My younger bro had me 3D-model a simple circular sieve for testing the leveling of our Monoprice Mini-Delta printer, which seems to be having a minor issue. (When we'd start a print, the first several layers were 'thinning' on a particular side of the build-plate; it turned out to be a belt-tension issue!)

Have at it.

That is all.

UPDATE: Wow, so much interest in this thing! O__O
So I thought I would let everyone know: Actually, just printing a 1mm x 1mm cube with a GIANT raft (enough to fill the build plate) worked better as a test than this sieve did. Because when we tried to print this sieve, for some unfathomable reason the printer decided that it would go about it by printing ten-thousand tiny circles instead of a proper series of lines. So yeah, just fill the build plate with a giant raft, and it will print in lines instead of tiny circles.

I guess on might say that........
These printers are a kinda loopy! :->