Motor stutter help!

[Cartierusm]

I have a home made cnc router I made out of extruded aluminum and I'm using Igus Drylin bearings for the linear slides. Now I haven't had a problem before when testing the unit. Now I went to cut somthing I designed in Artcam. Now I've only done test cuts using the Mach3 built in wizards. Now this is the first cut I've made with my own design. It worked at first then I went to cut the rest of the item and my gantry was stuttering, you know kind of jerking around. I hear a kind of squeaking noise. So I figured one of the bearings was out of alignedment. I checked and readjusted the bearing and it still does it.

NOW the weird part is when jogging around at different speeds it's smooth, no stuttering. Now the stuttering is like the bearings sticking it still moving to the coordinates it's supposed to. So like I said it jogs fine, even when pressing the keyboard keys back and forth quickly. So why would it only do it when running a program? Mind you this is a test run once I figured out somthing was wrong so the router and accessories were not on. If anyone can help I'd appreciate it.

[sansbury]

Your description may be clearer for someone else, but I'm having a hard time understanding what is happening. With that said....

The first thing I would do is open up the Artcam g-code and verify that it's not commanding the machine to do something it doesn't want to do, like move too fast. I'd start with a simple square or something that is easy for you to read the G-code and see that it's not trying to do something weird.

The second thing I would do is try to "air-cut" the program with the tool off and 1" or so above the material surface. Let's rule out anything to do with the actual cutting process. If the problem continues, slow everything down. Cut all the speeds in the program to no more than half the speed you can jog at, and try again.

There's no magic here. The key is to try boxing in each aspect of the system and then altering each one up and down until we see if we can isolate which piece causes the problem, then we can worry about why. If you can use Mach by itself then that suggests that something problematic is being introduced by Artcam.

I had a problem when I set my first machine up because I had the speed limit in the driver software set way too high. G1 commands worked fine since I had feed speeds set low enough, but when a G0 was ordered, the controller ordered the machine to go faster than it could and the motors locked. Eventually I figured out how to turn the master speed limit down and then everything worked. But first I had to figure out that it was the G0's that were the problem.