@lhawes To dial in extrusion multiplier I use this
https://grabcad.com/library/frc1989-filament-dial-in-1
and Then measure with a caliper. The walls are 1, 1.25, 1.5, 2, 3mm respectively it also can show some slicing problems like if there are gaps and/or lets say the 1 mm is dead on but the 2mm one is way off. It has enabled us to tune the printers to a point where we can print stuff in HIPS (which we pick up for $10 or less / kg and get all the problems worked out and then print it in Taulman 910 and expect dimensional accuracy to the point. So I can print a planetary in a mix of HIPS. ABS, PETG and Nylon and expect it to mesh - not that I wanted to do that as a practical thing