for a machine that will see light use, would it make sense to make a mount for the steppers that attaches to the existing bearing blocks (where the vernier and the hand wheels attach) and use the existing ACME screws?

Could Derlin nuts be used to take out back lash and reduce friction?

I'm thinking that I could get the rig up and running and then convert it to ball screws in the future?

I'm aware of the basics.... that ball screws are MUCH more efficient. But I don't feel the need to operate the mill at super sonic speeds. And if I could get, say, 500 hours out of it milling aluminum, before the ACME screws show wear in the centers, then I could justify the add'l cost of upgrading the screws.

I'm basically stuck, trying to do this project on a shoe string budget, because it's a hobby thing for me and I can't justify dropping a lot of bread on it.

thoughts?

opinions?

any body else out there done it?

It can certainly be done. Make the nuts adjustable (split the brass nuts), and get used to adjusting them periodically, and it'll work just fine. You should really design the whole conversion, and just assume the ballscrews will bolt in just like the leadscrews, and you'll be able to easily add them at any time.

Regards,
Ray L.

Thoughts-
1) Yes it can be done
2) Delrin might help increase the efficiency of the screw - ACME's are much less efficient than ballscrews, but I don't know if a delrin block itself can handle the forces of metal machining with out deforming or otherwise becoming un-mounted.
3) You're stuck with trouble selecting appropriate stepper motors. You need more torque because of the lower efficency but this might be offset by the higher pitch of the ACME screw. But the higher screw pitch will require more speed and unfortunately the nature of steppers causes them to lose torque as the speed increases. Servos would alleviate that problem but then the price increases.
4) The stock bearing setup is terrible for backlash. I don't know if you can design up a mount that replaces the stock bearings with suitable replacements with the existing screws.

Nothing says it can't be done but there are obstacles - just making sure you're going in with your eyes open. There may be other items to consider, be patient and you should get some more replies.

Hi Matt,

I'm sure it could be done too. I read a thread somewhere around here where the person was actually getting pretty good results in regards to the backlash.
I would stick with the brass nuts also.


Now when those acme screws wear out....I'm sure I could find you at least one replacement set at a really cheap price. :) I converted mine to ballscrews like everyone else. (I bet there are acme screws just laying around.)

I will see if I can hunt that thread down for you.

Cheers,

Hello Matt,

Like you I wanted to start out as low cost as possible so I built mine around the ACME setup. I used the same motors and other electronics that I would use with the ball screws so that in the future I could go that route. I based my entire system off Cadmonkey's design but when it came to attaching the motors to the ACME screws I ended up having to make the brackets and whatnot on the fly - all except the z axis.

I put the x axis stepper on the motor side of the mill, connected it to a solid coupler, and keeping the stock bearings and hand wheel setup. The y axis I did use bearings but the ACME screws have a 12mm diameter shaft to connect the motor to and I didn't have a lathe at the time to modify the shafts so I just got 12mm ID bearings and made the bearing and motor mount around those.

I don't know if the Z axis really needs the 2.6:1 pulley reduction in Cadmonkey's plans but I wasn't going to chance it and set that up as in the plans. The only thing I changed was the size of the shaft hole in the larger pulley to 12mm to fit the stock ACME screw.

What I found from doing this is I would get 60 IPM rapids on the x and y and 15 IPM on the z. Rapids aren't an issue using the ACME screws if you can handle these speeds. You may be able to get better rapids on the z if you go 1:1 since the stepper motor torque increases the slower it moves. I hope to go to 1:1 when I get the ball screw in the z.

I'm working on changing over the ACMEs now because the average backlash off all the axis was about .005". I cut a larger radius in aluminum and these seem to show the effects of the backlash even with the backlash compensation in the software. If you cut the metal (more pronounced in the conventional direction than the climb) you get a see-saw effect where the table moves in the available .005" leaving divots in the metal to sand out. I could get the backlash down to .003" but that wouldn't last too long and would soon climb back up to .005" If you can deal with this backlash I would recommend using the stock screws but I can't spend a lot of time sanding out divots to smooth the metal for chroming. Quality sandpaper is also upwards of $1 a sheet too.

As far as cutting speed it doesn't matter which setup you use. My normal cut with .5" 2 flute HSS end mill was 10 IPM at .05" DOC. I could probably go deeper or faster too but I hadn't gotten that far yet. The biggest hold-back is spindle speed.

Anyways good luck,

Rick

Hackmax - Do you have any pics or drawings of what you ended up doing? If you could post them, or PM me for an email address to send to. If you don't mind I'd like to show some pics of how others have modified the plans to suit their needs - financial, phased implentation, etc. Thanks.

Also - with the ACME screws you can definitely go 1:1 on the Z, or even a step-up ratio. I know the 2.6:1 is overkill and I may end up going to a smaller ratio in the future to get better rapids. I rapid around 30 safely but that is a limit induced by my PC - it just can't send quick enough pulses for microstepping. With 16tpi ACME vs 5tpi Ballscrew, you've already got 3x the advantage. When you do install the ballscrew on Z if you go 1:1 then be conscious of backdrive when powered down - you may need to add a gas strut as I believe comes standard on the SuperX3 - this was part of my decision to go with the 2.6:1 - the natural cogging of the motor when coupled with a high ratio to the screw was sufficient to eliminate backdriving, even if I loosen the gib nearly to removed.

I toyed with the idea of doing Z on the ACME screw when I got the X and Y done since the Z didn't seem to all that have much backlash with the gearing of the front handle taken out of the equation, but since I had the Z ballscrew in hand since I had ordered a stock 6' length it wasn't worth the time to put AC bearings on the ACME. I do want to go to a preloaded double nut on the Z though - there's enough backlash with a single nut that I am not satisfied with and the best DIY double nut setup I can envision would loose some top end travel which I refuse to give up. The factory double nut is just longer than the standard nuts I used so it runs into the area that is at the bottom end of the travel that never gets used. That upgrade will wait for tax refund to come, doctor bills from the Cleveland Clinic to start showing up so I know how much they charge vs what my insurance covers and whether or not I am able to stay employed with my decreased performance under the diagnosis I have finally gotten from the high quality care in Cleveland. (eg - there are a lot of variables that need to be evaluated before I buy a $300 ballnut (IIRC) so that is VERY back burner). I am curious what size steppers you ended up using that are suited to ACME and ballscrew?

I know the stock 'adjustable' brass nuts were constantly in need of adjjustment while I was machining the parts and I ended up putting on digital scales to be able to machine accurate enough for the parts to come out with centerlines where they needed to be. And that was manual where speeds aren't as demanding as the speeds you'll see on CNC or loads with cutting forces involved.

Hackmax - Do you have any pics or drawings of what you ended up doing? If you could post them, or PM me for an email address to send to. If you don't mind I'd like to show some pics of how others have modified the plans to suit their needs - financial, phased implentation, etc. Thanks.

Also - with the ACME screws you can definitely go 1:1 on the Z, or even a step-up ratio. I know the 2.6:1 is overkill and I may end up going to a smaller ratio in the future to get better rapids. I rapid around 30 safely but that is a limit induced by my PC - it just can't send quick enough pulses for microstepping. With 16tpi ACME vs 5tpi Ballscrew, you've already got 3x the advantage. When you do install the ballscrew on Z if you go 1:1 then be conscious of backdrive when powered down - you may need to add a gas strut as I believe comes standard on the SuperX3 - this was part of my decision to go with the 2.6:1 - the natural cogging of the motor when coupled with a high ratio to the screw was sufficient to eliminate backdriving, even if I loosen the gib nearly to removed.

I toyed with the idea of doing Z on the ACME screw when I got the X and Y done since the Z didn't seem to all that have much backlash with the gearing of the front handle taken out of the equation, but since I had the Z ballscrew in hand since I had ordered a stock 6' length it wasn't worth the time to put AC bearings on the ACME. I do want to go to a preloaded double nut on the Z though - there's enough backlash with a single nut that I am not satisfied with and the best DIY double nut setup I can envision would loose some top end travel which I refuse to give up. The factory double nut is just longer than the standard nuts I used so it runs into the area that is at the bottom end of the travel that never gets used. That upgrade will wait for tax refund to come, doctor bills from the Cleveland Clinic to start showing up so I know how much they charge vs what my insurance covers and whether or not I am able to stay employed with my decreased performance under the diagnosis I have finally gotten from the high quality care in Cleveland. (eg - there are a lot of variables that need to be evaluated before I buy a $300 ballnut (IIRC) so that is VERY back burner). I am curious what size steppers you ended up using that are suited to ACME and ballscrew?

I know the stock 'adjustable' brass nuts were constantly in need of adjjustment while I was machining the parts and I ended up putting on digital scales to be able to machine accurate enough for the parts to come out with centerlines where they needed to be. And that was manual where speeds aren't as demanding as the speeds you'll see on CNC or loads with cutting forces involved.

Hey Greg I got started on it and it got big and is more appropriate to be placed in your thread. (http://www.cnczone.com/forums/showthread.php?t=59321)

Edit: Oops almost forgot the rest of what you wanted to know. I used the same size steppers as you did because I knew I would be going to ball screws eventually.
Also I'm almost positive the z axis is a 2:1 from the hand wheel and is a 10 TPI screw.

Rick

Gentlemen,

Thank you all for your insightful responses.... the chances of me pulling this conversion off are greatly increased by keeping the cost minimal.

CAD Monkey's plans are top shelf and I thank you very much for sharing the Solid Works files..... but I think I'm going the KISS route. Two reasons....
1.) lower cost and 2.) maximize my chances of getting it right.

Here's a link that shows how I'd like to do the X and Y Motor mounts....
http://www.jeffree.co.uk/pages/x3-to-cnc.html

One of the things I like a lot about this approach is that by sticking with the ACME screws and using a dual shaft motor, I can put the handles back on the shafts and be have easy dual use as both manual and CNC.

One of my concerns is that the weight of the steppers will put quite a bit of downward force on the neck of the factory bearing seat. Hmmmmm? At least two guys have done it this way, as Tony Jeffree's design is a modification of this one by Dick Stephen.
http://www.arceurotrade.co.uk/projects/X3-CNC/X3_Article_Part_2.pdf

But can these Brits be trusted? After all, they did abandon their offspring and jump on the SI train.

Other thrifty and neat feature I like are...

Jeffree's machined his ball screw adapters out of the ACME screws, which will require no mod to the bearing and motor mount if I upgrade.... Well, assuming I don't add an ATB, which I really should.

Stephen's machined out the existing ACME threaded brass nuts to mount his ball nuts. Another plus for thrift and easy upgrading.

As for dealing with back lash and adjustments.... here's my idea....

machine out the existing ACME threaded brass nuts to accept a ball nut, but then face mount one of dumpsterCNC's anti backlash/automatic wear compensation Delrin lead nuts. http://www.dumpstercnc.com/datasheets/datasheet_ableadnuts.pdf

And since I'd be drilling/turning out the AMCE threads on the existing brass nut, if I had my ducks in a row and knew exactly what the thread details on the future ball nut were, I could possibly cut the threads into the brass nut up front and not even have to remove the brass blocks should I decide to upgrade, because the dumpsterCNC AB nuts would be mounted by drilling through the flange.

As for the Z-axis.... I really admire the CNC fusion design. I think it's well thought out and like the idea of not having to do any machining on the factory castings.

But there again.... I've got my own half baked idea... by going with a top mounting motor, driving an extension off of the existing ACME screw, couldn't I keep the gears on the bottom in place and again have a dual use (manual/CNC) set up?

But then again, I guess I could easily jog the head down by eye and use the quill for drilling/tapping. If the quill was only extended a small amount and then locked, would this be stable enough for milling?

And heres my really stupid question .... I realize that if there is power going to the steppers, they will be locked into position. But is there any way turning a de-energized motor can send pulsed back into the controller software to indicate position?

And my final cheap skate idea.... I put another thread up about using an Anaheim Automation drive pack (800W ps, 7amp hold, unipolar, bi-level drive that supports only full or half stepping). With the pitch on the ACME screws, could I get decent results (smooth, vibration free cutting with a resolution of .001) with half stepping?

Sorry to go on... that's a lot to process, I know.

Thanks again for your taking the time to read this and comment.

Yes you could top mount the Z and keep the handwheels. Be forewarned - mentioning keeping the handwheels on converted machines can start a flame war around here... I'll just say this - keep in mind the wheel is at just the right height to knock you in the *^$s when you're running under automatic control... You can do manual work with the CNC software either by jogging or entering in G code on the fly. You can have the quill extended and locked a bit and still be rigid enough, just not too far, especially with larger cutters. If you want to send pulses back with steppers you need to add encoders onto the shaft and read those - just like servos do (though some servo drives don't route the encoders back to PC, they just throw a fault when they haven't seen the complementary amount of movement as has been commanded). I don't know what results 1/2 stepping would yield on the ACME screws as far as resonance and resolution go. Sorry.

a couple things that you might wanna think about, adding the hand wheels on the back end of the motors is a neat idea, i thought about this myself, till someone pointed out that the handels aren't ballanced, and will add vibration to the system when in cnc mode.

something else to think about, by keeping the z axis hand wheel, again ballance, and you will be adding more load to the z axis system, meaning that it will take more torque to turn the screw. I would also think that this would add a considerable noise component as the gears for the z axis arent exactly what i would call perfection.

Michael over at cnc fusion is a really great guy and really helped me out when i did my conversion. we emailed back and forth i dont know how many times, untill i fully understood what i was dealing with. The fact that he's basically my neighbor didnt hurt his running in the decision on what product to go with as well(hes just a couple hours down the road from me)

extending the quill down for milling operations is not something i would suggest, it adds more lever action to the whole machine and could introduce additional flex and possibly more chatter when machining. Mine is in the upright and locked position and thats where it stays.

feeding back to software from the motors would need to be handeled by an encoder, or some kind of DRO unit. I suppose if you really wanted to get off into it, you could work up the electronics to try and feed back the motor pulses, but the problem is going to be when you land between steps, or just hit a step but then rock back to the previous detent, this will introduce errors... not to mention that as speed changes, voltage out will change, and this could effect the sensing.

not to mention that depending on the drivers your using, feeding back when thier not on could cause the drivers to fail.

really the only way to do it reliably is with encoders or a dro. go and get yourself the mach 3 instruction book, it talks about doing just that.... http://www.machsupport.com/docs/Mach3Mill_Install_Config.pdf start on page 52 of the pdf, section 4.10 linear encoders.

half stepping a 200s/r motor, with a 10tpi screw gives .00025 inches per step,
2*200*10=4000steps/inch
your main issue os going to be resonance in the motor. half stepping has issues at certain rpm's of the motor/screw/coupler system. resonance is a bad thing when talking about stepper motors, and should be reduced and or avoided if at all possible. it can cause lost steps, which translates to messed up parts, and or possably worse, much worse depending on how bad it is. (can you say crashing the endmill into the table?)

the other problem is gonna come in when you convert over to the 5tpi screws, it'll drop your resolution to .0005 per step. if this is an acceptable resolution, then ok, but if your doing some machining, say, a long low angle part, where the angle isnt parallel to an axis, say 5 or 10 deg off, then you may notice some resolution stepping. this probably wont be a major factor as we're only talking about a half a thou, but if you get into ultra precision stuff, or if theres some backlash in that axis' travel, it may become very evedent. on my system i'm running 200step/rev motors, 10 microstepping drive, 5tpi ball screws(cncfusion) and my theoretical resolution is .0001 and i'm more than happy, and i can still get rapids over 100ipm.

as for drivers, i'm running gecko 203v's, and i couldnt be happier. I love the "vampire" drives, cause you, and i'm quoting gecko here, you cant kill 'em. all sorts of safeguards, short protection, and stuff like that. if your not super on your game, you can blow up some of the other drivers out there, and all you did was sneeze hard. I gotta say, gecko makes a good product, and the 203v is my personal favorite. Keep an eye on the gecko site, they sometimes put thier stuff on sale(i happend to catch them on sale when i got mine)

something else, if your not already familiar with the terms resolution and repeatability, learn what they mean and the differences between them. i know that this was a hurdle when i first started into all this, and knowing the difference has helped me to become a better cnc operator.

I'll have to do some more homework and mull over "recycling" my AA drive pack and half stepping. I don't really understand what the difference is between unipolar and bipolar, nor between bilevel and chopper drives.

So I'm wondering if I could source stepper motors that would work with this AA drive, and then, if the resolution or resonance became an issue, could be set up to run off of a micro stepping drive like the Geckos. Assuming I didn't miswire and fry the motors, I could at least test out the AA drive pack that way.

I still like idea of setting up for dual use (CNC/manual) on both X and Y. Perhaps I could rig up the hand wheels in such a way that they could be quickly removed/installed.

Any body out there able to shed a little light on the topic of encoders? Specifically, are they expensive? Do most BOBs have hook ups for them? Do they mount on the back shaft? and if so, would I still have room left ot mount the hand wheels.

I do have quite a bit of experience jogging around on a CNC table router, as well as writing G-codes on the fly and entering them in at the command line. I find it to be a royal pain in the neck and that's why I'm so interested in setting up for "dual use".

I am going to punt the idea of keeping the Z linkage to the hand screw in tact.

Is it an expensive proposition to wire up a touch off? and do the populare apps like Mach 3 provide for that input? If I could easilly get my exact tool height entered after a tool change, then jogging or tapping in G codes to position Z would be a breeze.

Also, are there any big advantages or disadvantages to driving z from up top? There's obvioulsy going to be some drilling of good size holes involved, and you lose the ability to get any mechanical advantage via. the motor connection. Any others that I'm missing.

Any comments on mounting the X & Y steppers directly to the factory bearing seat?

Any one out there ever use the dumpsterCNC AB nuts?

thanks again,

I sure do appreciate your responses.

The easest way i can explain unipolar vs biploar is like this. Imagine you have a coil, like one in a motor, and lets call the connections to it a and b. you can apply power to it with a + and b -, or with a - and b +. in unipolar you pick one or the other and use it exclusivly. in bipolar, you use both all the time. thats the super simple version...

chances are that you can find motors that you will be able to use for both, and if you do mis wire something, i would think that it would be more likely to kill the drive than the motor.

if you can figure a quick release system for the handles, then i really dont see a problem with it, there are some that might "give you the business" about it, but its your machine, and if thats what works for you, then i say go for it. In my mind i picture somethng like a race car steering wheel release mech.

my experience with encoders is fairly limited, but what i do know is that they do need to mount somewhere on the shaft, i have seen far end encoders, and motor mounted ones. if you mount it on the motor, then i would think that it would go onthe back end shaft. If it were me, and i were considering getting and using encoders, i would just get the motors with them already installed, just to simplify my life. The other option would be to get the encoders, and mount them on the far end of the screw, but this has its advantages and disadvantages. Encoder pricing will depend largely on how many divisions it has, or how accurate its supposed to be.

one thing that you might consider is using a jogging pendant. I just recently saw one online for about $90 that was usb interface, and would allow you to jog each axis down to the single step.. I'm seriously considering getting one of these for my machine, as i sometimes would like the ability to operate in a "manual mode"

i wouldnt think that it would be very expensive to set up a touch off tool height system, i havent tried it yet, but i think its a great idea. Perhaps someone else can give us some input on this.

I dont see a major problem driving the z screw from the top, and if you wanted to get creative, i bet you could still set it up with some mechanical advantage...

i just came across this page, you might find it interesting, maybe not, but now you have the choice...

http://www.jeffree.co.uk/pages/x3-to-cnc.html

that's the same page I linked to in my origonal post....

that's exactly what I'm thinking of attempting, but with the stock ACME lead screws.

oops, missed that one.. sorry.
just trying to help

Well after reading up and finally talking to John at Keling, I've come to the conclusion that my Anaheim Automation Drive pack is NOT going to work out for me.... Just to many unknows and variables for my liking.

So in keeping with the KISS plug and play concept, I ordered a G540 today, while they still have the special price on their custom run overstock.... $225.

My plan is to run all three axis with the Keling KL23H284-35-4B 387 oz-in steppers, and to set up the Z-axis similar to how CAD Monkey has done, with ~2-1/2 : 1 mechanical advantage. I'm willing to live with the slower Z speeds, in favor of using the "no brainer" G540.

Let's just say the electronic end of the equation is where I'm the weakest :confused:.

Mill will be ordered early next week, as my wife aked me to finish up a painting project and move some furniture around before ordering the mill. (Her way of making sure I don't get distracted and leave the paining job undone).

More on my "salvage" power supply to follw.....

I know I'm giving up some performance.... but I think I'm going to be able to pull off the entire "basic" mill conversion (including the price of the mill) for less than $1,700.

Thanks to all of you for your input.

Matt

Capital plan Matt!

Remember though, that with stock Z lead screw you would already be geared 2:1 even if your pulleys were 1:1. You may not NEED as much gearing as 4.5:1. (2.5:1 + 2:1 of leadscrew) Or would that be 9:1?

If you are using 48-50V PSU, the 387s should run very fast. They are out of stock until 2/10 though. Be sure to specify NO SUBSTITUTIONS.

I hope this works out well for you and is finally a viable G540/X3 plan.

Are you also going to use the G540 spindle speed controller?

CR.

Are you also going to use the G540 spindle speed controller?

If it looks like it can be wired right into the mills standard speed control, and isn't two difficult to set up, I'd like to give it a shot. I know a read a thread that detailed how to do this (probably a post on the looooong CNC fusion kit conversion). But in all honesty, all the reading I've done in the past week is all jumbled around in my brain.

I needed to get the electronics end of the equation solved.

I need to dig into the details of my power supply (will post pics with notes on my voltage readings). Basically, inside the drive pack there are four controllers and a power supply with two coils. Each coil powers a pair of drivers and has 4 hot wires coming off of the windings. Two hot wires go to each driver and when picking the voltage between the two hots, it reads zero, but each of the hots reads 20 v DC when compared to either of the two neatral leads that go to the other side of the controller. The over all rating is 800 Watts with 10 amps/ phase max. operating current. So I'm guessing that each of the leads to the controller is a phase, and if I have 20 volts and a max of 10 amps, that's 200 Watts max. to each controller. So if I ditch the controllers and wire up the like phases from each of the p/s coils in series, shouldn't I get 40 volts with 10 amps/phase max.

This would be a little on the light side (as compared to 48 volts), but I'd be able to mount the G540 in the existing driver pack and have a tidy fan cooled package. And its FREE :)

Does this make any sense, or do I know just enought electical theory to be a hazzard to myself and others? :confused:

Yes it makes sense. Just make sure what you have before connecting the little Geezer.

CR.

The speed control should connect something like this:

http://cnc4pc.com/Tech_Docs/Sieg_X3.pdf

Just make sure you have an isolated 12V power supply for it.

CR.

Remember though, that with stock Z lead screw you would already be geared 2:1 even if your pulleys were 1:1. You may not NEED as much gearing as 4.5:1. (2.5:1 + 2:1 of leadscrew) Or would that be 9:1?
CR.

Crevice the z lead screw in the back is a 10 tpi screw. It is geared at the hand wheel shaft at the 2:1 ratio which Cadmonkey's plans doesn't use. The pulleys would turn the screw at a 2.6:1 ratio still.

Matt as far as the the stepper driving the z axis - this is the only place I wouldn't skimp. If John says it will work though it must be OK. Good luck on your project though - CNC is fun!

Rick

Crevice the z lead screw in the back is a 10 tpi screw. It is geared at the hand wheel shaft at the 2:1 ratio which Cadmonkey's plans doesn't use. The pulleys would turn the screw at a 2.6:1 ratio still.

Matt as far as the the stepper driving the z axis - this is the only place I wouldn't skimp. If John says it will work though it must be OK. Good luck on your project though - CNC is fun!

Rick

Cadmonkey used ball screws and drove THEM 2.6 to 1. Usually we are connecting the Z motor 1:1 to a 5 TPI ball screw. Connecting 1:1 to a 10 TPI screw equals 2:1 gearing compared to ball screws. Adding further 2.5:1 gearing to THAT will only slow the axis way down.

CR.

Also - with the ACME screws you can definitely go 1:1 on the Z, or even a step-up ratio. I know the 2.6:1 is overkill and I may end up going to a smaller ratio in the future to get better rapids. I rapid around 30 safely but that is a limit induced by my PC - it just can't send quick enough pulses for microstepping. With 16tpi ACME vs 5tpi Ballscrew, you've already got 3x the advantage. When you do install the ballscrew on Z if you go 1:1 then be conscious of backdrive when powered down - you may need to add a gas strut as I believe comes standard on the SuperX3 - this was part of my decision to go with the 2.6:1 - the natural cogging of the motor when coupled with a high ratio to the screw was sufficient to eliminate backdriving, even if I loosen the gib nearly to removed.

CR.

made quite a bit of progress painting (my prerequisite honey-do) two more evenings should knock it out.....

putting together my order list....

I wonder if Grizzly will send me a flat granite slab strapped to the top of the mill crate and wave the extra shipping?

I've done about as much planning and prep. as I can with out having the mill in front of my face to verify dims.

The bug has bit me somethin' bad :)

Well thanks to our economy being in the toilet, and sales being way down... Currently Grizzley has been offering FREE shipping on machines...

I would order now, there may be a backlog - or you might have it in a week.

G0463 isn't on the list....

only the big machines....

I hope this works out well for you and is finally a viable G540/X3 plan.


I've long admired this build as well as S_J_H's other creations
http://www.cnczone.com/forums/showthread.php?t=24983
to bad so many of the pictures have disappeared

He's getting 20 ipm on the Z using a Xylotex at ~24V and stock screw. Bodes well for a G540 at 48V.

Any body out there able to shed a little light on the topic of encoders? Specifically, are they expensive? Do most BOBs have hook ups for them? Do they mount on the back shaft? and if so, would I still have room left ot mount the hand wheels.

Sorry, I can't offer much help other than to say I have also developed an interest in this topic. The reasons for my interest are different however. USDigital has a nice selection, if a bit expensive.

You were warned the idea of manual control could start a flame war :) If you are planning to use the computer monitor as a DRO why not just use MDI or jog ? You've already gone to the trouble of firing up the computer for the DRO. Firing up the motors is just one step away. The motors will move the axis more smoothly and accurately than is possible by hand. Otoh manual control with the computer off might come in handy for a quick bit of work. The X3's quill could be a handy thing for drilling a quick hole.

thankyou every one for being kind and not flaming the new guy.

my disclamer is 1. I'm not a machinist and 2. I don't pretend to be one

My interest in manual control is based on my experience with a CNC table router. Transit and Jog run off of a keyboard, imho, suck! And I have had many times wanted to just cut a quick part on the router and didn't want to fool around drafting the geometry in Auto-CAD, crunching the g-codes in Bob-CAM, and then running the file..... just to put a dado into a part. At work, this is compounded by the fact that I have to run back and forth 100 yds between two buildings to get this done.

I am hoping to use the X3 for a diverse range of HOBBY related projects.... cutting mostly aluminum, brass, and hard plastics like HDPE, ABS and UHMW, and maybe even some wood products.

Using the mill to make a quick, clean cut, or facing a part off is something I envision frequently doing. Setting up a pennant with a dial on it would likely be the best way to accomplish this..... But I'm on a pretty tight budget and would like to phase in these expenses over time.....

Thinking ahead, however, where do these COT (commercial off the shelf) pennants wire into? The BOB, or do they input to the PC?

I'm the guy who's going to start out hooking up his motors to the factory ACME screws. I appreciate that there are better ways to do things... and I hope to get there some day. It's just going to take me a while.

I'm the guy who's going to start out hooking up his motors to the factory ACME screws. I appreciate that there are better ways to do things... and I hope to get there some day. It's just going to take me a while.

Nothing wrong with experimenting, and don't let anyone tell you that you can't whether it's a good idea or not. It's all a part of the learning experience. Some people just don't like it when ideas are punted around that challenge their own.

The point where someone believes they have all the answers, and no one else's are viable doesn't prove to me that they are smart, just smug.

Good luck on your build.

Nothing wrong with experimenting, and don't let anyone tell you that you can't whether it's a good idea or not. It's all a part of the learning experience. Some people just don't like it when ideas are punted around that challenge their own.

The point where someone believes they have all the answers, and no one else's are viable doesn't prove to me that they are smart, just smug.

Good luck on your build.

Smug ? Possibly. One of the great thing about building a machine is there is no one way. Never said there was. Offered an opinion to be taken or rejected at op's option.

Two more possible options if you want to retain manual movement
1) Do it old school by retaining dials
2) Linear type scales like a digital caliper. Read directly or with some DRO remote display.

Btw/ the link provided earlier was just to show another example of a lower powered acme Z conversion.

thankyou every one for being kind and not flaming the new guy.

my disclamer is 1. I'm not a machinist and 2. I don't pretend to be one

My interest in manual control is based on my experience with a CNC table router. Transit and Jog run off of a keyboard, imho, suck! And I have had many times wanted to just cut a quick part on the router and didn't want to fool around drafting the geometry in Auto-CAD, crunching the g-codes in Bob-CAM, and then running the file..... just to put a dado into a part. At work, this is compounded by the fact that I have to run back and forth 100 yds between two buildings to get this done.

I am hoping to use the X3 for a diverse range of HOBBY related projects.... cutting mostly aluminum, brass, and hard plastics like HDPE, ABS and UHMW, and maybe even some wood products.

Using the mill to make a quick, clean cut, or facing a part off is something I envision frequently doing. Setting up a pennant with a dial on it would likely be the best way to accomplish this..... But I'm on a pretty tight budget and would like to phase in these expenses over time.....

Thinking ahead, however, where do these COT (commercial off the shelf) pennants wire into? The BOB, or do they input to the PC?

I'm the guy who's going to start out hooking up his motors to the factory ACME screws. I appreciate that there are better ways to do things... and I hope to get there some day. It's just going to take me a while.

You seem to be unaware of MDI. MDI allows you to simply type in G-code, line by line, and it executes immediately. So, you can easily do anything you can do with manual, only FAR more accurately. No need to draft anything. You simply type in the same moves you'd make if you were turning the knobs by hand. You'll get a better result, faster. And, if it's something you're doing more than once, you can record the moves as you type them in, and for the next piece just re-run them, without having to type anything.

99% of people first getting into CNC seem to REALLY feel it's important to maintain manual control, but only about 1% actually use the capability, once they actually start using the machine, and understanding that they now have a much better way of doing it. And, handwheels on a CNC machine are not only dangerous, but throw off the balance, and limit rapid rates, due to the vibration they induce.

Regards,
Ray L.

Smug ? Possibly. One of the great thing about building a machine is there is no one way. Never said there was. Offered an opinion to be taken or rejected at op's option.

Two more possible options if you want to retain manual movement
1) Do it old school by retaining dials
2) Linear type scales like a digital caliper. Read directly or with some DRO remote display.

Btw/ the link provided earlier was just to show another example of a lower powered acme Z conversion.


I wasn't actually trying to single you out, but rather casting a broad net. Offering advice is really all in how you word it. You could offer direct criticism of an idea someone has, or you could for example say something like” I thought about using the existing screws that came with the machine, but they are very unreliable to stay adjusted, and that is why I think ballscrews are best".

It’s like if you’re a manager in a department store and you are trying to direct people under you on how you want the stock put up. You could directly tell someone the way they put up the stock is wrong and possible hurt their feelings, or you could use a little social engineering and say “ I think it would look better if it was done this way…..”.

You seem to be unaware of MDI. MDI allows you to simply type in G-code, line by line, and it executes immediately. So, you can easily do anything you can do with manual, only FAR more accurately. No need to draft anything. You simply type in the same moves you'd make if you were turning the knobs by hand. You'll get a better result, faster. And, if it's something you're doing more than once, you can record the moves as you type them in, and for the next piece just re-run them, without having to type anything.

99% of people first getting into CNC seem to REALLY feel it's important to maintain manual control, but only about 1% actually use the capability, once they actually start using the machine, and understanding that they now have a much better way of doing it. And, handwheels on a CNC machine are not only dangerous, but throw off the balance, and limit rapid rates, due to the vibration they induce.

Regards,
Ray L.

Geez Kabibble, That sounds just dreadful. It's a good thing my hand wheels are removable.

Ok instead of a flame war there are matches flying around :p

Your future MPG pendant, depending on model and type, can hook into either the BOB, utilizing parallel port(s) pins (yes, you may need to add a second or even third port to handle extended inputs and outputs) or USB - there are a number of people (on the EMC mailing list at least) using those cheap USB gamepads (or joypads - depends on terminology you use and the model/style you get - they run anywhere from $9 - $25) which can handle many of the tasks of the MPG pendant - about the only thing I know you'll definitely lose is if you get a dial type MPG which has detents for each step and you're not reading the position on screen rather counting the clicks of the wheel. You can still get the same function with the pad, just each step takes a keypress in effect. The number of buttons on those pads can be quite numerous allowing you to select a myriad of step resolutions on the fly and moving each axis with the joysticks or "D-pad".

So in short - the answer is your future pendant can be hooked up a variety of different ways depending on what you buy and how you choose to integrate it.

MDI allows you to simply type in G-code, line by line, and it executes immediately.

Sounds like the command mode on our DOS based CNC Controller.

I'm the only guy in the office that can spit out G-Codes on the fly in command mode (crimany, it's just ordinate geometry). But just because I can do it, doesn't mean I like to.

I'm also the only engineer in the office that our maintenance guys will let work on their manual knee mill, and on some of the projects that I've cut with it, I found cranking around the table to be quick and intuitive (at least once you internalize the hand wheel directions).

Himy's likely right though and I'll wind up being one of the 99% that sets up for manual with the hand wheels and then never uses them.

At this point, I'm over analyzing the project. Need to get the mill on site and roll up my sleeves. Many things will become apparent at that stage.

Thanks for bearing with my newby questions in the mean time.

We have a Pennant (all push button, no dials) with an LCD display on our Data Tech. M3 sample table. It's a BIG table, on which we cut 88" x 108" sheets of corrugated, and the pennant is handy as you walk around blocking off vacuum table leaks.

So in keeping with the KISS plug and play concept, I ordered a G540 today, while they still have the special price on their custom run overstock.... $225.

My plan is to run all three axis with the Keling KL23H284-35-4B 387 oz-in steppers, and to set up the Z-axis similar to how CAD Monkey has done, with ~2-1/2 : 1 mechanical advantage. I'm willing to live with the slower Z speeds, in favor of using the "no brainer" G540.

You COULD use the 48V 6.3A 640 oz KL34H280-45-8A with the G540, but detuning it from 6.3A to 3.5A would leave you with only 355 oz of torque. So that is not really an option.

ANOTHER option might be to use the 75V 382 oz KL23H2100-30-4B on the Z axis. It's 3/8 inch shaft might be more apt to take the stress of the heavy head load, though it would not run as fast as the 387.

At any rate, you should gear a N23 one to one or no more than 2:1 with the acme screws.

CR.

Thanks again CR,

Looks like it's 387 oz. NEMA 23's all around.....

Don't know why I second guessed my plan... to much info. bouncing around in my head.... looksl like you really meant it when you posted on another thread that there are no NEMA 34 motors that work well with the G540.

.... looksl like you really meant it when you posted on another thread that there are no NEMA 34 motors that work well with the G540.

Hopefully that is just for now.

A possible short term solution would be to find an 8 wire 4.5A 1200 ounce Nema 34 with inductance that allows BV of 48V. Then wire it 1/2 coil and with detuning down to 3.5A it will end up about 640 oz in of torque.

So far, I havn't found THIS either though.

CR.

a little progress made....

Ordered a vise, granite slab, thin paralles set and R8 collet set from Enco yesterday.

I checked stock status on the motors at Keling and he has them back in stock now, so I figured I would get them while the gettin' is good.

My co-worker is an electronics wiz who builds computers as a hobby and has expressed an interest in helping me. He came in today and said he's building a new computer for a guy and is getting a loaner PC back, which he has no need of. So get this.... he wants to donate his PC to the cause!

So within a week I should have....

Gecko 540
three 387 oz. NEMA 23 stepper motors
the power supply from the recycled Anaheim Automation driver pack.
and a PC

I've even got a nice little cart that came with our Data Tech. M3 that we scrapped when we set up that manufacturing cell with a desk at their work station.

so if I can scrounge up a monitor.... we could be having some serious fun!

quick question....

should the 120 v a.c. feed to the dc power supply be plugged into a UPS, along with the PC?

just to keep the system going long enough to hit the e-stop, before the spindle completely stalls?

or would that just be a waste?

Capital beginning. Used CRT monitors are available everywhere cheap--Even free in curbside pickup--Due to flat screen upgrading.

CR.

quick question....

should the 120 v a.c. feed to the dc power supply be plugged into a UPS, along with the PC?

just to keep the system going long enough to hit the e-stop, before the spindle completely stalls?

or would that just be a waste?

Uh! Lets see. Power fails. Spindle stops, stepper motor motion stops, computer stops. No downside except part may be stopped in middle and may or may not be restartable from that position--May lose that part, but end mill probably ok and no crash.

It would have to be a whopping UPS to allow everything to run until part is completed. So either whopping big or none I would say.

CR.

Used CRT monitors are available everywhere cheap

I think I dumped two 14" ones last year after I built my new PC :(

time to search the attic, as I also had a 19" giant beast that I doubt I tossed.

I'm sure I'll be able to dig something up

need to get serious about cleaning out some space in the basement.

Given that I use Solid Works, Auto-CAD and BobCAD/CAM at work daily, would I really need Mach 3?

Any recommendations for a share ware controller app.?

I know CAD Monkeys going to chime in with a plug for EMC ;) , which I am very interested in. But with everything else going on, figuring out how to get going in Linux seems like an unwarranted complication. :drowning:

I think I dumped two 14" ones last year after I built my new PC :(

time to search the attic, as I also had a 19" giant beast that I doubt I tossed.

I'm sure I'll be able to dig something up

need to get serious about cleaning out some space in the basement.

Given that I use Solid Works, Auto-CAD and BobCAD/CAM at work daily, would I really need Mach 3?

Any recommendations for a share ware controller app.?

I know CAD Monkeys going to chime in with a plug for EMC, which I am very interested in. But with everything else going on, figuring out how to get going in Linux seems like an unwarranted complication.
Mach 3 isn't for designing or G code generation, it's for machine control. It works with the others you've listed, not instead of.

Mach 3 isn't for designing or G code generation, it's for machine control.

from my limited reading about it, it looked like it's a controller + lot's of other goodies.

Isn't it bundled with LazyCAM?

My point is that since I'll cook all my G-codes in BobCAM, is there a super scaled down controller out there I can run for free?

How's the Mach trial work?

unlimited use with some features disabled? that might work for me.

or does it turn into a pumpkin after the demo expires.

It certainly appears to be a steal of a deal, but even a measly $150 is going to hurt right now. I'd rather use that money to spring for ball screws on X & Y.

The demo Mach3 has NO features disabled. Only downside is 500 lines of code limit and only 25K computer pulse rate.

If you run Linux, emc2 is free.

You MUST have SOME kind of machine control software in addition to CAD/CAM. You could manually program G Code in Mach3 without ANY CAD/CAM and still make parts. Not so with only CAD/CAM software.

CR.

Only downside is 500 lines of code limit and only 25K computer pulse rate

O.K. so the Gecko 205s in my G540 have a 300 KHz pulse rate, but Mach will put a software cap on that of 25 Khz. If I was running a licensed seat of Mach, would I have to cap the pulse rate to limit my transit speeds anyways? If so, roughly what pulse rate would translate to ~50 ipm.....

let's see if I can nuke it out ...

motors have 200 step/rev, say I microstep to 10. That's 2,000 steps per rev. But the lead screw is 10 tpi, so it takes ten revs to get an inch. So I need 20,000 steps to get an inch. If I want to run at say, 50 ipm, then I need 1,000,000 steps /min. or 16,667 steps per sec. which is 16.7 Khz pulse rate.

so to work that backwards.... 25KHz limit would give me a max transit of 75 ipm.

did I get that right?

I could probably live with that....

500 lines of code could be an issue...... but I could tackle that bridge when I come to it.

I'm not trying to avoid cost, just to defer them so my start up doesn't break the bank.

Any other shareware controler options out there?

and ...

Can Mach support a tangential knife tool run on a gantry table router set up?

O.K. so the Gecko 205s in my G540 have a 300 KHz pulse rate, but Mach will put a software cap on that of 25 Khz. If I was running a licensed seat of Mach, would I have to cap the pulse rate to limit my transit speeds anyways? If so, roughly what pulse rate would translate to ~50 ipm.....

let's see if I can nuke it out ...

motors have 200 step/rev, say I microstep to 10. That's 2,000 steps per rev. But the lead screw is 10 tpi, so it takes ten revs to get an inch. So I need 20,000 steps to get an inch. If I want to run at say, 50 ipm, then I need 1,000,000 steps /min. or 16,667 steps per sec. which is 16.7 Khz pulse rate.

so to work that backwards.... 25KHz limit would give me a max transit of 75 ipm.

did I get that right?

I could probably live with that....

500 lines of code could be an issue...... but I could tackle that bridge when I come to it.

I'm not trying to avoid cost, just to defer them so my start up doesn't break the bank.

Any other shareware controler options out there?

and ...

Can Mach support a tangential knife tool run on a gantry table router set up?

Your calculations are correct. You might want to look at TurboCNC. I believe the "trial" version has no limits. But, it runs under DOS, not Windows. It does not have anywherre near the functionality of Mach (which can be either good or bad....).

Regards,
Ray L.

The only other controller software I've used besides Mach is KCam from Kellyware. (http://www.kellyware.com/kcam/index.htm)
Older but worked.

Mach3 is really good software, as anyone on here will attest to. but 500 lines of code will go by really fast if your making many moves that arent a straight line, or an interpreted curve.

especially if your gonna do any kind of 3d parts, i had a (what i thought was simple) little thing to make a parabolic soap dish, running full 3d movements (z level roughing and constant offset finishing) and it was well into the 20k lines count.

Could someone please comment as to whether or not this power supply:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEBIDX:IT&item=350162962855
48V DC 7.3A

Would be suitable to run three of these stepper motors:
KL23H284-35-4B (1/4” Dual shaft with a flat) 387 oz-in

via. a G540?

My salvage power supply may no longer be available, so I'm looking into buying one.

3.5 + 3.5 +3.5 = 10.5A total. 10.5 x .6 = 6.3A required to run three motors, with a 1A safety factor. The 7.3A PSU should work fine. On a Mill with a fourth axis and 4 387s, it would probably run 4--because you wouldn't run more than 3 at a time. Now on a router wirh slaved X axis and 4 387s, you would need at least 8.4A.

CR.

seeing how small the G540 and the regulated pwr supply are, I'm wondering if I wont be able to mount them right inside of the back cover of the mill.

Any body ever seen it done?

got a picture?

I have to say, that little G540 is an amazing little feet of engineering. They sure pack a lot into that tiny little box.

If you can insulate it and seal up the seams of the compartment (mine had room enough for a chip to find it's way behind the motor control board, didn't damage it but...) it should be ok. Keep in mind accessibility. It's kind of awkward to get at the back of the column if it's on a stand without casters against a wall. Personally I got LUCKY and got a great deal (free) on a large industrial grade case for my whole control and PC and no electronics are on the mill itself. Any chance you could fit it into the case of the PC?

And yes - I saw the EMC comment earlier :) I won't extoll its virtues and sing its praises to the heavens, but at least download and burn the ISO and try the LiveCD. The Linux GUIs aren't much different from Windows - not much learning, if any, if the computer is dedicated to the machine. All you've got to lose is an hour or so and a blank CD (maybe a while longer if you've got a slow connection). :) There, my Open Source preaching is done. :)

Got my 387 oz. Keling NEMA 23s today. The reality of the scale of the mill set in when I opened the box, as they certainly are tiny.

my Open Source preaching is done.

You can keep on preaching it.... and I just might be checking it out and hitting you up for help.

For now I need to keep the project simple.... and that means plug and play. So I'll start off with the Mach 3 demo and take it from there.

I priced out Ball screws and Nuts today, and it looks like it will run me $200 for a basic rolled screw set up with cheap nuts.

I need to get the mill on site and set up before I bite at that one though.

Chow....

Got my 387 oz. Keling NEMA 23s today. The reality of the scale of the mill set in when I opened the box, as they certainly are tiny.

Uh, have you SEEN an X3? it's far from tiny.

CR.

Uh, have you SEEN an X3? it's far from tiny.

Ya, I've seen the mill.... (but not one that is converted).

what I meant was that the motors seem tiny.

for some reason, I thought they would be closer to the size of the Pac. Sci. motors on our CNC router..... which are the older, cylindrical shape and are quite a bit larger.

None the less, the proof is in the putting and @ 387 oz-in, these are certainly torquey little buggers.

Well, further study has me thinking that I should plop down the extra ~$200 on rolled ball screws and ball nuts.

and now that I have first hand knowledge as to the size and weight fo the 387 oz Nema 23s I'm using, I'm stearing towards motor mounts that look like this.....
75966

Now following Dick Stephen's plan over at the Model Engineers Workshop, he used rolled 12mm dia. 2mm pitch ball screws....

The nice advantage of this is that both the existing ACME threaded bronze nut blocks can be bored out to accept the 12mm ball nuts.

I especially like this, as it keeps the factory taper pins in the equation for mounting the nut blocks.

If metric hardware is two pricey, perhaps I could pull off the same trick with 1/2".

I'm seeing that both CNC Fusion and CAD Monkey have used 5/8" hardware.

But again, this machine is truely for hobby use and not production work.

Any feedback on this plan would be appreciated.

Matt

Matt;

As you continue to research you will find that the 5/8" ballscrew stock is by far the cheapest... Smaller sizes start costing double and triple.

I would just grab Greg's (aka CadMonkey) print set and start digging in the scrap piles for suitable chunks of material.

Also Double ++ on using the Nook XPR screw stock.

I'll have to look in my Nook catalog when I get home late tonight and see if I am remembering correctly - I think metric screws are measured by their root diameter, whereas english by their nominal OD - thus a 12mm and a 5/8 are roughly the same (the root of the 5/8 screw stock is right around 1/2" thus I ground my journals to 10mm for 1mm shoulders at the bearings). I could be wrong (it happens a bit) so don't take that as gospel.

EDIT I was wrong - a 12mm x 2 Nook has a 10.6mm root diam, 12mm x 4 = 9.8mm root diameter. And the root diameter on the Nook 631's is .500"

Sorry - at least I verify my facts...
/EDIT

Well I painted like a busy beaver tonight.... and have a friend coming over to help paint tomorrow...... and that means..... I'll have fullfilled (mostly) my honey-do pre-req. and can order the mill on Friday :)

Can anyone tell me if Grizzly ships their X3 mill assembled? Or does it come with the head removed?

If assembled, is the mill sufficiently secured to the base of the crate that I can tilt the crate without having the mill topple over inside the crate?

The reason I ask is because I have to get the sucker down into my basement, via. the bulkhead steps. If I put a pair of 2x8's on the steps to serve as skids, I can strap the crate and lower it down with my tractor bucket (give me hydraulics or give me death). But this will require leaning the crate over quite a bit.

Hmmmm....

mine was held by two 1/4" bolts... :confused:

it held good - but crate was never stressed - it was always supported on a forklift.

It's a pretty sturdy crate. The mill is securely bolted to the base. Make sure your strap is between the middle and the base as that is strongest point of crate. You COULD remove top and sides of crate and leave mill on skid.

You also could easily disassemble mill into 4 carryable segments: Base, table/saddle, head and column. Read up on disassembly here:

http://www.arceurotrade.co.uk/projects/prepguides/X3%20Mill%20Preparation%20Guide.pdf

The mill will come on an 18 wheeler. It will need wide enough streets to be able to get to you or you will have to meet driver with your tractor. I had to do this. The crate fit into the bucket of my neighbor's Kubota.

Grizzly's approx $100 shipping fee sure beats Novakon's $700 or Syil's $400. This heinous shipping differential is ONE of the reasons that I did not BUY the Syil SX3 and chose instead to roll my own.

CR.

yea, mine came all in one big chunk, all put together that is. you can try and do the skid thing, but that sounds like the riskier way to do it..

if you can, i would pull it apart and carry it. your gonna wanna take it apart to clean it up anyway, and if your gonna start your conversion right away, then you might as well have it apart...

I bought my drill press from Grizzly a couple of years back so I know the drill wrt. truck shipment.....

I pitty the poor truck driver that tries to come down our skinny 800' gravel driveway in the woods. Even the propane guy got stuck this winter....

I've got a pretty good situation at work. I just have it delivered to the company and have the guys drop it in the back of my truck with a fork lift. I'll have to pull the truck cap for a few days....but that's not really an issue. I made quick change forks for my little tractor, so my thought was to rig the crate down the bulkhead with chains and straps, etc... Tipping the crate 30 degrees would put the hardware mounting the crate to the base to the test though, that's why I inquired about it.

Then again.....

We have an area (old garage attached to the little house turned office) that we use to store customer samples, maybe I'll plop the crate in their and disassemble the mill and take it home in pieces. Have to check with da boss on that one though. This would probably be easier, but I don't like involving to many people at work in my personal business.

Decisions, decisions....

Grizzly paint chips really easily. If you disassemble at work--Wrap everything up in towels to protect it. Maybe you could clean off the red grease there too.

CR.

thanks for the heads up guys....

we'll keep you posted...