After having some minor problems getting circles right and trying to get 608 bearings into my printed parts, I created this simple test to verify I had round holes.

An American nickel is 21.21mm in diameter, and 1.95mm in thickness. Ref(http://www.usmint.gov/faqs/circulating_coins/?action=faq_circulating_coin)

This test has an internal diameter of 22.0mm (what's 0.69mm between friends?) and a height of 1.95mm.

This test will also be a good and quick test of the "Bottom" setting, and a good way to ensure the "Fill" settings are making solid top layers.

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