Circle Leveling and Adhesion Test.

Circle Leveling Test
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This a quick 1 minute bed leveling test. Mainly for a **glass mirror bed** to also test adhesion.

I was having some difficulties with a large print, due to poor leveling and nozzle height. Straight lines were drawn fine, but circles, especially small ones were dragged around which were due to the nozzle height being too high. Thus, this test was born. It's a bit more stringent than a square test.

####How to use this for leveling:
Much easier to observe on a mir