# CNC Mill Conversion Questions.



## Eddyde

Hi All,
I am planning to convert a Milling Machine to CNC. so far, I have read a couple of books on the subject and done a lot of internet research. I am leaning towards a new bench type, SIEG or Rong Fu type mill since getting a Bridgeport into the basement seems a bit too daunting. However, I do love vintage machines and might go that route if the right machine comes along.

I have a couple of questions and would appreciate any help:

1. Has anyone used the ball-screws, stepper/servo motors, etc. from China? The pricing is very attractive, I know the big name gear is better but is it really worth the exponential investment?

2. Can I use the linear encoders from a DRO in place of the rotary encoders on servo motors? It seems such an arrangement would compensate for any backlash in the system and be more accurate. I know some of the very high end industrial machines use this method but I don't see much info on DIY versions.

Many Thanks

Eddy


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## Karl_T

Eddyde said:


> ...
> 
> 2. Can I use the linear encoders from a DRO in place of the rotary encoders on servo motors? It seems such an arrangement would compensate for any backlash in the system and be more accurate. I know some of the very high end industrial machines use this method but I don't see much info on DIY versions.
> 
> Many Thanks
> 
> Eddy



Maybe, some of them are compatible. heidenhine (SP???) for sure works. They need to put out a quadrature encoder signal. IMHO, this is for high end machines - you need a really tight machine or the servo will hunt all over and not be stable.

Just my 2 cents, if you're going with Asian equipment, stay with steppers and go Mach control. Low cost, makes a fair hobby machine.

If you want something faster and more rigid, do what it takes to find a CNC machine with a dead control. They are out there, may have to travel. Bridgeport series I and II, Excello, Shizouka, Heidenhein (SP???) Wells, Supermax are just a few names. Then go with DC servos and LinuxCNC for a control with position feedback.

I'll just mention Camsoft is higher end yet. I own and have installed many of these systems.

Karl


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## JimDawson

Eddyde said:


> Hi All,
> I am planning to convert a Milling Machine to CNC. so far, I have read a couple of books on the subject and done a lot of internet research. I am leaning towards a new bench type, SIEG or Rong Fu type mill since getting a Bridgeport into the basement seems a bit too daunting. However, I do love vintage machines and might go that route if the right machine comes along.
> 
> I have a couple of questions and would appreciate any help:
> 
> 1. Has anyone used the ball-screws, stepper/servo motors, etc. from China? The pricing is very attractive, I know the big name gear is better but is it really worth the exponential investment?
> 
> 2. Can I use the linear encoders from a DRO in place of the rotary encoders on servo motors? It seems such an arrangement would compensate for any backlash in the system and be more accurate. I know some of the very high end industrial machines use this method but I don't see much info on DIY versions.
> 
> Many Thanks
> 
> Eddy




I'm not sure about the hardware from China, the servo systems seem to be kind of new on the market so there is not much history yet, I have not heard anything good or bad.  The stepper motors are a pretty mature product and I have heard no complaints.  The stepper drivers do lack some of the features of some of the better American hardware.  Ball screws?, probably OK, but who knows.

There is no reason that you could not use linear scales in place of the encoder, as long as the controller will accept the output from the scale.  If the scale outputs a standard quadrature output, then you should be good to go.  It depends on what motion controller you choose to use.  You are correct, doing it this way compensates for any backlash and any leadscrew error.  I use 1 micron magnetic scales on my machine.

Depending on what stepper drive/motion control system you decide to use, it is possible to close the loop on the stepper system and also operate the stepper just like a servo in velocity mode, rather than step & direction.


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## JimDawson

Karl_T said:


> Maybe, some of them are compatible. heidenhine (SP???) for sure works. They need to put out a quadrature encoder signal. IMHO, this is for high end machines - you need a really tight machine or the servo will hunt all over and not be stable.
> Karl



I know that Anilam Crusader M controllers will take a 10 micron quadrature input also, not sure about any others.

As long as it is possible to adjust the PID loop parameters, you should be able to tune the system so it doesn't hunt.  If you can't get to those parameters, then I would say it would be almost impossible to tune and would be unstable.  My machine holds +/- 1 count (0.000039 inches)


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## chuckorlando

Jim if you lived close by, you would have to beat me out your shop with a broom. I need a good couple days with a guy like you to wrap my brain around all this. It's like reading spanish to me, and I cant read spanish ahaha


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## JimDawson

I don't read Spanish either, but I do a pretty good job translating "Chinglish" from the user manuals.:lmao:


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## Karl_T

I'll point out a real economical way to do linear encoders:
http://www.usdigital.com/products/encoders/incremental/linear/LIN

My motion controller (Galilmc.com) allows PID tuning with one encoder and destination control with a second.  Put the linear unit as destination control. This would be the best of both worlds. Bet there are others out there with this feature.

Karl


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## JimDawson

Karl_T said:


> I'll point out a real economical way to do linear encoders:
> http://www.usdigital.com/products/encoders/incremental/linear/LIN
> 
> My motion controller (Galilmc.com) allows PID tuning with one encoder and destination control with a second.  Put the linear unit as destination control. This would be the best of both worlds. Bet there are others out there with this feature.
> 
> Karl



I use Galil products also.  You are correct, there are others that have the same features, but they cost a lot more than Galil, and are much more difficult to setup and program, and in most cases you have to buy their proprietary software to program them.  I do a lot of my Galil programming in Notepad or Excel.


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## Eddyde

Thanks for the link and the info, very helpful.


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## Gary Ayres

Good luck with the conversion.

I plan to do the same to my 626 mill next year, so will check in on this thread from time to time.


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## Eddyde

Thanks Gary,

I am now leaning towards using a closed loop stepper system, with rotary encoders on the steppers. This seems to be the newest approach and offers the best attributes of steppers and servos. The linear encoder approach seems too costly for now, as the only dual-encoder input controller/driver, I could find, is north of $2,000 USD...


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## Gary Ayres

Thanks for this. Will bear in mind what you say when I get started. 2000 bucks is too much...!


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## bladehunter

I'm kinda in the middle of a conversion (4 odd years collecting bits and money). Anyways I sent a email off Friday night to a China based ebay dealer for some ballscrews with end machining to suit my application. Within 10 minutes I had a reply and the order was completed later that night.
There's a lot of happy campers that have used Chinese ballscrews for their conversions. As long as you realise that they are what they are you should be happy. Like many have mentioned on cnczone without Chinese ballscrews many of us would still be using stock leadscrews in our conversions.
Just remember try not to chase accuracy from your ballscrews that your hobby mill can't reach. Don't discount one of the G0704/BF20 mills, I'm really happy with mine.
Once I get my screws I could let you know what I think of them if you like.

Rob.


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## Karl_T

Eddyde said:


> Thanks Gary,
> 
> I am now leaning towards using a closed loop stepper system, with rotary encoders on the steppers. This seems to be the newest approach and offers the best attributes of steppers and servos. ..



This would be a good goal. Might i suggest you walk before you run and just get the plane Jane stepper system running first. Then do an upgrade.

BTW, I'd also suggest you spend time lurking (or even posting) on CNCzone.com. maybe not quite as helpful folks as here, but CNC is all they do and there's a LOT of knowledge there.

Karl


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## bladehunter

+1 for cnczone. A wealth of info there.

Regarding the X3, here are some reproduced articles from "Model Engineers' Workshop". With permission from MEW.

http://www.arceurotrade.co.uk/projects/X3-CNC/X3cncIndex.html


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## TomS

bladehunter said:


> I'm kinda in the middle of a conversion (4 odd years collecting bits and money). Anyways I sent a email off Friday night to a China based ebay dealer for some ballscrews with end machining to suit my application. Within 10 minutes I had a reply and the order was completed later that night.
> There's a lot of happy campers that have used Chinese ballscrews for their conversions. As long as you realise that they are what they are you should be happy. Like many have mentioned on cnczone without Chinese ballscrews many of us would still be using stock leadscrews in our conversions.
> Just remember try not to chase accuracy from your ballscrews that your hobby mill can't reach. Don't discount one of the G0704/BF20 mills, I'm really happy with mine.
> Once I get my screws I could let you know what I think of them if you like.
> 
> Rob.



I too am in the middle of a CNC conversion.  Bought my ball screws and nuts on eBay from a Chinese supplier as well (Linear Motion Bearings).  Could be the same vendor you used.  Service and price was excellent.  I received the screws and nuts and visually they looked good.  The vendor sent a BK style housing instead of an FK style.  Sent a note and within minutes received a response that the FK will be sent next day.  Didn't ask for the BK housing to be returned.

Still building the mounting brackets so I haven't had a chance to check backlash yet.  

Tom S


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## jumps4

I have converted 4 mills and 2 lathes with all Chinese parts. from Sherline to my zx45 mill with no real problems. most of the steppers you buy from US sellers are made in china and relabeled. the thrust bearings that come with the ballscrews have to be shimmed to get the proper preload but work good once done. I have purchased stepper motors from 170oz/in to 4200oz/in and have never got a bad one. My zx45 has shown no wear in 2 years of steady use and none of my controllers give any problems. I do use large enclosure fans and filter the intake air though. For the money at $3800.00 including the new zx45 mill and 6" rotory table for the forth axis you can't beat it.
steve


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## Eddyde

Gary Ayres said:


> Thanks for this. Will bear in mind what you say when I get started. 2000 bucks is too much...!





Update:
One of the members wrote me privately and enlightened me to Galil controllers selling on ebay for around $500 for a 4 axis board that will accept dual encoder inputs! So the linear encoder isn't out of the question.


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## Eddyde

jumps4 said:


> I have converted 4 mills and 2 lathes with all Chinese parts. from Sherline to my zx45 mill with no real problems. most of the steppers you buy from US sellers are made in china and relabeled. the thrust bearings that come with the ballscrews have to be shimmed to get the proper preload but work good once done. I have purchased stepper motors from 170oz/in to 4200oz/in and have never got a bad one. My zx45 has shown no wear in 2 years of steady use and none of my controllers give any problems. I do use large enclosure fans and filter the intake air though. For the money at $3800.00 including the new zx45 mill and 6" rotory table for the forth axis you can't beat it.
> steve



Thanks, I will most likely go with the Chinese or Taiwanese ball screws and motors and go with US made controllers/drivers.


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## Eddyde

Karl_T said:


> This would be a good goal. Might i suggest you walk before you run and just get the plane Jane stepper system running first. Then do an upgrade.
> 
> BTW, I'd also suggest you spend time lurking (or even posting) on CNCzone.com. maybe not quite as helpful folks as here, but CNC is all they do and there's a LOT of knowledge there.
> 
> Karl




Thanks Karl,

I hear you on keeping it simpler in the beginning but it would mean repurchasing the drivers and motors or having to add encoders to the motors in the future. I'd rather go all-in and get it done. I know the learning curve will be steeper but to me, the challenge is the fun.

Yes I have been lurking the CNC Zone, lots of useful info there.


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## bladehunter

Yep that's the one Tom, guy to contact is Chai. Linearmotionbearings have been on ebay for a while (could be the longest) almost everyone seems happy with his service.


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## jumps4

Eddyde said:


> Thanks Gary,
> 
> I am now leaning towards using a closed loop stepper system, with rotary encoders on the steppers. This seems to be the newest approach and offers the best attributes of steppers and servos. The linear encoder approach seems too costly for now, as the only dual-encoder input controller/driver, I could find, is north of $2,000 USD...



rotary encoders on the stepper motors will not compensate for backlash, they will only pick up missed steps from the motor. the backlash in the table movement will not be seen by the encoder because the movement is all after the motors output shaft. even placing them on the end of the ballscrew will not reflect true table movement. I started out chasing the perfect setup and it is really not feasible on these types of machines. after rethinking what I will be making and the fact not everything on a part has to be in perfect specs just certain points. I went with the basic setup to make the part leaving the really precision points undersize and then come back with measurement's to locate and machine those areas. any machine has to be learned by the operator and they all have hi and low points. I was driving myself nuts chasing perfection when It wasn't really required for one off or short run hobby machining.
steve


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## Eddyde

jumps4 said:


> rotary encoders on the stepper motors will not compensate for backlash, they will only pick up missed steps from the motor. the backlash in the table movement will not be seen by the encoder because the movement is all after the motors output shaft. even placing them on the end of the ballscrew will not reflect true table movement. I started out chasing the perfect setup and it is really not feasible on these types of machines. after rethinking what I will be making and the fact not everything on a part has to be in perfect specs just certain points. I went with the basic setup to make the part leaving the really precision points undersize and then come back with measurement's to locate and machine those areas. any machine has to be learned by the operator and they all have hi and low points. I was driving myself nuts chasing perfection when It wasn't really required for one off or short run hobby machining.
> steve




Thanks Steve,

I am aware that the rotary encoders won't tell the true table position, that's why I was initially thinking of using linear encoders instead. However, it seems in order to do a successful setup using linear encoders, they must be used in conjunction with rotary encoders, as a second encoder input. My first investigation into "dual encoder input controllers" could only find very expensive options "north of $2,000". Fortunately a gracious member wrote me privately and turned me on to some Galil controllers on ebay that have dual encoder capability and can be had for south of $1000, So I think will invest in one of these controllers. For now, I will go with the steppers & rotary encoders then add the linear encoders later on, as I will have the capability. 
Let's just say I am an "accuracy freak" 
Cheers 
Eddy


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## JimDawson

I agree with Steve.  An encoder on a lead screw is a useless endeavor in either a stepper or servo system, unless you have a high end machine with double ball nuts, and high precision ball screws.  It will pick up lost steps, but that's about it.  The positioning will be pretty close, but the backlash and lead screw error will not be compensated for.  IMHO the measuring feeback device needs to be on the load, in this case the table or the quill.  In the hobby shop, an occasional Oh S&*^ moment is probably acceptable, but if not, then a bit more hardware is needed.


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## JimDawson

Eddyde said:


> ........
> However, it seems in order to do a successful setup using linear encoders, they must be used in conjunction with rotary encoders, as a second encoder input. ........
> Let's just say I am an "accuracy freak"
> Cheers
> Eddy



I have to disagree that theory.  If you have a linear encoder (any kind of a linear measuring device) attached to the load (table), and that will output a quadrature signal, it can and should be used as the primary encoder.  That will achieve the maximum accuracy.  The secondary encoder is not needed unless the application absolutely must not fail.  Think aerospace and military applications.

My mill holds a 0.0001 repeatable position, not that my parts come out that close, because there are other factors at work also.  But actual tolerance is generally in the range of +/- 0.0005 if I don't get too greedy with the cut.


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## Eddyde

JimDawson said:


> I have to disagree that theory.  If you have a linear encoder (any kind of a linear measuring device) attached to the load (table), and that will output a quadrature signal, it can and should be used as the primary encoder.  That will achieve the maximum accuracy.  The secondary encoder is not needed unless the application absolutely must not fail.  Think aerospace and military applications.
> 
> My mill holds a 0.0001 repeatable position, not that my parts come out that close, because there are other factors at work also.  But actual tolerance is generally in the range of +/- 0.0005 if I don't get too greedy with the cut.



Okay maybe I have it wrong, I was looking into a "closed loop stepper drive" like this:
http://www.leadshine.com/category.aspx?type=products&category=easy-servo-products
I thought it would be necessary to use a "dual encoder input  controller" such as the Galil, to make it work with linear encoders?


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## JimDawson

Eddyde said:


> Okay maybe I have it wrong, I was looking into a "closed loop stepper drive" like this:
> http://www.leadshine.com/category.aspx?type=products&category=easy-servo-products
> I thought it would be necessary to use a "dual encoder input  controller" such as the Galil, to make it work with linear encoders?




I read through the product specs, they are closing the loop with the encoder on the motor.  This will work fine in most applications, it just does not account for lead screw errors. It will keep the system from loosing pulses, and is probably adequate for the home machine shop.

It looks like they have ''smart'' drives that will insure that the motors reach the commanded position by reading the encoder feeback.  Not a bad system.  I have never seen these before.  I need to look into this further.

I can see where the confusion is.  In this case, it would really not be necessary to have both an encoder on the motor and an encoder on the load.


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## Eddyde

JimDawson said:


> I read through the product specs, they are closing the loop with the encoder on the motor.  This will work fine in most applications, it just does not account for lead screw errors. It will keep the system from loosing pulses, and is probably adequate for the home machine shop.
> 
> It looks like they have ''smart'' drives that will insure that the motors reach the commanded position by reading the encoder feeback.  Not a bad system.  I have never seen these before.  I need to look into this further.
> 
> I can see where the confusion is.  In this case, it would really not be necessary to have both an encoder on the motor and an encoder on the load.



Okay so if I don't need encoders on the motor and on the load then why do I need the Galil controller that accepts dual encoder inputs? Or would that be necessary only if i used servos?


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## JimDawson

Eddyde said:


> Okay so if I don't need encoders on the motor and on the load then why do I need the Galil controller that accepts dual encoder inputs? Or would that be necessary only if i used servos?



Well, actually you don't need dual encoder inputs, in most cases.  If you were to use a Galil controller to operate stepper motors and were using it in step and direction mode, then you would need the Aux encoder for position feedback if you want to close the loop.  This is because Galil uses the main encoder counter to generate the step output.

You can have the encoder feedback generated from an encoder on the leadscrew, motor, or the load.

Dual encoders are not normally needed on servo systems, as long as the system is tight.  If the feedback is from the load it's self, then really only one encoder is required.


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## bladehunter

Regarding Chai's ballscrews.

Got them yesterday (Tuesday), screws machined to my specs, nut ground as per drawing, ground section finished as per the rest of the nut, looks like an off the shelf item.

Cost was US $120.00 for parts and $49.00 shipping,great value for a hobby machine I reckon. Doubt very much if I could get just one screw for that amount locally. Just prepping the machine for installation, as I figure it'd be a good Father\Son thing.

I'll report back after the weekend regarding operation.


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## TomS

bladehunter said:


> Regarding Chai's ballscrews.
> 
> Got them yesterday (Tuesday), screws machined to my specs, nut ground as per drawing, ground section finished as per the rest of the nut, looks like an off the shelf item.
> 
> Cost was US $120.00 for parts and $49.00 shipping,great value for a hobby machine I reckon. Doubt very much if I could get just one screw for that amount locally. Just prepping the machine for installation, as I figure it'd be a good Father\Son thing.
> 
> I'll report back after the weekend regarding operation.



I had the same experience.  Bought the ball screw/nut package (X, Y, Z screws and nuts, 2 BK12 housings, 1 BF12 housing, and 1 FK15 housing) for $196.00 including shipping.  I made a mistake on the X axis screw length and ordered another for $59.00 including shipping.  I have no affiliation with Linear Motion Bearings but when I get exceptional service at a reasonable price I like to share this with others.  Chai is the guy!

Tom S


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## JimDawson

*Re: more cnc Q.*



Eddyde said:


> Hi Karl,
> I am also shopping for a pc to run my CNC mill project, this is one being considered:
> http://www.ebay.com/itm/321497867225?_trksid=p2060778.m1438.l2649&ssPageName=STRK:MEBIDX:IT
> I'm attracted to its very small size, It doesn't have a parallel port but I don't think I'll need one as I'm going to use a Galil 2240 motion controller that uses RS232 or ethernet. Am I on the right track or do you see any pitfalls I am not aware of?
> 
> Thanks
> 
> Ed





MarkStephen said:


> I'm not so sure of this one. These types on minis have a tendency to bottleneck, especially running windows. If your streaming to a caching controller, (do the Ethernet controllers cache?), this would probably not be a problem, though for modest increase in size, I would think this one mentioned before would be a better machine for the task and leave the option for parallel port intact.
> 
> Mark




That mini should work fine with a Galil controller. The Galil controller has 256 line cache.  This should be in it's own thread, we're kind of hijacking MCRIPPPer's thread.  Eddyde, if you want more information on this subject both Karl and I can help you out.


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## Eddyde

*Re: more cnc Q.*



MarkStephen said:


> I'm not so sure of this one. These types on minis have a tendency to bottleneck, especially running windows. If your streaming to a caching controller, (do the Ethernet controllers cache?), this would probably not be a problem, though for modest increase in size, I would think this one mentioned before would be a better machine for the task and leave the option for parallel port intact.
> 
> Mark



Thanks Mark, I'll verify the "caching controller". I would think it does, as the Galil is a fairly sophisticated industrial controller. The mini PC says it has been tested with various versions of Windows, including XP which is what I would be running. If I can get it to work, it is the one I would like to use. If not this one looks good as well: Dell Optiplex 745 SFF Pentium D DC 2.8GHz 4GB 160GB.


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## Eddyde

*Re: more cnc Q.*



JimDawson said:


> That mini should work fine with a Galil controller. The Galil controller has 256 line cache.  This should be in it's own thread, we're kind of hijacking MCRIPPPer's thread.  Eddyde, if you want more information on this subject both Karl and I can help you out.



Thanks Jim, I'll move the discussion Here.


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## Eddyde

_Originally Posted by *Eddyde* _
_Hi Karl,_
_I am also shopping for a pc to run my CNC mill project, this is one being considered:_
_http://www.ebay.com/itm/321497867225...%3AMEBIDX%3AIT_
_I'm attracted to its very small size, It doesn't have a parallel port but I don't think I'll need one as I'm going to use a Galil 2240 motion controller that uses RS232 or ethernet. Am I on the right track or do you see any pitfalls I am not aware of?_

_Thanks_

_Ed_




_


JimDawson said:



			That mini should work fine with a Galil controller. The Galil controller has 256 line cache. This should be in it's own thread, we're kind of hijacking
		
Click to expand...




JimDawson said:



MCRIPPPer's thread. Eddyde, if you want more information on this subject both Karl and I can help you out.

Click to expand...

_



Jim Thanks for all your help. So far, I purchased a Galil 2240 motion controller and 2900 interconnect module with cable. Now, I'll I'll buy the mini PC as it sounds like it would work. I also am trying to finalize the motor decision... I'll post some questions on that a little later.


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## Karl_T

*Re: more cnc Q.*



Eddyde said:


> Hi Karl,
> I am also shopping for a pc to run my CNC mill project, this is one being considered:
> http://www.ebay.com/itm/321497867225?_trksid=p2060778.m1438.l2649&ssPageName=STRK:MEBIDX:IT
> I'm attracted to its very small size, It doesn't have a parallel port but I don't think I'll need one as I'm going to use a Galil 2240 motion controller that uses RS232 or ethernet. Am I on the right track or do you see any pitfalls I am not aware of?
> 
> Thanks
> 
> Ed




I'll only speak for Galil cards with my control, Camsoft. The Ethernet connection does not work as well as having the card right on the computer's PCI bus. I go with the HP/Compac because its plenty big enough to take the oversize Galil cards.

Ethernet may be fine for other uses with Galil.

Karl

EDIT, my bad, i just answered without reading above. sorry to mess up this thread.

Mods can you move it?


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## JimDawson

Good call on the Galil motion controller.  Did you get the 100 pin cable with the system?  What controller software are you planning on using?

I have done 3 CNC conversions using Galil, with one in process right now.


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## Eddyde

JimDawson said:


> Good call on the Galil motion controller.  Did you get the 100 pin cable with the system?  What controller software are you planning on using?
> 
> I have done 3 CNC conversions using Galil, with one in process right now.



Yes, Thanks for suggesting Galil, once I researched their products I felt they were the best choice for the project. I do have the 100 pin cable however its 4m long and I'm planning on mounting the interconnect module right next to the motion controller. I am looking for a shorter cable on eBay, if I find one, I'll sell the long one. I'll also need a 2908 module and cable for the aux encoders, they seem a little scarce, at least for a reasonable price.
I was thinking Mach 3 but now they released Mach 4 so I'll see if that's compatible with the DMC2240.


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## Eddyde

*Re: more cnc Q.*



Karl_T said:


> I'll only speak for Galil cards with my control, Camsoft. The Ethernet connection does not work as well as having the card right on the computer's PCI bus. I go with the HP/Compac because its plenty big enough to take the oversize Galil cards.
> 
> Ethernet may be fine for other uses with Galil.
> 
> Karl



The Galil DMC-2240 that have is a stand alone controller not a PCI Bus card so I have to go with RS232, Ethernet.


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## JimDawson

Regarding Mach3 and Galil  

Here is an excerpt from my website: ( http://www.dawsoncontrols.com/millupgrade.html )

''I recently did a retrofit on a 4-axis (basically has 2 independent Z-axes) CNC router for a customer using Mach3 CNC software and stepper motors and a couple of cheap parallel interface boards (this was not my system of choice, it was dictated by the customers’ budget).  It worked pretty well except it would tend to lose pulses on turns and on the Z-axis.  I could never get it exactly right no matter what adjustments I made.  I finally tried installing a Galil Motion Control DMC-1846, 4-axis motion controller, and tried to run it on Mach3 with the Galil third party plug-in.  That was a complete disaster.  Mach3 was trying to micro-manage the very intelligent Galil card and Galil didn't like it one bit. _Disclaimer:  This is not to say that Mach3 or the Galil plugin is a bad program, I have used Mach3 successfully in other, lower speed applications with out the plugin.  It seems to work fine at slower speeds, but when the speed requirement goes up it seems to come up a bit short.''
_
Mach4 may solve the problems I had with Mach3.  What Mach3 did along with the Galil plugin is to try to operate the Galil card like a parallel breakout board, and that just overloaded the Galil buffer with hundreds of commands / second, rather than letting the Galil card actually control the motion.  All of the motion control was being done in Mach3.  The way it should work is to send a translated G-code line out to the Galil and let Galil figure out how to best execute the move, that is what is does for a living.  IMHO whoever wrote the Galil plugin for Mach3 made a tactical error in the way they approached the task.

The above problems are what prompted me to write my own controller software, which I'll give away for free to anyone that can use it.  It will only work with Galil products.

The best deal I could find on a 2908 module is $208.50, the 36 pin cable may be available from Galil, I can't find it anywhere else.  If you use closed loop steppers, you won't need the 2908 module unless you want to use the AUX encoder inputs for another purpose.

Another option is to operate the steppers in velocity mode rather than step and direction.  Then you would use the Main Encoder inputs for encoder feedback, and use the +/- 10 volt analog command signal to drive the steppers amps.  In this mode, the steppers act just like servo motors.  You do have to use stepper drives that will accept the analog input signal, normally +/- 5 volt or 0-5 volt input.  It's no problem to program everything to do this.  In a few days, I should have a couple of stepper velocity controllers that I bought for a project, I'm going to see if it's possible to run them from a Galil command signal.


----------



## Karl_T

*Re: more cnc Q.*



Eddyde said:


> The Galil DMC-2240 that have is a stand alone controller not a PCI Bus card so I have to go with RS232, Ethernet.



When you get into it, I'd like to know how Mach4 does things with Galil.

For example, when any input changes state, Galil sends a computer "interrupt" signal to the host computer. In the case of Camsoft, the host will then scan all inputs and run any code that's called out.  The simplest examples is halt motion when a limit switch is hit or just turn on the coolant when another input is made. (this can also be done within Galil)  Looks to me like Mach 3 doesn't have this at all.

Its also possible to write direct low level Galil programs and have the host just monitor position in Camsoft. Very useful for things like jogging with operator panel buttons, machine homing, rigid tapping, etc. looks to me like Mach 3 does not have this.

FWIW, I have a HUGE amount of experience working with the Galil motion products. Let me know if i can help.


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## Rbeckett

Just a quick heads up, There is a fellow on the Gecko controller group who has a surplus of more powerfull stepper motors for sale for a pretty decent price.  Go to the Gecko group and read his post if you are interested.  Here is the link: https://groups.yahoo.com/neo/groups/geckodrive/conversations/messages/22354  This will take you directly to the thread.

Bob


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## Eddyde

JimDawson said:


> Regarding Mach3 and Galil
> 
> Mach4 may solve the problems I had with Mach3.  What Mach3 did along with the Galil plugin is to try to operate the Galil card like a parallel breakout board, and that just overloaded the Galil buffer with hundreds of commands / second, rather than letting the Galil card actually control the motion.  All of the motion control was being done in Mach3.  The way it should work is to send a translated G-code line out to the Galil and let Galil figure out how to best execute the move, that is what is does for a living.  IMHO whoever wrote the Galil plugin for Mach3 made a tactical error in the way they approached the task.
> 
> The above problems are what prompted me to write my own controller software, which I'll give away for free to anyone that can use it.  It will only work with Galil products.
> 
> The best deal I could find on a 2908 module is $208.50, the 36 pin cable may be available from Galil, I can't find it anywhere else.  If you use closed loop steppers, you won't need the 2908 module unless you want to use the AUX encoder inputs for another purpose.
> 
> Another option is to operate the steppers in velocity mode rather than step and direction.  Then you would use the Main Encoder inputs for encoder feedback, and use the +/- 10 volt analog command signal to drive the steppers amps.  In this mode, the steppers act just like servo motors.  You do have to use stepper drives that will accept the analog input signal, normally +/- 5 volt or 0-5 volt input.  It's no problem to program everything to do this.  In a few days, I should have a couple of stepper velocity controllers that I bought for a project, I'm going to see if it's possible to run them from a Galil command signal.



The work you've done on your mill is very impressive and and a huge inspiration.
 I hear what you are saying about the Mach 3- Galil interface, I am not married to using Mach 3, it just seemed like a good software at a very reasonable price. I am very interested in trying your software once I get to that stage. Otherwise, I found Mesh Cam and G-Wizard I wrote them about compatibility with Galil and am waiting to hear back. I did hear back from the Mach 4 folks and they said there is no Galil plug-in at this time. 

I am leaning towards using brushed DC servos as they seem to be the best as far as accuracy, performance and are reasonably priced. Ideally, I would like brushless DC or AC servos as the seem to be the very best, but the prices I've seen so far are a bit (way) too steep. Basically I will start out with 3 axis on a Bridgeport size mill. I was hoping to spend about $1K for the motors, rotary encoders and amplifiers/drivers, package (not including the motion controller and its associated hardware). The stepper in velocity mode sounds interesting, I would like to explore that possibility further. 

Then there is the issue of having linear encoders on the load, the Galil instructions say, to make them the primary encoders and the motor encoders the auxiliary, for their "improved dual loop" system (link to the Galil video).



So it looks like I will need the 2908, I've been watching eBay hoping to get a deal on it but if not, I'll get the one for $218. The cable is another issue. no one seems to have it. I might have to make one.

Many Thanks for you help.

Eddy


----------



## Eddyde

*Re: more cnc Q.*



Karl_T said:


> When you get into it, I'd like to know how Mach4 does things with Galil.
> 
> For example, when any input changes state, Galil sends a computer "interrupt" signal to the host computer. In the case of Camsoft, the host will then scan all inputs and run any code that's called out.  The simplest examples is halt motion when a limit switch is hit or just turn on the coolant when another input is made. (this can also be done within Galil)  Looks to me like Mach 3 doesn't have this at all.
> 
> Its also possible to write direct low level Galil programs and have the host just monitor position in Camsoft. Very useful for things like jogging with operator panel buttons, machine homing, rigid tapping, etc. looks to me like Mach 3 does not have this.
> 
> FWIW, I have a HUGE amount of experience working with the Galil motion products. Let me know if i can help.



Thanks for the lead on Camsoft It looks like a great software but even the cheap-o version is way over my budget, at least for now. I also need a good CAD software, all the various hardware... Oh and a Mill too 
I greatly appreciate any help you can give me. 

Many Thanks

Eddy


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## JimDawson

Thank you for the kind words.

IMHO, there is no need for a dual loop system if the encoder is on the load.  No encoders are required on the motors for positioning if there are encoders on the load.  The really nice thing about only looking at the load for positioning is that there is zero backlash no matter what the lead screws are doing. (within limits)

Brushed DC servo motors normally have a tachometer on them that feeds back to the drive (amp) for speed control, this is not part of the servo loop.  You can get away with lower torque (and thus less expensive) BLDC or AC servos than steppers because they won't decouple like a stepper.  Most BLDC and AC servos are Hall comutated and this is fed back to the amp just like the tach output on the DC servo for the speed control.  I'm using a combination of DC servos on the X and Y, and a stepper operating in velocity mode on the Z.  The Galil card doesn't know it's running a stepper, it thinks it's a servo.

The load encoders could be rotary encoders on the leadscrews, or glass or magnetic scales on the table/quill.  My preference is magnetic scales.


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## Karl_T

Just a note, the improved dual loop from galil is not available without <expensive> hardware upgrade to the galil card.

I'm installing a linear encoder on my mill in addition to the rotary. I'll play with destination control and dual loop control soon.

From what I've read, you won't be happy with Mach over galil until they upgrade.

I'd either toss the galil idea and get step servo drivers to go Mach.
Or even better, toss the galil idea and go linuxcnc with standard servo setup.
Or try out Jim's software.
Or take the DEEP plunge and go Camsoft.

my 2 cents

my


----------



## Eddyde

JimDawson said:


> Thank you for the kind words.
> 
> IMHO, there is no need for a dual loop system if the encoder is on the load.  No encoders are required on the motors for positioning if there are encoders on the load.  The really nice thing about only looking at the load for positioning is that there is zero backlash no matter what the lead screws are doing. (within limits)
> 
> Brushed DC servo motors normally have a tachometer on them that feeds back to the drive (amp) for speed control, this is not part of the servo loop.  You can get away with lower torque (and thus less expensive) BLDC or AC servos than steppers because they won't decouple like a stepper.  Most BLDC and AC servos are Hall comutated and this is fed back to the amp just like the tach output on the DC servo for the speed control.  I'm using a combination of DC servos on the X and Y, and a stepper operating in velocity mode on the Z.  The Galil card doesn't know it's running a stepper, it thinks it's a servo.
> 
> The load encoders could be rotary encoders on the leadscrews, or glass or magnetic scales on the table/quill.  My preference is magnetic scales.



Yes I want to put linear encoders on the load, in order to eliminate backlash error and achieve maximum accuracy.
The Galil site seems to say the best way to do this is through the "improved dual loop" but I take it you have had success with only the load feedback loop going to the controller and the motor feedback loop going only to the driver?

So you think I can get away with lower torque BLDC or AC servos? That would be great but may still be too expensive as the drivers are very pricy as well, I am struggling to figure out what that torque is. So far, I figured 750 watts for Brushed DC and around 1200 oz in for Steppers, this information is from others who have converted Bridgeport sized mills, what would the torque requirement be for BLDC or AC servos? I would appreciate any insight. Also is the torque requirement the same if a stepper is used in velocity mode vs step and direction?

Many Thanks,

Eddy


----------



## JimDawson

Eddyde said:


> Yes I want to put linear encoders on the load, in order to eliminate backlash error and achieve maximum accuracy.
> The Galil site seems to say the best way to do this is through the "improved dual loop" but I take it you have had success with only the load feedback loop going to the controller and the motor feedback loop going only to the driver?
> 
> So you think I can get away with lower torque BLDC or AC servos? That would be great but may still be too expensive as the drivers are very pricy as well, I am struggling to figure out what that torque is. So far, I figured 750 watts for Brushed DC and around 1200 oz in for Steppers, this information is from others who have converted Bridgeport sized mills, what would the torque requirement be for BLDC or AC servos? I would appreciate any insight. Also is the torque requirement the same if a stepper is used in velocity mode vs step and direction?
> 
> Many Thanks,
> 
> Eddy



My mill holds +/- 1 encoder count, theoretically equivalent to +/- 0.000039 in all axis.  I guarantee it won't machine that close, just due to tool spring.  Nor could I measure that close anyway.  As best I can measure, I can hold 0.0005 over 12 inches.

750 Watts or maybe a bit less would be about right for brushed DC and BLDC motors, as is 1200 oz in for steppers. I think the brushed DC servos on my mill are about 500 oz in.  I'm running the motors at 80 volts rather than the original 100 volts, and the maximum measured output to the motors 30 volts at 100 IPM.  I did this because the stepper runs on a 80 volt power supply, and I wanted to just use one power supply.  The Z axis is a 1200 oz in stepper and I cut the torque back on that to about 1/2 power.  Normally you are running the motors at a fraction of their rated power, so theoretically you could get away with less power.

Yes the torque requirement is the same in both velocity and step mode.


----------



## Eddyde

JimDawson said:


> My mill holds +/- 1 encoder count, theoretically equivalent to +/- 0.000039 in all axis.  I guarantee it won't machine that close, just due to tool spring.  Nor could I measure that close anyway.  As best I can measure, I can hold 0.0005 over 12 inches.
> 
> 750 Watts or maybe a bit less would be about right for brushed DC and BLDC motors, as is 1200 oz in for steppers. I think the brushed DC servos on my mill are about 500 oz in.  I'm running the motors at 80 volts rather than the original 100 volts, and the maximum measured output to the motors 30 volts at 100 IPM.  I did this because the stepper runs on a 80 volt power supply, and I wanted to just use one power supply.  The Z axis is a 1200 oz in stepper and I cut the torque back on that to about 1/2 power.  Normally you are running the motors at a fraction of their rated power, so theoretically you could get away with less power.
> 
> Yes the torque requirement is the same in both velocity and step mode.



I would love .0005" accuracy  So I will try it you way, then if for some reason I cannot get it to behave I can always reconfigure it to the Galil dual loop system. The only hardware I would need to add is the 2908 and the illusive 36pin cable. I do like the philosophy of "less is more" so hopefully I won't have to go that route.

The motor info is very helpful. I'm still leaning towards Brushed DC as they are relitively cheap and their amplifiers are as well, unless there is an advantage to using steppers in velocity mode? On that note, Im curious to know why you chose the stepper Z axis? Also, if steppers are use in velocity mode do they still retain ther holding torque when not in motion? That might be an advantage?

Many Thanks

Eddy


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## Eddyde

Karl_T said:


> Just a note, the improved dual loop from galil is not available without <expensive> hardware upgrade to the galil card.
> 
> I'm installing a linear encoder on my mill in addition to the rotary. I'll play with destination control and dual loop control soon.
> 
> From what I've read, you won't be happy with Mach over galil until they upgrade.
> 
> I'd either toss the galil idea and get step servo drivers to go Mach.
> Or even better, toss the galil idea and go linuxcnc with standard servo setup.
> Or try out Jim's software.
> Or take the DEEP plunge and go Camsoft.
> 
> my 2 cents
> 
> my




The Mach 3 isn't etched in stone, so I will explore other software options. To start, I will likely take jim up on his generous offer and try his software. If it plays well with my system, happiness will abound!

The Galil DMC-2240 controller already has the dual loop capability built in. So if I go that route, I would only need to add the extra interconnect module and cable, about $300, not too bad. Ironically I only paid $275 for the motion controller NOS, about 1/10 its original cost.

Pleas keep me posted on how your dual loop set-up goes?

Many Thanks

Eddy


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## JimDawson

Eddyde said:


> On that note, Im curious to know why you chose the stepper Z axis? Also, if steppers are use in velocity mode do they still retain ther holding torque when not in motion? That might be an advantage?
> 
> Many Thanks
> 
> Eddy



The primary consideration was cost and I have had experience setting these up this way.  I also wanted a lot of torque at slow speed in a compact package.  They still are a stepper motor with 100% holding torque.

The velocity mode is generated in the drive and thus does require a drive that will do that, most of the ones you find on ebay won't do that.  The drive accepts a 0-5 volt command input from the Galil card, and then converts that internally to step and direction at 20,000 steps per revolution.  You can program the Galil motor command signal to anything you want.  When you get to that point, Karl or I can walk you through it.


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## JimDawson

Just a little teaser, here is a screen shot of the current version of my software.  I just grabbed this of of my office computer so the Galil card is not configured for this software.  This is a work in progress, every time I find a new feature I want when I'm running the machine, I just stop right in the middle of a job and make it work like I want.


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## Eddyde

JimDawson said:


> Just a little teaser, here is a screen shot of the current version of my software.  I just grabbed this of of my office computer so the Galil card is not configured for this software.  This is a work in progress, every time I find a new feature I want when I'm running the machine, I just stop right in the middle of a job and make it work like I want.



Wow! That looks like a pretty well polished program you wrote, impressive. I will take you up on the offer of a copy, Many ManyThanks!!! I should have the PC sometime next week. Now I have to make a final decision on the motors...


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## Eddyde

*Re: more cnc Q.*



Karl_T said:


> I'll only speak for Galil cards with my control, Camsoft. The Ethernet connection does not work as well as having the card right on the computer's PCI bus. I go with the HP/Compac because its plenty big enough to take the oversize Galil cards.
> 
> Ethernet may be fine for other uses with Galil.
> 
> Karl
> 
> EDIT, my bad, i just answered without reading above. sorry to mess up this thread.
> 
> Mods can you move it?



Karl,

I decided to take your advise and not go with the mini computer. it's not that doubted it would work, just that If it goes south, a replacement might be hard to find. I like your approach of using the same, readily available components to build the system. So I ordered a compact Dell desktop, Dual Core Pentium 3.4 GHz, 4/500 GB,  Windows XP P. They seem to be in abundance on the Bay.

Many Thanks

Eddy


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## Karl_T

*Re: more cnc Q.*



Eddyde said:


> Karl,
> So I ordered a compact Dell desktop, Dual Core Pentium 3.4 GHz, 4/500 GB,  Windows XP P. They seem to be in abundance on the Bay.
> 
> Many Thanks
> 
> Eddy



Good choice. Once you're up and running, i suggest you get another identical unit and clone it. Then it only takes a minute for a complete brain swap. You WILL have an issue where you suspect the computer.


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## countryguy

Evening everyone.  Awesome thread here!   Just a few Qs if I may?  
Outside of Mach3 or 4. 
Q1: What else is there when trying to get closed loop performance with a PC component that plays well with the steppers and such. Drivers for Mach 3/4 seem hot or miss.  Amen for Jim and his work on some software!   

Q2:  from Jim's post on an attempt with Mach 3.  It seemed he is noting that mach3 and the controller do no play nice  unless you can get into velocity mode.  Is that what we're trying to solve here w all the new gear? 

I am in the first 15-20% of a mill upgrade too?   So I feel your pain in all the decisions and reading  going on.  Man this is Fun stuff though!  

I just ripped out an 80s setup that Karl knows well!  Bandit 3.   I had DC servos already on so I elected to go with the Centroid controller and software.  But I was really close to putting in the stepper setup! 
      For my small hobby mill I would love to review more of this type of closed loop micro stepper setups. Wow is the tech changing ever so fast.


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## JimDawson

countryguy said:


> Q1: What else is there when trying to get closed loop performance with a PC component that plays well with the steppers and such. Drivers for Mach 3/4 seem hot or miss.  Amen for Jim and his work on some software!
> 
> Q2:  from Jim's post on an attempt with Mach 3.  It seemed he is noting that mach3 and the controller do no play nice  unless you can get into velocity mode.  Is that what we're trying to solve here w all the new gear?



Good questions.  I will only address Mach3 here, I've had no experience with Mach4.  Thank you for the kind words. 

Using Mach3 with closed loop steppers might work OK, I have never had the opportunity to try it.  IMHO that is still only a partial fix.  The closed loop stepper motors will try their best to go where the program tells them to go, but the program still has no idea what the motors are actually doing.  But still much better than an open loop (or more properly, no loop)  Without error correcting feed back (servo loop, that is updated every few micro seconds) the system can not be accurate all the time.

I have found that real problems happen if you undersize the stepper motors or you are using the correct steppers and try to run at higher speed.  If the motors lose pulses there is no way to compensate because the controller program has no idea what the motor is actually doing.  I have not had this problem running at low speeds and low acceleration rates.  There is one other factor and that is the Windows OS, if it decides to go do something else for a bit, Mach3 gets confused and loses its mind. The fact that ArtSoft can get their software to run on Windows at all is a testament to their creativity.  In Mach3 have only used the standard parallel interface and the Galil plug-in.  IMHO the gentleman who wrote the Galil plug-in made a tactical error in the architecture of the software.  He tried to make a parallel port out of the Galil controller rather than letting it do the heavy lifting.


Mach3 won't work at all with steppers in velocity mode with out adding a motion controller of some kind and encoders because position feedback is required.  There are a few motion controllers available that may be compatible with Mach3, at least their advertising indicates that they are, I have no personal experience with them.

In velocity mode, the stepper acts exactly like a servo motor under analog control, and the servo loop must be closed.  Most stepper drives do not have the capability of operating in velocity mode.  The analog input signal is converted to a bi-directional pulse train inside of the drive, normally in the 20,000 pulse per revolution range.  The motion controller normally would not know it is running a stepper motor.


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## countryguy

I did reach out to the MachMotion folks about their closed loop servo setups.  They use a middleman controller as you suggested here.  Called the Apollo III. I think it's more or less a MAch3 converter to Servo Drive setup.   The Motors seem to be in charge of watching the feedback loop and getting the motor where it needs to be.  Here is their reply on the unit:  The servo drives are making the positioning corrections. The Apollo III is checking the feedback to verify that the drive got in position, but the drive is making the corrections.   

The setups include the use of the AC servos w/ their unit, But Mach 3 has no way of getting that info back from the Controller.... They are simply DRO's.  Nor did I see how you would get Linear Scales involved and into the loops either w/ Apollo III or Mach3 but I'm open if someone has thoughts or has done it. -I did not ask that specific question.   
In the end it just seemed like trying to get tech press-fitted into MAch3 which is stepper based originally (from what I can tell)  And then to add in w/ some Servo drivers& plug ins' to MAch3 seemed the wrong way to go for me personally.  The son is 17 and I did want him to also use some Industry Standard setups.   We love Mach3 on the Plasma and Hobby Mill.  And I will get into Closed loop Stepper work at some point....  Just no time at present.   That also was part of the decision process. 
  Just some low-end thoughts. 

Oh, btw- before I forget- Then I found these guys:
https://www.teknic.com/model-info/CPM-SDSK-2321P-RLN/
They have a some cool tech but they did not seem to be out there in the market just yet?? Being a newb  -Not sure of everyone in this closed loop and servo world!     Here is a ref. they sent me to someone using the stuff. 
http://youtu.be/oBGN7E8JBKE


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## rdean

Just another option,
I have two machines I have converted to  Allen Bradley servo drives and 860 watt motors.  These used A/C drives and motors are commonly found on e_bay for about the same price as new stepper units. They are bullet proof and built like a tank.

I was running a 2 1/2D program when the machine ran up against a hard stop. (my fault)  I reset Mach and sent the machine back to 0,0,0.  The machine went back to the original start location spot on.  
No problems in over 4 years.

Ray


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## Eddyde

rdean said:


> Just another option,
> I have two machines I have converted to  Allen Bradley servo drives and 860 watt motors.  These used A/C drives and motors are commonly found on e_bay for about the same price as new stepper units. They are bullet proof and built like a tank.
> Ray



I'm curious to know, What type machines & what size?


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## rdean

An RF45 and a RF31.
Ray


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## Eddyde

JimDawson said:


> 750 Watts or maybe a bit less would be about right for brushed DC and BLDC motors, as is 1200 oz in for steppers. I think the brushed DC servos on my mill are about 500 oz in.  I'm running the motors at 80 volts rather than the original 100 volts, and the maximum measured output to the motors 30 volts at 100 IPM.  I did this because the stepper runs on a 80 volt power supply, and I wanted to just use one power supply.  The Z axis is a 1200 oz in stepper and I cut the torque back on that to about 1/2 power.  Normally you are running the motors at a fraction of their rated power, so theoretically you could get away with less power.



Hi Jim,

Im going with the brushed DC servos on all three axis, I just need to settle on the size, I was considering this one:

KL34-180-72 (NEMA 34) Dual Shaft, Front Shaft 1/2" Rear shaft 1/4":
1125 oz-in Peak 72V/40A
Green is Ground, Red is +, Black is Common)
Constant Torque: 226 oz-in
Peak Torque: 1125 oz-in
No load Speed: 4000 R.P.M
Terminal Voltage : 72 VDC
Continuous Current: 7.8 A
Peak Current: 40 A
Weight : 4.25 Kg
Skewed Rotor Design

I think it will be more than enough, just want to be sure.

Also, I have the computer up and running so I would like to take you up on your generous offer of your software. Please let me know how I can get a copy, I would greatly appreciate it.

Thanks

Eddy


----------



## JimDawson

Hi Eddy

I sent a PM (now called a conversation I guess) with the link to my software installer.  If you don't get it, let me know and we'll try plan B

I think the motor will work just fine.  Looks like plenty of power.
.
.
.
.
.
.


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## gt40

I looked up my conversion for my PM45M mill(rf45 clone)

Fixed costs not counting a rf45 type mill breaking down as follows:

$1300 for 950 watt 3 axis dmm tech ac servo kit: http://dmm-tech.com/Files/DMMTechnol...ue_Rev.1.1.pdf

$100 to $200 for 1 shot oiler: http://cnccookbook.com/CCMilllOneShot.htm

$450-$600 for 3 ball screws + ball nuts = c7 class (you can also spend 10k per axis on this one) decent site on someone doing a conversion:http://www.graetech.com/index_files/Page1897.htm

$100 for belts, pulleys from spi- si: http://www.sdp-si.com/eStore/CoverPg...Components.htm + good additional info: http://cnccookbook.com/CCMillCNCServos.html

$50-$100 for material costs for brackets to mount the servos

mach 3= $175 http://www.machsupport.com/purchase.php

$25-$ 100 PC case for servo control box

$100- $200 PC running xp, vista or window 7 http://www.tigerdirect.com/applicati...Price%3BPrice4

I would really look at just going with servos. I have used the 750 watt DMM servos on the mill and 400 watt on the Jet 13x40 lathe.  the 750 watt ones move the 400 lb head  assembly with authority (2 to 1 gear ratio) and they have real support.  They spent literally hours on the phone setting up Mach3 with me before I knew anything.  In hind sight, it is really plug in play

Here is the full build log of my mill conversion if it is any help:

 http://www.cnczone.com/forums/vertical-mill-lathe-project-log/149951-cnc.html


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## Eddyde

So far I have  spent:
$275. Galil DNC 2240 Motion Controller.
$325. for 4 Galil 12-80 Servo Amplifiers (Drivers).
$850. for 3 servo motors with rotary encoders and 1 power supply.
$150. for Dell Computer with keyboard, mouse & Windows XP
$150 for Galil ICM-2900 Opto-Isolated Interconnect Module with 100 pin cable.
About $100 on miscellaneous stuff.
Things I had on hand:
20" LCD Monitor.
Gutted Mac G5 computer for the electronics package enclosure.


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## boodogboo

I have about the same questions. I have a smithy 1324 max I was considering doing a CNN on just the lathe anyone have rough cost to complete the project and who and where to get the parts to do it. I know nothing  I guess here would be first place to start.


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