Y Axis Jerk

[mrwetzeledtech]

Running into an issue that we haven’t noticed before. It’s seems as if there is some wobble/jerking in our Iconic 8 machine because the right side of the gantry seems to take off a bit quicker than the left side. The marks in the picture were made by manually moving the spindle to a scrap piece and then lowering it near to it. After turning on the spindle and then lowering into the stock a bit (0.5 mm ish), we’d move it in the y+ direction. You can see that when doing that, the bit jerks to the right and then makes a straight pass. What would cause this jerk to the right?

We've checked it for looseness in different areas, and have tried to ensure everything is tight (although we may have not checked every applicable area). We did find that when holding down the y-travel button (in positive or negative direction) the ball screw rotates a little bit, then takes off in a normal fashion. The jump doesn't seem like it should be normal. I have attached a video of this.

Thank you for any advice on how to fix.

Attachments:

IMG_7499.MOV (1.79 MB)

[Bob]

With everything turned off on the machine. Try to manually push the gantry along the X axis. If there is any movement, try to isolate it.

I don't know what "different areas" you have tried, but check by trying to rotate the X Y , And Z couplers by hand. Sometimes the setscrews become loose and there can be some play where they connect. Check to see that setscrews are positioned squarely on the flats of the drive screws and motors before tightening them.

Bob