G540 + EMC2 = missing steps

Rick G wrote: Hello,

Have you tried setting the spindle up high and with the spindle off cutting the part in just air?
Do you get the same results?
If not you might look for mechanical or noise problems.
Also try reducing your speeds both rapid and cutting.

Rick G

Rick,

Help Please. Having problem especially with circles. See attached photo. Thanks

Are you using cutter offsets and removing before retraction, would look similar :laugh:
regards

Arceye,

No.

My parameters;

1/16 end mill
cut2d prog.
K2cnc machine

This are cuts of circle and eclipse with no tabs. The bigger the diameter the more emphasis on the notch and is happening at the start of the cut. I have played with the velocity and accel no luck.

Thanks

Hi

Can you attach some code (complete) that is doing this.

I presume the code is generated, seems unlikely that losing steps is going to cause the cutter to go outside the radius of a circle, especially at the start of the run.

This does look just like what would happen if you only applied cutter compensation after plunging or took it off before retraction.
The point is the same for all the circles and ellipses and so far as I can see from a slightly tilted workpiece, equates to a runout of approx half the cutter width.

regards

I have seen two cases of step loss when using simultaneous motion over multiple axes:

- Case 1: the problem was the switch mode power supply. Although it was a hefty 48V/10Amp supply, it was not capable of running 3 motors at the same time. Switch mode power supplies are not good motor supplies unless grossly overdimensioned; they have problems coping with regenerative energy. Solution: I had the guy add a second power supply and power one of the axes from that one.

- Case 2: The problem was some deformation in the machine frame. When the X axis was moving the Y axis was binding and vice versa. Alignment and stiffening solved the problems.

Not sure if this is the problem here, but checking it doesn't hurt.

Arceye,

Sorry, I forgot to mention the controller is by Xylotex. See attached emc2 code.

Thanks