Laser drifting south

I have a new 6090 co2 laser with Ruida 6445 controller. I am new to laser use but have CNC experience. My machine works fine if I am doing an image but when I am engraving on vectors it slowly drifts south on the Y axis so that at the end of 20 lines of text it is almost .250" below where it should be. I have put every line of text on its own layer to minimize the visual effect but the upper lines do not end up aligned with the pre-drilled holes for that line. I make games and want to use the laser to do the marking. I have lubricated the rails and snugged up the belts. I have ordered a 36V power supply for the steppers. Are there any other suggestions that I could look into? Thanks.

If you draw and engrave a large square, does it hold accurate measurements?

Thanks. I did a large rectangle and repeated it a few times. I did not notice any drifting. I added 30 hexagons to the interior of the rectangle and each time I repeated the combined design it was consistently shifted very slightly to the Y-. There is no noticable shifting on the X axis. The shifting is consistent and repeatable. I engraved a mermaid and when it got back to the scales on the tail they never lined up. I tried different speed settings without any change.
It seems that the machine is dragging when headed in the Y+ direction. It might be in the acceleration settings or it might be mechanical. I don’t know what are appropriate acceleration settings for this machine. I have lowered them to 500mm/s/s without any change in the drifting.
Thanks for any ideas.

Have a look at this post:

Thank you for that information.
I will check that this evening. Hopefully it is as simple as that.

Thank you very much.
I changed the Y pwm setting to match the X setting and everything is lining up now!

1 Like