I am still very clumsy with BobCAM and transfering the file is a little awkward. I have to put it on a USB stick, carry it downstairs, open the control cabinet, unplug the USB keyboard and insert the USB memory stick, copy the file (using mouse only) and then swap the keyboard back in.

I sorely need a USB hub and a panel-mount USB port!

I buy "resharpned" carbide cutters by the dozen from a very good grind shop in Tucson. Cost is $4-$5 each, and he does an outstanding job on the resharpen...


Not a bad idea! I already have my own pile of wasted tooling. Perhaps they can be shortened and reground.


I actually took a day and went to some CNC shops and bought their so called "scraped" carbide cutters..I came home with 140 good canidates for resharpen for less than $40 bucks and some diesel fuel..I found a lot of good end mills that had been tossed for no reason, the rest I had sharpned.... I figured my cost per carbide end-mill ... is about $7.00 each, a lot less than even Enco..


Thanks for the hot tip! Do you trust your calipers to produce an accurate measured diameter, or do you make a hole with the cutter and then check the hole with gage pins to account for uneven or off-center grinding? Or is that not a problem at all?

D,

From what I understand, you want to mix the coolant with the proper concentration. They even sell refractometers to ensure the concentartion is correct.

from http://www.coolantmaintenance.com/
Too low a concentration can dull tools prematurely, or even break them during the first cut. Too high a concentration not only causes higher usage rates, but can also lead to health and safety issues.

B

D,
From what I understand, you want to mix the coolant with the proper concentration...

Hey, nice new avatar, Barry! Shizuoka Red!

You bring up a good point about health issues with high concentrations. I just really, really hate rust. I guess that comes from growing up in Hawaii, where every car over 5 years old has rust! In fact, I never did own a car there that didn't have visible body rust; one even had rust so bad you could stand in the hatch area with your feet thru the car, like Fred Flintstone!

Anyway, who likes rust? Of course, I am only assuming higher concentrations of coolant mean less corrosion.

You're right, I really do need to see what concentration is appropriate. Kool Mist 77 is 100% synthetic and intended to be mixed pretty thin -- 32:1! This particular brand is meant to be used as either mist or flood coolant. I wonder if I can get away with higher concentrations when using it in a flood-only application.

I also bought a large box of latex gloves to use around the coolant.

Re: reground tooling. I cut a slot in some scrap alum, then measure using my guage block set..quick and easy for tolerances of .001 to.002, if I have to mill to tenths, use a new , carbide endmill, but have gotten in the habit of checking those the same way.I have some new, never used 1/2 " end mills that are 3-4 years old..due to using the regrinds.At least there might be something new when my wife auctions everything..

Adobe (old as dirt)

D,

Have you had a rust problem due to coolant?



My machine is in the garage and the physics are bad.

The temperature in the garage can get into the 40s fairly easily. Then in the day the outside temperature goes way up. If it rains and someone opens the garage, the machine sweats (a lot)

Every surface of the machine has a light coat of LPS II which seems to offer enough protection. (LPS is by far the best spray lube I've found, and the II is a good general viscosity) (It's also a good cleaner of thick stuck on greasy-grime)

Sometimes I'll run a heater on the machine just to cut down on the condensation. As long as it's a couple of degF hotter the moisture is driven elsewhere.

B

D,
The temperature in the garage can get into the 40s fairly easily. Then in the day the outside temperature goes way up. If it rains and someone opens the garage, the machine sweats (a lot)

Every surface of the machine has a light coat of LPS II which seems to offer enough protection. (LPS is by far the best spray lube I've found, and the II is a good general viscosity) (It's also a good cleaner of thick stuck on greasy-grime)


This is my first experience with coolant, so I've not had problems with it causing rust... yet! =)

Yes, I have the same extremes in my garage and I combat it a few ways:

-I don't open the garage when it's raining or humid outside. (except to take the trash out)
-30 pounds of desiccant packages distributed around the shop -- including one packet in each tool drawer. This helps keep the air dry and remove whatever moisture sneaks in.
-Dehumidifier. Ran automatically and worked great, but recently stopped working. It acts like the refrigerant leaked out.

I like heat lamps for the same reason you heat your mills -- just to keep them slightly warmer than the air, without circulating more air across them while they're still warming up.

How about this for a PIC project: an Automatic Mill Heater. Electrically heating your mill would be expensive if you just left the heat on all the time without regard for the temperature difference. But we could monitor the ambient temperature, the air humidity, and mill temperature, and apply simple rules:

If the air humidity is anything other than bone-dry, then:
Check the temperature delta.
The mill should be more than 3 degrees warmer than the air
If it is not, then turn heater on
If it is, then turn heater off
Repeat

We could build-in an audible humidity alarm (beeps every 5 minutes if conditions are likely to cause the mill to sweat).

We could also record the peak/lowest humidity in the past 24 hours and display on a LCD.

I have the ICD2 from Microchip and a dev board based on the 16F977. Work is consuming all my time right now, but when I get back to regular hours, I'll give this a shot. I also have two PIC16F84A MCUs that might be adequate.

I got the rust and sweat part, but missed the beers. Are you going to HK/SZ?

I got the rust and sweat part, but missed the beers. Are you going to HK/SZ?

I was looking for a post title with a funny analog to blood, sweat, tears and it rhymed. You're right, I forgot to tie-in the beers.

I have a narrow window. I'm trying to kick-off tooling before Chinese New Year and then get over there to work out the bugs with the toolmakers in person. So it's looking like the first week of February right now. You still going?

Back when I worked in the electrical business..

The electrical cabnets had heaters to drive out the moisture. They had simple thermostats and that worked fairly well.

Back when I built solar water heater panels...

I used 2 simple thermistors and an op-amp. When the panel got hotter than the tank, the pump came on. You just tweaked the bias to keep it off unless you had some differential. There was a little positive feedback which made the unit switch with a couple of degrees difference (so that the pump cycled on and off.)

I might be tempted to just rig up one of those type circuits. good, fast cheap, reliable.

I've seen all of the heater types on MCMASTER.com page 477 installed in cabinets. If you are serious about installing heaters, I'll call my bro. He had several laying around the last time I was there (Florida) Maybe freeer (rhymes with beer - keeping with the theme) than McMaster.

Let me know.

B

Jan 22nd to 27th with possible extension. No jumping banana.

I've been working on some control panel mockups using inkscape, which, by the way, is a wonderful free (opensource) vector editor, kind of like Adobe Illustrator. It's very easy to use, very intuitive.

Anyway, Here is what I was thinking for controls. I already have an industrial monitor enclosure, so I started there, placing the e-stop and all "powering-up" and enable functions. These switches would be tied to relays, perhaps indirectly through Mach. The small box above the monitor is a detatchable panel that controls my Mitsubishi VFD and displays the spindle speed.

The second panel I intend to mount to the center of the machine, just below the table. It actually will form a more cosmetic cover for the Y-axis pulley cover.

I'm looking for feedback. What controls did I miss? What won't I use? What indicators should I add? I was trying to keep it simple, without losing any important funtions.

Hey D,

Man thats a nice looking panel. Got any more?

I might be tempted to put the buttons that I use a lot or that need to be handy in the holes that you have available.

Feed Hold
Drawbar open/close
Spindle Power
Axis Enable

BW(HK)

Hey D,

Man thats a nice looking panel. Got any more?

I might be tempted to put the buttons that I use a lot or that need to be handy in the holes that you have available.

Feed Hold
Drawbar open/close
Spindle Power
Axis Enable

BW(HK)

Hey Barry, how's your Hong Kong trip going? My project is delayed and so I likely won't be back to HK until April, but when I do go, it will be for 3 weeks!

That is my only remaining control panel. I had reserved a few more of them at the junkyard where I bought it, but I never picked them up. That was last summer, so I think they're gone by now. =(

Good idea about the Feed Hold button! I would have kicked myself if I left it out!

Damae,
GREAT thread!!! I don't know how I missed it!!!

So I guess you had to make the Z axis pulley? Know where I can get one & a belt for my BOSS 5? Know where I might find a Series I spindle bearing set?

Thanks!
-B

PS...now I have to go back & re-read this entire post and try not to get lost in all of the links you posted! :)

Damae,
GREAT thread!!! I don't know how I missed it!!!


Thanks for the compliment! Just giving back.. considering how much I've learned from the build logs of other members!


...Know where I can get one & a belt for my BOSS 5? Know where I might find a Series I spindle bearing set?


I made a plan to make my own pulley, but in the end, bought one from Misumi. If you prefer to make your own, a neat trick is to download the CAD model from Misumi's website and use that model to machine your own pulley. That's what I used to make my X axis pulley -- although I used a rapid prototyping machine for that pulley, not CNC.

https://fa.misumiusa.com/gwos/catalog/catalog_list_pc050.aspx?CATALOG_ID=0001&CATEGORY_ID=023

Eventually, I will make a new X-axis pulley out of aluminum, the way I described in an earlier post.

McMaster-Carr has very good prices on H-pitch belts. I don't remember how many teeth you'll need on the Z axis, but it is a H100 series (H pitch, 1" wide).

http://www.mcmaster.com/

As for spindle bearings, I have seen good deals for a spingle bearing set on ebay, but have no idea if you can trust the quality. McMaster will also carry the appropriate bearings, but I am not sure if their bearing prices are competitive.

Machinetek, a member here on the 'zone is our local Bridgeport expert and he has been known to help out when people post a specific question on in the Bridgeport sub-forum. You might try that if you have more particular questions. For instance, he probably knows how many teeth on that belt and which bearing numbers to use.

Are you doing a retrofit on your mill? If so, post a link, I would love to check it out!

Thanks man...you've been more helpful than you know!!!

Question: Are the BOSS pulleys metric? I didn't see an SAE/inch reference on there.

My retrofit has taken more turns than Suzuka Raceway :drowning: First I ran the machine under it's own power & just moving the machine around, it kept blowing transistors...So I bought some DC motors from surplus center to do a servo conversion and then realized that there was no way it was going to fit on the Y (unless it was going to be sticking straight out...which is not what I wanted)...So I figured, why not use Nema34 motors, and bought some N34 Tormach 1200Oz motors and G202s....Knowing full well I needed shaft adapters and N42 to N34 mounting plates. I cut the plates out no problem on my CNC plasma, and then had some adapters turned on a lathe & drilled & tapped for grub screws...Worked OK for a while, but I really wasn't keen on the adapters...So since then, I've said screw it, and put the original N42 motors back on the machine & will be running 1/2 winding to keep amps down on the Geckos...

The electronics box is gutted...I still have to take it all apart and clean out years of goo & putty...One good thing is that I only see AL chips in the remotest of places...so hopefully she wasn't ridden to hard.

Here's good ole Bridget in the Ebay spotlight before I bought her, a Rhino render of the shaft adapter and the N34 Tormach's mounted on the machine:

Here are the ways...and one reason I bought the machine :)

damae I'v seen some new fadal jog pendent's on ebay thought this would make quick work of some of this maybe a lube level light ? The jog pendent would be handy during set up and touch off look's Good Kevin

My wife is on my case if she spots any chips in the house (and there have been a few!) Not good for the dogs paws or for barefoot humans either! So I leave the shoes in the garage when I come inside. But somehow they still migrate indoors! I think it's a lesser known corollary to the "socks dissapearing from the dryer" mystery.

Barry, your Shiz is looking great! (check out www.barryfish.com (http://www.barryfish.com) if you haven't seen his Shizuoka retrofit) Your machine really came out sparkling!



There is a lot of discussion here on the 'zone about making your CNC with manual handles. Generally, I discovered two main reasons people don't usually do it:

1. If you use ballscrews, they are so efficient that the reaction forces from the cutter could backdrive whichever axes you don't have your hand on. Manual machines have low efficiency ACME screws and so there is lots of friction to prevent backdriving.
2. CNC machines (especially routers) would have the handles in very awkward locations. That wouldn't be a problem on this machine.

The Z axis is the only one that has any appeal to me as a manual axis. Since I don't have a drill press in my garage, I use the Bridgeport, or else I just drill by hand. There are times where it might be nice to use the BP in jog mode to position the part in X and Y, but do the downfeeding by hand to 'feel' my way through the drilling operation.

To do this I would have to somehow disengage the Z axis ballscrew, or else force it to backdrive the Z axis motor. I think it will be too much work for the return. (I'll just get a drill press). =)

I was just wondering if anyone had designed a hybrid manual/cnc using electronic control since the servos/steppers are already in place. Seems like some operator feedback would be needed (like a force-feedback joystick).

Bnoji,

I'd save the feedback for the giant robot suit. Even when you think that you can "feel" some magic feedback force, you can't do much better than with constant feed rates.

I recently drilled a bunch of 1/8" pilot holes followed by 3/8 drill through 1" plate steel and the results were fantastic.

I think that when you hand drill (machine, cut, etc) you keep constant FORCE going toward the subject material and when you use CNC you keep constant VELOCITY applied. With the constant velocity, you allow time for the chips to clear.

Barry

Another nice discovery -- the bracket fits! Someone asked me for the CAD models of this design a few months back, but just before I sent the models, I realized that the "star" points of my design would probably interfere with the vari-speed housing on the spindle! So I didn't send the models, thinking the design needed more adjustment. If you're following this thread and still interested in the IGES or Pro/E models, please PM me.



I was the one that asked for the CAD models. I have been off line for a long time due to being a new father and starting a new company at the same time. I just sent you a PM but your over the limit so it didn't go thru.