Print layers drifting towards rear

[cliffyk]

Clearly there is a good bit of slop in the design, but I'm not sure it's the source of my problem. I've just gone through more tests on zeroing and if the set screws are tightened enough (as in either one) some corner/edge of the build plate will rise above above the paper. I also checked the flatness of the build plate on my granite flat. The build plate itself seems to be very flat and even sticks a bit when one tries to remove from the granite. The newer mast/ z stage design is much better as is Jackson's design.

I found the same with my two plates, flat as that proverbial pancake we so often hear of...

My best results seemed to be by just lightly tightening the set screws. I wasn't able to slide a 0.0015 inch gauge under the perimeter at any point.

I have found that over-tightening those lock screws is common; I saw a video wherein a fellow twisted away on tyhe wrench as though he were tightening the log nuts on the rear of his F-250 "dually"...

I also use an electronic angle meter on the arm and it is 0.00 degrees in orthogonal directions both before and after zeroing. This meter is only accurate to 0.3 degrees, so it could show the deviations you measured.

The angles I presented were all calculated from linear measurements of the moment arm and deflection. I too do not have a protractor (digital or otherwise) capable of measuring such small angles..

I'm a bit worried as to if the plate will tilt during the ongoing test print. On the prior prints there must have been a lot of force to move the build plate to cause it to tilt and I think this print will be easier move out of level. Time will tell later today.

Greg

Keep up the good work, something has to be shifting dynamically. Have you tried different layer thicknesses? It is not inconceivable to me that what you are experiencing is being caused by some combination of machine precision, resin density cghanges during curing, and/or other antagonistic relationship of the system settings and components.

Often it is helpful when changing something changes an outcome--regardless of what was changed. Otherwise we are doing just what dear Albert warned against...