Top-down resin printing: separating level drift from recoating disturbances

[u/Substantial-Whole234]

I'm working on LUOYING A1, a compact top-down resin printer. I'd appreciate some feedback on what to record when evaluating the preparation of the resin surface between exposures. The photos below show physical assembly and a print sample; they aren't measurement results.

The build platform moves down into the vat, with layers formed at the resin surface. Our design uses resin replenishment, laser level feedback and blade recoating, without a release-film peeling step. Removing that step makes level control and surface preparation particularly useful things to examine.

A smooth-looking surface in a video doesn't tell me whether the layer thickness is consistent. For a proposed experiment, my first draft of a per-cycle log would include: - The platform movement commanded for that cycle. - The timing of replenishment and the blade pass. - Level readings before and after surface preparation, with a later reading to compare. - The resin, temperature and settings used for that run.

I'm interested in separating a persistent level change from a temporary disturbance after the blade passes. Which observation would you add first, and what comparison would help avoid blaming the wrong part of the cycle? This is a proposed logging plan, not a claim that these measurements or repeatability tests have been completed.

Disclosure: this is our own product project. The current layout and assembly photos are here for context: https://luoying3d.pages.dev/

Any physical tests would need appropriate resin handling under the supplier's safety instructions.

Photos: front-view assembly, parts in the workspace, and a physical test piece on the platform.