Need Help!- Mach3 Mill 2 problems

[Highfly]

Hi All.

I do not know a lot about this system but I am trying to help a friend with it.

This machine is used for cutting plexi glass and has a router on it. X,Y and Z axis.

Two problems we are having. One is when doing a manual movement in the Y axis(Y axis has two stepper motors) one motor will sometimes stop moving half way through a long manual movement.
If you put a movement in the program to have the table automatically travel the distance no problems.

Second problem. When doing circles we are out of round on large circles it seems. A 2" circle looks to be perfect. a 20" circle is out by approx .125" (oval). The start and stop location perfectly matches, no step at all.

I thought backlash but one would think you would see it on small circles.

Any ideas?

[ger21]

Does the motor just stop, or does it stall and make a grinding noise? You may need to slow down the velocity a little in motor tuning.

As for the circle, what if you cut a large square? is it the right size? The steps/ unit may need adjusting.

[Highfly]

Thank you for your response. I'll ask him as I wasn't there, but I will get back to you!

[Highfly]

OK the problem with the manual movement hasn't return since I made new stronger servo brackets that have adjust ability to them so I could set and hold the back lash in the gears better.

The problem with the circle does also happen with a large square.

[ger21]

Then you probably need to adjust your steps/unit in the motor tuning screen so that you get accurately sized larger parts.

[Highfly]

Thank you once again for your response. I'll grab the manual and see if it touches on this. Is it safe to say you play with this number and test in a real time application to get it perfect?

[ger21]

Basically, yes.