Servo on Taig with Gecko

[Jcadwell]

I'm thinking about going to Servos on my Taig, and using geckos. The stock unipolar motors seem to limit speed and precision, and just don't run very smoothly, with either the Taig program or TurboCNC. Turbo is better, but the machine still makes bad noises when multiple axes are run concurrently. IMO the power supply may not be big enough.

I'm looking at the Poly-Scientific motors on the HomeCNC site, and Gecko 320s. Any thoughts? Is this overkill? What capabilities would I get in terms of speed and power. How does this compare to the 200 oz-in steppers I have now, with the Microproto controller. Ideally I want faster speeds without losing steps, and a smoother running machine that does vibrate at weird feeds and speeds.

Any thoughts? Is this overkill? This is christmas, so I'm swinging for the fences.

[HomeCNC]

I'm looking at the Poly-Scientific motors on the HomeCNC site

Jcadwell,

Don't get my larger servo motors. I have a few cases of the "Cheap Servo" motors that I got, and I am doing some machining to fit encoders on them. They will work great on your Taig! They are 360 oz/in Peak.

With the cost of the motors, encoders and machining time I'm going to be offering them for $75.00 each plus shipping. This should save you a few bucks over my larger ones. Send me a note if you are interested.

[balsaman]

What sort of driver are you using? voltage, full step or 1/8th step?

You may be able to get what you want with the exsisting steppers and a better driver and PS.

Eric

[Jcadwell]

I'm using the microproto driver with Taig's unipolar motors, and I've tried both 1/2 and full step using TurboCNC and Microproto's driver package.

One stepper motor will work okay by itself, and the whole system will work reasonably if you run the speed waaaay down, but I've had problems with running multiple axis cuts (like a radiused corner) with one of the motors stalling and screwing up the cuts. This is cutting 1/16" FR4-G10 material, or aluminum sheet in about the same thickness. The mill will cut it all day long if I only use one stepper motor for power feed. The big problems occur with two or more motors. Makes it hard to cut anything but straight lines. This is with cut speed in the 1-6 IPM range, which I feel is slow.

The table also makes lots of harmonic noises due to the ramp up and down of the motors, and I've had to pick speeds that minimize that effect. I don't think it sounds healthy. When using one motor most of that is elminated.

In my feeble brain, going to servos will make the entire system faster, smoother (no terrible noises), and more precise. Correct my eronious ways...

Thanks, John

[DDR]

I just went through the same thing. The fix is to use xp and mach1.
I had problems for 2 months until I did this trick. I set it up in an hour or so and we started cutting parts today!
Now the machine runs great and SOUNDS great!
I have the same machine, driver and motors.


I have another taig with servos and drivers from supercam. I have had it for 1.5 years now.
It is great. I converted the programming to deskwin nc.
This one is sweet!