Calibration 20mm_OD 10mm_ID Cube

I use this for calibrating parts that don't fit well together. I'd rather the outer be a little too small and the inner be a little be a little too big than the other way around.

My printer had been overstepping all x-y bounds of models by a tenth of a millimeter or so, but that adds up when parts are trying to fit together tightly.

I found a setting in Slic3r under the advanced tab called "XY Size Compensation" and set the value to -0.16 so it shrinks the model dimensions to account for