Circle Torture Test

Update

Made it come off as one piece.

This takes 3 min, and is very tough. At least it is for my glass bed. Getting small circles to stick is quite hard indeed.

Tests for level bed, nozzle height, bed adhesion.

You can definitely cheat on this and set your nozzle height very low (through z offset) but those settings would mush your first layer on other prints.

Things that can go wrong:
-Circles not sticking
-Circles not fully formed,
-Circles boxy looking
-Filament not extruding
-Stringing issues
-Uneven look
-Big ball of filament.

Running your finger gently over the circles should not dislodge them.
However, if a corner is sticking too tight, not coming off, you need to loosen that side.

If you managed to press it way too tight to your build surface (glass), wiping it with a slightly wet paper towel usually pulls it right off.

If you're using it with an Ender 3, I recommend using it while adjusting this:
https://www.thingiverse.com/thing:2954285