[Us ill]

Hi fellas,
I have a cnc 3020. Recently I noticed that if I press "feedhold" if I need to pause the toolpath for something that when I do this the bit will drop into the material surface about 1mm. It didn't do this before. I'm just trying to figure out what this could be and how I can troubleshoot this issue. Any assistance would be greatly appreciated. Thanks in advance!

[jalessi]

Us ill,

1: The end mill is pulling out of the collet.

2: The spindle bearings are bad, check the end play.

3: The stepper motor is not holding the axis position.

Jeff...

[Us ill]

Jalessi, I checked the collet and it looks to be fine. My spindle doesnt seem to have any end play when I manually try to move it up and down. So possibly it is the stepper motor. I dont know what else it could be. I have these cheap chinese stepper motors so im thinking it is this one. Is there any way to be sure. Here is a picture of the Z axis stepper motor label. Thanks again sir!

Us ill,

1: The end mill is pulling out of the collet.

2: The spindle bearings are bad, check the end play.

3: The stepper motor is not holding the axis position.

Jeff...