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I currently have stepper motors on my axis drives, but have been looking at upgrading the whole drive system to servo motors and better ballscrews.

for cutting necks, bridges, fingerboards, etc,, is it worth the money for me to upgrade?

Will the same controller work for servo motors as it does for stepper motors or will I need a new controller box?

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Reguards,

Ken H

Hey Ken,

Did you ask the guys over at http://www.cnczone.com? There are some knowledgeable folks over there.

I am a mmber over there also, but I havent asked the question over there. I belong to so many forums that it is hard to keep track of them all.

I was hoping that someone over here would be able to answer with some real world experience. I know that servos are supposed to be better, but whether or not is justifies the expense for luthier work is something I cannot answer.

I ordered new ballscrews yesterday for the machine. New bearings and motor mounts also. I think this will speed me up considerably. I'm still wondering about the servo motor switchover. I see that you can buy servo's on eBay pretty reasonable in price, but I wont do that unless it makes a BIG difference.

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Reguards,

Ken H

Hey Ken
I did retrofit both my Maxnc10 as well as the Techno-Isel with servo motors/drives. Yes it does take a different controller as it needs to accept the input/feedback from the encoders on the three axes. (The encoders are usually mounted directly on the servo motors)
I retrofitted the Maxnc because it was extremely slow with the stepper setup (10IPM max). I retrofitted the Techno-Isel as the stepper controller had some problems on one axis and was extremely noisy because of harmonics developed in the steppers.
I would recommend staying with steppers at least for the time being if you are happy with their performance. They can be as accurate as servo drives or even more so if they don't lose steps causing positioning errors. Is your stepper drive/motor system fairly new? If it has adequate power to run your current acme screws (I'm assuming) it should do better with ballscrews.
Hopefully someone with more knowledge will step in here.
Nelson

Thanks Nelson!
That answers alot of questions. I bought new acme screws and they should be in on friday. They have the delrin nuts on them and I am hoping that this will glide easier than the allthread I have been using on the small machine. I actually got the allthread working on the larger table, but am not satisfied with them because they do set up harmonics that cause it to skip steps.

The acme rods are supposed to be hand polished and I know delrin is slippier than grease, so hopefully this will solve my problems. The allthread is 5/16 and the acme is 1/2" in all 3 axis.

I have upgraded form a dremel to a laminate trimmer also.

The stepper motors are fairly new and little time on them so they are pretty accurate.

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Reguards,

Ken H

Ken, what torque rating are your steppers? There are some new hybrid motors out there that perform with much higher torque at higher speeds than typical steppers. Also, if you use step drives like the Gecko G203V's you will increase the performance and smoothness of operation. I purchased some 600 Oz/In motors which have torque at higher speeds more comparable to a 1200 Oz/In motor. Mine are Rex RS34-600's.

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

I am going to need to do some research on the stepper motors. Here is a picture of the label on one of them. If anyone has any info on them, please let me know?

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Reguards,

Ken H

Ken, I'm not sure but I think this may have been an old printer motor.

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Jim Watts
http://jameswattsguitars.com

It is possible, but googling this motor number turns up quite a few avionics parts supply houses. I am suspecting that it is used on military aircraft.

It is plenty strong, but I have no other information on it beside what is on the label.

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Reguards,

Ken H