So far I’ve been filling Bamboo Cutting boards and I would say it was less than 1/4" deep.
Yes, you have to sand the piece afterwards.
I have a Sculpfun S30Pro max 20W optical power but even the 5W I had before would burn deep enough into bamboo that this technque works.
We are getting sidetracked here. If people want to continue this discussion about epoxy fills, let me know and we can start its own thread instead of hijacking this one.