Hello everyone. I have a question about the z axis movement related to the “layer” or “color” and the behavior related to running a job or more specifically, when the job finishes.
Let’s say I am working on a job that I set the z axis @ 3 different levels, 5mm, 10mm, 15mm to account for curvatures of the material. Before the job the z axis was zeroed out, then I manual move the z axis to 20mm offset. Then the job proceeds and moves from 10mm to 5mm to 15mm and everything moves as expected.
The issue is, when the job finishes, the z axis automatically zero’s itself out. It doesn’t return to the 20mm height that I manually set the machine to. This is a big problem if the material is thicker than the zeroed height and the nozzle digs into the project or surrounding jig.
So the question is how to I prevent it this final z adjustment or move it off of the project before it does this? Is there a setting I overlooked?
If your machines are similar to my 60 W CO₂ laser, the platform rides on big leadscrews sticking up from bearings bolted to the machine frame. Two of the four have snug top constraints, but the other two are free to move, because the designers knew the leadscrews are not precision items.
As the leadscrews turn, I can watch the platform move in a gentle circular motion a millimeter or two in diameter in the XY plane as it travels in Z. The error is worst at the top of the Z axis travel where the platform is near the end of the unconstrained leadscrews.
Although I haven’t done any multi-level work, I know the cuts on any two levels will not be aligned.
If your work requires alignment to better than a millimeter, make sure the machines aren’t messing with your setup!
