Gecko 320 vs industrial

[rktman8888]

What are the limitations of the G320 and Mach in regards to accuracy and finish of a cut part? How would it compare to say an industrial control with servos and closed loop? Not a vmc, but more like a Knee mill with a high end retrofit. Can parts be made with comparable finishes and tolerances?? Using the same machine for example. Is there anyone that uses the expensive retrofitted Knee mills at work and a G320 at home. How well do the cheep drivers and software stack up? Given both would have ground ball screws and such. Talking electronics only.

Thanks

[mc-motorsports]

I prefer the word "inexpensive" to be used with gecko.

Your limited to 20 amp servo's, but there are people running Bridgeports at 300imp. I only run 120. 300ipm is probably the fastest I would want to run an open bed machine or knee mill.

As for the high end retrofits, can't help you there. I ran Mori's at my last job and own retro bridgeports, I could compare those.

I really don't think if you could upgrade from a gecko your going to get much better on a knee mill. Your limited by how ridgid the machine and spindle are. But I do some very precision tool work also, and the Gecko drives and Mach 3 work great, within the limits of the machine of course.

If you want closed loop, maybe EMC 2? I believe it's free, heard it is more difficult to set up and a little more difficult to learn. If you REALLY want closed loop, you proably want to use linear encodors for your feedback. Otherwise, the Gecko's and an open loop system like Mach 3, anything goes wrong and the servo's shut down. I've snapped 1/2" carbide endmills without losing position. I've also knocked my milling vice and fixtures out of square without losing position.

I have nothing but good things to say about Gecko and Mach3. Gecko's customer service is unmatched and Mach3 has amazing support via forums. Both do exactly what they are supposed to do, but if you want closed loop, probably EMC software. Don't shy away from the Gecko's for something that's over priced. Trust me, if you have problems like I did (the guy who sold me the drivers, servos and encodors package's fault), you'll be glad you chose Gecko because Mariss at Gecko was the one to diagnose the problem and get me up and running! No support from the guy who sold me the package deal, just a sob story about personal problems, it was pathetic.

[Konstantin]

After a while with other servo and stepper systems I got to a conclusion that there is nothing better than standard STEP/DIR drives, it will allow you to use common software and there are plenty.

As for accuracy that depends on how precise is your table design, drives will convert pulses to motion and if closed loop like servo/encoder than it will be as precise as your encoder resolution is.
Finish and tolerances pretty much depend on the machinist, the tool selection and machine play/backslash, machining speed and such. Servos just move the tool around.

Konstantin.

[rktman8888]

Thank you both for taking the time to respond. Very helpful. I do have a round column mill now with g320's and rolled screws. My problems with this machine are most likely the iron. I bought a Sharp Knee mill with a Anilam 3300 controller. It’s ten years old but in very good condition. The machine has ground ball screw and dual nuts. Servo motors, and I believe it’s a true closed loop system? My problem is Im so use to the way my Mach 3 system works I really don’t want to deal with the conversational type controler on the sharp. My thinking was to use G320's and the software im familiar with. My concern by doing so is compromising the motion control?