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victorbl
01-04-2005, 12:36 AM
I've been trolling the forums for the past few weeks an have been really inspired by some of the machines that I have seen posted. I decided it was time to take the plunge and build one for myself as I can think of quite a few woodworking and electronics projects where the precision would come in handy. So, I spend about two weeks collecting/ordering parts, as well as drafting up a plan for the machine itself.

The hardest part for me was making design decisions for the machine based on the different feedback it has recieved in the forums. Things like fixed versus moving bridge, skate bearings versus bushings, etc. So, with this being my first machine, I decided to take a conservative approach, and borrow alot of the decisions from machines posted to the forum that were iterated on. Most of my design was inspired by jgro's second machine.

The specs 'thus far'
* Approximatly 17 x 16 x 5 cutting area
* Fixed bridge, moving X axis table design
* The Y and Z axis are supported with 3/4" drill rod riding on oilite bushings
* The X axis will be supported on 1" drill rod riding on oilite bushings
* All three motors are 116oz/in Pac Sci
* Driven by a Xylotex board with a 24v 6amp power supply
* Using 1/2-10 Precision ACME lead screws and home made Delrin nuts

I began construction three days ago, and have mostly completed the Z and Y axis. I still need to get the motors and screws mounted, then move to the X axis and table. Finally, wrap it up with some paint.

I wired up the motors/powersupply/driver board last night and had the motors turning with Mach2 (I know the superstition, but I'm too invested now to quit). I'm really looking forward to getting them mounted on the Y and Z to see it come to life. My first designated project for the machine (once I get the hang of it) will be to create a nice 1/2" baltic birch case for the electronics.

So enough talk and on to some pictures. I'll try and stay active on posting my progress...and plenty of pictures. I can appreciate how much the pictures helped me when I was designing.

(if your curious why the MDF looks two different colors, I shellac'ed some of the pieces to prevent any premature moisture damage before I got around to painting it)

BobLWeiss
01-04-2005, 08:31 AM
Looks good so far..nice job.

Can't wait to see more pictures! What software are you going to use with it? Are you using a dremel for the spindle?

Bob

jgro
01-04-2005, 08:53 AM
Looking good :) Are your bushings glued in? Mine weren't, so I filed a notch into the flange with a round file and drilled a hole through the mdf so that I could put a bolt through to hold the bushing from pulling out.

jgro

victorbl
01-04-2005, 02:40 PM
BobLWeiss: My 'real job' is in software development and graphics, so I have access to some modeling packages that we no longer use at the office. I'll probably use 3D Studio MAX or CorelDraw for my modeling, and I will most likely pay to register Mach2 as my driver. Any recommendations on a DXF->GCode converter?

For the cutter, I already have a dewalt heavy duty cut out tool, and a dewalt 2.25 HP router...as well as a dremel. I would prefer an off the shelf solution versus building a spindle if possible. I think my main goals will be some basic pen plotting, creating some 3D shapes in MDF, and hopefully a few circuit boards.

jgro: Thanks for the feedback, I should really be thanking you :). I saw your use of the bolts to hold the bushings in and I actually predrilled most of the MDF around the bushings to accept a bolt to hold the bushing in place. I did drill the holes for the bushings just one size too small, and after shellacing the holes, the bushings are a tight friction fit. I think my plan in the end is to pull them all out before I paint the whole thing, then go ahead and secure them with bolts as you did as an extra precaution.

I did have a question...why did you choose to go with 'skate bearings' on your X axis? Was it so you could support the 1" drill rod from the bottom? I'm currently planning on using the 1" oilite bushings on my X just because they don't seem like they will carry much weight, but I could be wrong.

jgro
01-04-2005, 02:52 PM
I spent about a month trying to get bushings to work on the x axis. I just couldn't get it to work without binding. I finally gave up and went the skate bearing route. Maybe you will have better success than I did.

jgro

MrBean
01-04-2005, 03:22 PM
Any recommendations on a DXF->GCode converter?

If you're planning on using Mach2, it has a built in DXF->GCode convertor.

Regards Terry.....

victorbl
01-04-2005, 05:55 PM
I'll have to try an import a simple DXF into Mach2 to see if I can understand how to specify things like cut depth, etc.

I'm curious if anyone has any recommendations of a good set of basic cutters that I should order/buy so I will have them when I wrap up the machine. I've heard words like 'end mills' and 'ball mills' thrown around. Can someone provide maybe a starter list of some good bits to get, and where to order/buy them from?

Projects I have in mind:
* Shaping 3D pieces with plastic or MDF - like clock gears
* Cutting 1/2" and 3/4" plywood - such as for a case for my electronics
* Circuit boards

Thanks!

asher
01-04-2005, 11:25 PM
JGRO Could you please tell me where you got your wire track and how much?? Thanks in advance Jason

jgro
01-05-2005, 09:02 AM
We got it at work from Igus. They sent us a sample pack when we were working on a project and the chain guides were a part of it.

jgro

victorbl
01-09-2005, 11:33 PM
Things seem to be progressing well. I spent some time this weekend building the X axis table and a frame to hold it all. I also started to mount the motors/acme screws/drill rod.

I'm noticing that even though I spend a considerable amount of time setting up all of the drills for the bushings and support blocks, it is going to take a considerable amount of tweaking to get everything to slide around without binding.

I ordered three <a href="http://www.surpluscenter.com/item.asp?UID=2005010922222371&item=1-201-08-4&catname=powerTrans">Flange Bearings</a> last week to use at the opposite side of the motor for each axis.

jgro: I'm noticing when the bushings and drill rod line up perfectly after a ton of tweaking, they slide great. But, one degree off, and your fighting it. Do you lubricate your drill rod with anything to further assist the bushings?

ger21
01-10-2005, 08:09 AM
Read post #5. He got rid of them.

jgro
01-10-2005, 09:17 AM
I got rid of them on my long axis. My two short axis still have bushings. I put some silicone based lubricant on the shafts after every couple of uses. It keeps them slippery :)

jgro

victorbl
01-11-2005, 01:21 AM
Well, after thinking it over, and some great advice from jgro, I think I've corrected my drillrod/bushing binding problems. Reguardless of the fact that I had spent time squaring my drill press, building a jig to align the bushing holes, and assembling the axis's with the drill rod in place, there was still some light binding of the oilite bushings with the drill rod. I had drilled my bushing holes such that they were a snug fit, but as I see now, that was a mistake.

Basically, no matter how square and lined up I had my bushing holes, it's still MDF, so there is always going to be just enough play (even if it's a fraction of a millimeter) to cause some unneeded binding. Granted, it wasn't locked, but it did require a little pressure to slide some of the axis's. So, to fix this, I took jgro's advice and bored out each of the bushing holes just enough such that bushing just slid into the MDF versus needing pressure to get them into the MDF (think exact fit, no longer a friction fit). This freed them up just enough to make the drill rod slide smooth as silk. Even adjusting the blocks wouldn't clear all the binding if your bind is just between two bushings.

If I were to do it all over again, I might have considered using UHMW flanged bushings from mcmaster. They are about $6 a piece versus $2 for the oilite bushings....but I think they might have been a little more forgiving. And my sanity is worth the extra $4 per bushing :)

victorbl
01-12-2005, 04:01 AM
It's finally starting to resemble a real machine. Still alot left to do, but I'm starting to believe that this thing might actually work when I'm done with it!

jgro
01-12-2005, 11:21 AM
Looking good!

BobLWeiss
01-12-2005, 01:52 PM
Where did you get your threaded rods from? I love the design and it looks like it gonna work out nice for you.

victorbl
01-12-2005, 02:14 PM
I purchased the Precision ACME threaded rod from MSC Industrial Supply

<a href="http://www1.mscdirect.com/CGI/NNSRIT?PMAKA=01206036">link to Precision ACME lead screw</a>

Overall, I have been really satisfied with the design, though, if I were to do it again, or give advice to those building a similar machine to this one, go with 1" UHMW flange bushings on the X axis instead of the cheaper bronze bushings. My X axis is now setup so that there is no detectable binding between the bushings and the drill rod, however, the force required to overcome friction and start the X axis in motion is just high enough to make me a bit concerned. I think this is contributed to the fact that the X axis tends to be a bit heavy, and i'm dealing with a metal bushing on metal drill rod.

I'm going to try and use my existing setup this weekend to make some sample plots/cuts to see if everything is acceptable, I'll keep you posted.

BobLWeiss
01-12-2005, 02:32 PM
These flanges you are talking about using instead, did you get them at the same place as the rod?

I am thinking of making another machine using JGRO's plans...nice design.

victorbl
01-12-2005, 02:45 PM
For reference, here are the oilite flanged bushings that I purchased

From www.mcmaster.com
* SAE 841 Bronze Flanged Bearing for 1" Shaft - 6338K437
* SAE 841 Bronze Flanged Bearing for 3/4" Shaft - 6338K433

However, later, I may "upgrade" my current bushings to UHMW which can be found here:

From www.mcmaster.com
* UHMW Flanged Bearing for 1" Shaft - 57785K28
* UHMW Flanged Bearing for 3/4" Shaft - 57785K27

BobLWeiss
01-12-2005, 03:38 PM
Thanks for the links!! One last question, how did you make the nuts for the threaded rods? I have been looking on McMasters for nuts and they are expensive and come in 2 peices each. THey are not antibacklash type either, just plain nuts with mounting flanges...like $50 each. I would love to make my own since you need 3 of them.

Thanks again!

victorbl
01-12-2005, 03:51 PM
The idea for the anti-backlash nuts were taken from different posts around this forum. Here is were my take aways

* Purchase a block of Delrin. I bought a Rectangular bar 1" thick, 2-1/2" wide, 12inches long from mcmaster - 8662K64
* I cut out three blocks, 2-1/2" x 2-1/2" if I remember correctly
* I cut off a 5 inch piece of one of my precision ACME threaded rods that I knew I wouldn't need
* I chucked it up on my drill press, and using a file, I filed down the bottom 1-1/2" much like a retail tap is shaped (just look at any taps you have, or on pictures from a website). If you don't have a drill press, probably a drill in a vice would be fine for this.
* I took my dremel tool, and carved out 4 valleys going down the taper. This gives the removed Delrin a place to go, and provides a shaper surface for cutting the threads. Look at a regular tap, you'll see what I mean.
* Drill a straight hole down the center of the Delrin that is only the diameter of the ACME rod minus the threads
* Using vicegrips and some decent pressure, tap the Delrin with your home made tap.

This will get you a mountable AMCE nut that has minimal backlash. If you would like to further ensure that you won't have any backlash, you can use a bandsaw or hacksaw to crosssection about 70% of your Delrin nut, and then use a bolt to put additional tension on the ACME rod going through it by slightly spreading the halved Delrin. Do a search on the forums and you should be able to find great examples of this.

If I think about it, I'll snap some pictures tonight to help illustrate this.

mvaughn
01-12-2005, 04:16 PM
Victor,

how easily does the acme rod turn in the anti-backlash nuts?

I'm working on mounting my lead nuts and screws on my machine and I'm concerned that the steppers will not be able to turn the 1/4 10tpi ACME thread through the UHMW anti-backlash nut.

In fact I was so concerned that I had a backup plan to us 1/4 20 allthread instead. I bought a 1/4 20 tap from Sears and threaded a test chunk of UHMW and found that it was rather sticky, even with silicon lubricant.

victorbl
01-12-2005, 06:05 PM
Hey mvaughn,

I can't speak for nuts made from UHMW, but I found that the ones tapped in Delrin are very easy to turn once they have been broken in just a bit. I have read that Delrin is self lubricating, which may be an additional reason it is so easy.

If your using UHMW, try this. Tap a scrap piece if one is available just like the others, and then place the UHMW piece in your vice. Hand thread your screw through the UHMW. There should be a slight amount of pressure required which just validates that you have a tightly tapped nut, but if it's almost to the point where you need plyers to comfortably do it, it is probably too much for 116oz motors (in my situation).

Take your power drill, and chuck up your threaded rod, and carefully hand thread the first few turns back into your UHMW (this prevents the drill from cross threading your UHMW). Once it's in, run the drill at a higher speed to screw the rod through your tapped hole. I usually ran the rod once all the way in, and once all the way out (my rods were 36"). This was enough wear to break them in such that there was still no noticable backlash, but loosened them so I can simply hand turn them without much force.

Hope this works for you.

Hobbiest
01-12-2005, 11:56 PM
UHMW is self lubricating too, just not as good as Delrin. Try this...drill the hole in your UHMW, then freeze it. Take the block out of the freezer, and immediately tap it, as well as run your screw through it. I have done this before, and our 80oz steppers were able to turn it.

victorbl
01-13-2005, 01:42 AM
BobLWeiss: I've attached a picture of the ACME tap for reference, I can't get a good angle of my Delrin nuts where they are at right now, but there are tons of examples all over the forum

The flange bearings that secure the opposite end of the ACME lead screw arrived today. I did look into doing the 'trapped bearing between the washer and bolts', but the time and effort it would have taken, it just seemed worth it to spend the $8 per flange on a heavy duty model/prebuilt solution. I ended up with these:

<a href="http://www.surpluscenter.com/item.asp?UID=2005011300283080&item=1-201-08-4&catname=powerTrans">1/2" 4 Bolt Flange Bearing</a>

Once I opened up the package, I realized they were pretty over engineered for their purpose, but I have to say that they are extremely solid, zero play in any direction, and roll very smooth. I did have to trim down the X axis mount because sitting square it peeked just over the edge of the table, possibly interfering with the X axis table (It's just test fit in the picture, which is why it doesn't have bolts yet).

I did make the decision tonight after constantly tweaking the bronze bushings for the drill rod that I'm just going to order the UHMW replacements. One minute, I'm cruising the Y and Z axis around with the motors, and the next, it will catch on the slightest bit of friction and cause some serious missed steps. I could either try and spend the next week killing myself trying to correct the recurring problems, or I can just replace them and have a better chance at getting significantly less friction.

This weekend...it's paint time.

BobLWeiss
01-13-2005, 08:25 AM
Did you cut the drill rods to length? If so what did you use to slice through those?

Thanks for the pictures and explanations!!! I hope your sticking problem gets solved. I would rather use the bushings instead of roller bearings.

mvaughn
01-13-2005, 12:15 PM
I'll try to make 3 seperate replies in one message...


Hobbiest,

I can imagine that the UHMW will contract a little when frozen so that the tapped hole is slightly larger when thawed... Is there another reason for freezing? ie. Do the threads cut better when cold?



Victor,

Thanks for posting a picture of your ACME tap. That is how I imagined it but it is always nice to have a picture for reference.

I'm considering ordering flange bearings like yours instead of trying to engineer some of the trapt bearings you mentioned. They seem like a great price and much less hassle.

I can't wait to hear your opinion on the UHMW flange bearings your are ordering. I went a similar direction with my machine, except I hand made the bearings. They have been tricky to get aligned... (probably because they are hand made).



Bob,

I can't speak for Victor but I cut my 1 inch drill rod with pneumatic cuttoff wheel I purchased from harbor freight for 10 dollars USD.

mvaughn
01-13-2005, 12:36 PM
Victor,

Are you using a single flange bearing for each lead screw, or one on each end?

BobLWeiss
01-13-2005, 12:48 PM
Where can you get this "Delrin" stuff at in small quantities to make the nuts with? Does anyone here wish to make any for some $$? I am going with the same thread size and 1" drill rod for X, and 3/4" for Y and Z.

Let us know how those flanged bearings work out...got my fingers crossed for ya!

victorbl
01-13-2005, 02:13 PM
BobLWeiss: I'm mostly a woodworker, so when I went to try and cut the 3/4" drill rod with a hacksaw and a dremel with a cut off bit, it was pretty much a joke. I must have spent 30-45 minutes on one one. And even after all that time it was slightly uneven, and not to pretty. So, I broke down and went to a friends shop at work where he had a metal lathe. I have to tell you, it made the cleanest cut I have ever seen (see pics of of the end flange bearing, those are the cut ends of the drill rod), and each cut only took about 5 minutes without any manual labor.

mvaughn: I hope the UHMW flanged bushings work out as well. I went ahead and ordered replacements for all my drill rod bushings last night from mcmaster, so I expect they will be here on Monday or Tuesday. Stay tuned and I'll post how well they work so you'll know if they are worth the purchase or not.

As for the flange bearing at the end of my ACME screws, I'm only using one per axis...I use the motor with a flexible coupler to support the other end. I'm sure there are mixed opinions about using a bearing on the motor side of the screw as well, but I find that between the drill rod supporting the axis, and the flange bearing holding the screw on the opposite side....the ACME screw at the motor mount pretty much just floats in place w/o the motor even supporting it.

For your Delrin, Bob, I ended up ordering part number 8662K642 from mcmaster. It's a 1" Thick, 2-1/2" Wide, 12" Length bar for about $25. It's not a steal, but you can get your 3 anti-backlash nuts out of it, and still have enough for 2 to 3 extra nuts when/if your originals ever wear out. I just cut mine down to size with a table saw, but it's soft enough that a hack saw would slice it in no time as well.

While it is a little bit of work, there is an advantage to making your own Delrin nuts versus having someone else do it. If you use your home made ACME screw tap on the Delrin, you can rest assured that the threading in the Delrin will match your ACME screw threading exactly since it was cut from the same mold essentially.

mvaughn
01-13-2005, 03:13 PM
I keep coming up with tons of questions....

What type of flexible coupling are you using for you lead screw to motor connections?

Do you have a link or partnumber to a site that has affordable prices?

victorbl
01-13-2005, 03:53 PM
Keep the questions coming :)

I looked at a few different coupling options. I initally had one of the 1/2" ACME screws drilled with a 1/4" hole and a set screw...but I found that it was just the slightest bit misaligned, and would cause the opposite end of the screw to whip around. I figured once I put the flange bearing on the other end...this misalignment would just screw up my stepper motors.

So, I then looked at doing the flexible hose from Lowes, but found that it would be hard to join the ACME rod to the motor shaft since they were different diameters (1/2" ACME to 1/4" stepper).

I knew a solid coupler was not going to be good because it went back to the misalignment problem...my machine probably isn't to the accuracy of a professionally machined metal CNC, so I broke down and bought three Helical Beam Couplings - Part number 6208K125 at mcmaster. They are $25 a piece...which wasn't fun, but I have to say, they should be worth every penny. They are backlash free when rotating, but will allow the ACME rod to flex up to 3 degress I believe (seems like more). On the flip side, they also allow the rod to be pushed and pulled around, so make sure you have a solid flange bearing on the other side of the ACME rod(or whatever your solution) to prevent this motion.

This was the one part that was probably the most expensive (sans the motors), but I can say that you get what you pay for.

mvaughn
01-13-2005, 05:08 PM
Victor, what drill size did you use on your lead nuts before you tapped them. I'm going to measure the minor diameter of my ACME thread when I get home, but I'd like something to compare it to.

thanks,

BobLWeiss
01-13-2005, 05:48 PM
Thanks for the part numbers and places to buy from...saving me a ton of work.. I would say since the coupler is VERY important to all this and alignment issues are sure to crop into it, your choice should work out nice. How much have you used your machine so far? Besides the occasional binding are they any other problems you are encountering?

Bob

victorbl
01-13-2005, 07:42 PM
mvaughn: I honestly can't tell you the exact drill bit size. I have this insanely big drill bit set <a href="http://www.grizzly.com/products/item.cfm?itemnumber=G3658">bought here</a> that I got on special for $30 a few months ago. So I first made my ACME tap...then used a dial caliper to measure the diameter of the ground down rod where the threads had been filed off. I then just went through the bits with the caliper till I found a very close match. I guess I should have written that down. Sorry!

BobLWeiss: Unfortunatly I haven't used the machine once yet. The brass bushing problem is bad enough to make me want to wait for the UHMW bushings before I even try to tackle any cutting. They probably won't arrive till Monday or Tuesday, so it gives me a good excuse to tear the whole thing apart this weekend for painting. This must be my punishment for spinning the motors early ;)

You better believe that I'll start posting pics (and other problems) the minute I start cutting anything.

lerman
01-13-2005, 09:19 PM
Victor, what drill size did you use on your lead nuts before you tapped them. I'm going to measure the minor diameter of my ACME thread when I get home, but I'd like something to compare it to.

thanks,
There are several types of Acme thread -- I'll assume we're talking about "General Purpose Acme Single-Start Screw Threads." From Table 2a on page 1796 of the 26th edition:

D = Basic Major Diameter and Nominal Size, in Inches
P = Pitch = 1 divided by the Number of Threads per Inch.
E = Basic Pitch Diameter = D - 0.5P
K = Basic Minor Diameter = D - P

External Threads (Screws)
1 -- Major Dia. Max = D
2 -- Major Dia. Min = D minus 0.05P but not less than 0.005
3 -- Pitch Dia. Max = E minus allowance from Table 4
.... more stuff omitted...

Internal Thread (Nuts)
7 -- Major Dia. Min = D plus 0.020 for 10 threads per inch and coarser and 0.010 for finer pitches.
8 -- Major Dia. Max = Major Dia. Min (Formula 7) plus 0.20 for 10 threads per inch and coarser and 0.10 for finer pitches.
9 -- Pitch Dia. Min = E
10 -- Pitch Dia. Max = Pitch Dia. Min (Formula 9) plus tolerance from Table 5
11 -- Minor Dia. Min = K
12 = Minor Dia. Max = Minor Dia. Min (Formula 11) plus 0.05P but not less than 0.005.

Table 5 -- since this only relates to pitch diameter, it isn't relevant for the purpose of chosing a drill.

You will want to use a drill of size minor dia min = K = D - P [that's the diamter minus the pitch].

Because of issues like tolerances and clearances, it probably (I haven't looked at this closely) is NOT correct to just use your acme thread as a tap. But experience (as related here, not my own) says that it works just fine.

As I said, Machinery's Handbook is your friend. Everyone should have a copy (and if I could find the copy I have on CD, I might not have had to type this stuff in).

Ken

victorbl
01-14-2005, 04:36 PM
Is it me, or is the worst part of building an MDF/wood CNC the painting? Last night I spent an hour or so disassembling everything, and I can't help but think I'm going in the wrong direction :)

Anyways, I primed all of the MDF with shellac, and am planning on picking up some paint to help seal it up for good. Any suggestions on a paint type. I was leaning towards an exterior latex paint, but I've read in some posts that this tends to leave a rough finish. With that knowledge, I think I'm going to shop for the Rustoleum Hammered Paint.

If you have a better suggestion, please let me know. I'll probably just go grey for the whole thing.

mvaughn
01-14-2005, 05:01 PM
I went with the Dark Gray Rustoleum on my contraption and if I were to do it all over again, I'd go with a lighter color. I really don't have a reason, just that it seemed too dark.

victorbl
01-16-2005, 11:42 PM
We had a good bit of rain this weekend so painting outside was not such a hot idea. I ended up building a make-shift spray booth that ventelated the fumes/overspray to the outside of the garage so I could get a few coats of paint on it.

Some words of advice I've picked up in my construction/painting of an MDF machine...
* Try and keep screws away at least an 3/4" away from the edge of an MDF joint. Even with predrilled holes, and using confirmat screws, I still got hairline cracks in some areas where I was closer than 3/4" to the edge. You can fix this with a little wood glue and some clamps, but best to just avoid it all together if possible. Painting it really makes the cracks stand out.

* If your not going to prime your MDF with shellac or primer before painting it, use and electric sander on the exposed edges before you paint. I found that the edges that were reasonably sanded only needed one coat of paint as it wouldn't quickly soak into the MDF. Unsanded or unprimed edges of the MDF would require at least 3 coats before it would stop soaking up the paint. Trust me, a little time sanding or priming before saves you alot of time applying multiple coats later. The sanding helps clog the 'pores' in the MDF.

So enough on the advice. I took your advice mvaughn and went with a light machine grey as my color of choice. I used three cans of Rustoleums Industrial Enamel from Home Depot. It worked great, and seems to be a little more durable than the typical rattle can paints. It also didn't have the texture that the Hammered paints did which worried me on surfaces where the bushings would be against, as well as the router and X axis table tops.

UPS tracking tells me that the UHMW bushings arrive tomorrow, so with any luck I'll have it up and going this week! I'm psyced!

ger21
01-17-2005, 07:26 AM
You can use drywall compound or spackle to fill in those cracks, and also fill the pores on the edges

mvaughn
01-17-2005, 02:14 PM
Very nice work Victor.

I ordered a set of the flange bearings you used. I'm not sure when they will arrive, but hopefully they will motivate me to finish my cnc router.

BobLWeiss
01-17-2005, 06:58 PM
I went with the Dark Gray Rustoleum on my contraption and if I were to do it all over again, I'd go with a lighter color. I really don't have a reason, just that it seemed too dark.


That is comming out really well. Good job. I guess everyone has a preference because I love that color..looks almost like its made of aluminum. You made your own bushings out of that plastic? How is working out? Any binding at all?

victorbl
01-17-2005, 07:26 PM
Thanks for the support. Yea, I was really tempted to maybe do a yellow/black color scheme on the pieces in the DeWalt style, but I figured that's probably more work than it's worth...the light grey seemed like the right choice.

My plastic bushing shipment is delayed for MLK, so probably won't get those until tomorrow. mvaughn, I guess you'll need to add some MDF blocks to hold your newly ordered bushings? Or at least drill some holes in your existing design?

mvaughn
01-17-2005, 10:57 PM
That is comming out really well. Good job. I guess everyone has a preference because I love that color..looks almost like its made of aluminum. You made your own bushings out of that plastic? How is working out? Any binding at all?


The home-made bushings work very nicely. It took a little effort to get them aligned so they wouldn't bind, but now they glide quite nicely.

mvaughn
01-17-2005, 10:59 PM
mvaughn, I guess you'll need to add some MDF blocks to hold your newly ordered bushings? Or at least drill some holes in your existing design?


I haven't ordered any of the bushings yet... I ordered the flange bearings for my lead screws

victorbl
01-23-2005, 02:05 AM
She lives! After spending the past two days familiarizing myself with TurboCNC, and doing a few test plots with a ball point pen, I've finally made my first cuts!

To play a little catchup, I recieved the UHMW bushings from mcmaster, installed them, and they make a HUGE difference. My X axis table had the worst friction to the point that it took a reasonable amount of force to start moving it using the oilite bushings. Now, I can literally slide the X axis table with just a slight amount of force from my pinky finger. My only gripe (and not that big of one) is that while the 3/4" UHMW bushings are a perfect fit with no play, the 1" bushings on the X axis have just a tiny bit of play in them. I can correct it by simply adjusting the drill rod to 'bind' out the play, but just thought I would let you'll know it exists. However, once the drill rod is adjusted, I do not feel the play in the X axis.

For now I am using a DeWalt cut out tool (their version of a roto-zip) that I wasn't using in my workshop. It's extremely solid, but incredibly loud. It isn't variable speed, so there isn't any room for adjustment. I also have a variable speed DeWalt router that is much quieter, so I may find myself cutting a mount for it tomorrow with the CNC....such an amazing thought...the machine cutting it's own parts. Any suggestions for a quieter tool (other than building a spindle)?

You can see the first test cut I made below...just used a 1/16" end mill, and engraved some text at 0.1" depth.

I have some switches lying around that I would like to install for limits/home....but I think I'll build a router mount, an electronics enclosure, and some fun parts before I get around to that. :)

ger21
01-23-2005, 07:47 AM
Any suggestions for a quieter tool (other than building a spindle)?




Get a router speed control. I think Harbor Freight has them for about $20, most woodworking suppliers have them as well, but you'll pay more. Those rotozip type tools (and laminate trimmers) usually spin at 25000 to 30000 rpm. With a 1/4" tool, 15 to 18000 would probably work better( you'll get less burning), and should cut the noise quite a bit. You may find when you start cutting, that the actual cutting may be louder than the motor. Especially if your tooling isn't sharp.

victorbl
01-23-2005, 11:31 PM
Thx for the advice, I'm experimenting at the moment with different cutters. I used my quickly hacked together mount and Rotozip tool (see pics from previous post) to cut a new base and mounting blocks for my 2 1/4hp router. It's variable speed so I can control things a bit better, and it's significantly more quiet. There was a little play in the cheesy rotozip mount I built, which translated into a tiny amount of offset in the second cutting pass of the router mount. You can see the small line on the upper router clamp. No worries though, the router clamps I had the machine create are more true than I could have ever cut in a reasonable amount of time.

On the down side, the router collets only go down to 1/4", so I"ll need to order a 1/4" -> 1/8" adapter before I do any detailed cutting.

It's unbelievable how much dust is generated from cutting MDF with the milling bits, so I think my next project is going to be integrating dust collection into the design. I am planning on building a similar setup to Beezer's (<a href="http://www.cnczone.com/gallery/showphoto.php/photo/763/sort/1/cat/500">see pic</a>)

If anyone is interested in the DXF's of the router mounts, I'm happy to post them on request. They were measured for a DeWalt DW618 style router.

MrBean
01-23-2005, 11:40 PM
Looks very nice, but what I really want to know is..............Does that SuperSprint arcade machine still work. That was one of my faves. Was a while ago tho'.

Regards Terry.....

mvaughn
01-23-2005, 11:53 PM
Hey victor... looks great!

What is that steering wheel atached to in the second pic in your last post? Is it an arcade cabinet?

Kudos to you!

mvaughn
01-24-2005, 12:10 AM
oops... looks like Terry beat me to the punch.

edbo68
01-24-2005, 12:46 AM
Great Job!

1) What did you use to hold down the work you routed/engraved?
2) It looks like you have square steel tubing under the table. Is that for ridgid support?
3) what is the dimensions of your machine? You only gave us the work area

Keep up the good work! and keep us posted!

victorbl
01-24-2005, 12:49 AM
MrBean: Yea, that is indeed a working 3 player Supersprint. Fantastic game...every party we throw at the house always seems to end with a group of 5 or 6 tipsy people playing Supersprint for hours. It sits in the garage with it's friends Ms Pac, Dragon's Lair, SmashTV, and a few others...

Hey mvaughn, have you had a chance to fit the new flange bearings on your machine? I'm extremly pleased with mine, and the price was right considering they don't have a bit of play in them.

mvaughn
01-24-2005, 12:54 AM
Hey mvaughn, have you had a chance to fit the new flange bearings on your machine? I'm extremly pleased with mine, and the price was right considering they don't have a bit of play in them.

Nope, the flange bearings haven't arrived yet. They will be here monday afternoon due to a weather dalay last week.

Your arcade collection sounds awesome. When I finish up a few of my already in-progress projects I will build myself a Mame Arcade cabinet.

victorbl
01-24-2005, 03:04 AM
1) What did you use to hold down the work you routed/engraved?
2) It looks like you have square steel tubing under the table. Is that for ridgid support?
3) what is the dimensions of your machine? You only gave us the work area

1) I just used carpet tape to hold the MDF down. It's very strong, and does a good job of holding the 'cut out' piece in place without it shifting around once it has been cut free of the wood.

2) It's 3/4" aluminum tubing that I picked up from Home Depot. I'm using it to hopefully help prevent my X axis table from sagging over time.

3) It's 29" wide by 36" long and 28" high

mvaughn
01-25-2005, 01:26 PM
If anyone is interested in the DXF's of the router mounts, I'm happy to post them on request. They were measured for a DeWalt DW618 style router.

What is the diameter of your DeWalt Router? If it is 3.5 inches, I would be interested in the DXF's

victorbl
01-25-2005, 11:49 PM
The router does have a 3.5" diameter. I'm starting to notice that there are alot of routers out there with that dimension. I realize that the shape isn't perfect for everyone's design, but it's sometimes better than starting from scratch!

Ninjak2k
03-23-2005, 01:20 PM
victorbl, beautiful machine you have there. I was hoping you could elaborate on any process you went through aligning the drill rods and bushings for minimum binding. I like the idea of using these bushings over a roller blade bearing setup. Also, are you using any lubricant on your rods?

I just have to figure out how to cut drill rod without a machine shop. I was hoping a dremel cutoff wheel or hacksaw would work, but your earlier experience put an end to that idea. I need to find a new friend with tools, I guess. :p

Oh, your posting of part numbers and places to buy them as just been invaluable. Thanks so much for doing that.

Cheers,
Dan

mike hide
03-25-2006, 11:00 PM
Is it me, or is the worst part of building an MDF/wood CNC the painting? Last night I spent an hour or so disassembling everything, and I can't help but think I'm going in the wrong direction :)

Anyways, I primed all of the MDF with shellac, and am planning on picking up some paint to help seal it up for good. Any suggestions on a paint type. I was leaning towards an exterior latex paint, but I've read in some posts that this tends to leave a rough finish. With that knowledge, I think I'm going to shop for the Rustoleum Hammered Paint.

If you have a better suggestion, please let me know. I'll probably just go grey for the whole thing.

Automotive grey primer looks good...

joecnc2006
03-26-2006, 04:22 AM
victorbl, beautiful machine you have there. I was hoping you could elaborate on any process you went through aligning the drill rods and bushings for minimum binding. I like the idea of using these bushings over a roller blade bearing setup. Also, are you using any lubricant on your rods?

I just have to figure out how to cut drill rod without a machine shop. I was hoping a dremel cutoff wheel or hacksaw would work, but your earlier experience put an end to that idea. I need to find a new friend with tools, I guess. :p

Oh, your posting of part numbers and places to buy them as just been invaluable. Thanks so much for doing that.

Cheers,
Dan

I cut my drill rod with a cutoff wheel installed in my circular saw, then grind ends at a slight bevel.

Here is my Hitachi Router mount, you can just change the radius, its 3.32 right now.

JavaDog
03-26-2006, 06:50 AM
The router does have a 3.5" diameter. I'm starting to notice that there are alot of routers out there with that dimension. I realize that the shape isn't perfect for everyone's design, but it's sometimes better than starting from scratch!

I am using the same exact router as the spindle for my machine. Oh, these templates are going to be handy! You just saved me some work...

BTW - How do you like that router?

spalm
03-26-2006, 10:39 PM
Nice looking machine,

I see you separated the two router mounts. I did the same on my first machine. I found it allowed a little flex. On my second machine, I basically glued them together and added a triangle support. This gives me more adjustment to move the router up and down, and a bit more strength, but I found that I can mount the router with a bit of a tilt, and takes a bit of fiddling to get it straight up and down.

Just thought I’d throw in my $.02 worth.

Steve