K40 left-right motion is jerky

[TimM]

Hi all. I just bought a 40-watt Chinese laser and am setting it up. It arrived in apparently great condition, with nothing obviously broken, bent, or missing. The laser tube works, and the software seems to have installed correctly.

But when I manually slide the head left or right, it runs smoothly for several inches, then snaps hard into a fixed spot. With some effort I can slide it smoothly and easily a few more inches, then it snaps again. This happens every few inches, across the entire extent of the range. It is as if there are a few strongly preferred positions equally spaced a few inches apart, with the head strongly gravitating to those discrete spots. The gravitation is so strong that the stepper motor cannot move it out of one to home it. If it is manually slid to the left of the leftmost snapping spot, it homes correctly. And everything is smooth and well working in the front-back direction. Any thoughts? Please???

[Thunder Laser -Nolan]

I think that the X axis is stretched taut.You can click this link solved the problem.

[TimM]

Nolan - Thank you for your reply. But I didn't see a link. Perhaps you could resend?

I discovered what is causing the jerking to preferred positions. I made pencil marks on the four tiny bearings that support the laser head transport at its four corners. The locking happens at exactly the same spot on the bearing rotation. So somehow (I can't imagine how) it's as if one or more (probably all) of these bearings has a flat spot that it doesn't like to roll over. When the bearing hits the flat spot it wants to stop there.

Tim

[Thunder Laser -Nolan]

I'm sorry I forget it http://www.thunderlaser.com/troubleshooting/hrxas.html