FitCheck Calibration
Common questions
What does calibration do?
Every machine cuts holes a bit under or oversized (at least mine do!), and it's different on each one. Calibration tells FitCheck how far off yours is, so the app can automatically correct the holes and pockets it shows you. Toggle between your machines to apply each one's offset, or switch to no machine for the raw standard values.
How do I calibrate a machine?
Download the free calibration models here. There is one model for FDM printers and one for CNC machines.
FDM printers — print the FitCheck FDM Calibration Model on the printer you want to calibrate
1. Measure the three 5.00 mm holes with calipers. Measure each one twice, rotating the calipers 90° between readings, and average all six numbers.
2. Add the machine in FitCheck and enter that average. That's it - FitCheck derives the printer's error itself and corrects the holes and pockets it shows you from then on.
The model also has two optional measurements for finer calibration:
Print bearing seats or other large bores? Also measure the 22.00 mm bore (three readings, about 60° apart, averaged) and enter it. If the spread of those three is more than 0.05 mm, leave it blank and reprint: that much spread could be a blob or a lifted corner on that bore, not your machine. FitCheck uses this number to scale the correction for bigger holes instead of applying the small-hole number everywhere.
Take every optional number off the same printed part. Mixing a 5.00 mm reading from an older print with a 22.00 mm reading from a new one folds the difference between the two prints into the size-dependent correction.
Print nut pockets? Also measure the two 8.00 mm hex pockets (three flat-to-flat readings on each, six total, averaged) and enter that - flat walls print with a different error than round holes, so this number corrects hex pockets on their own. Leave it blank and FitCheck falls back to the round-hole number.
CNC machines - mill the FitCheck CNC Calibration Model
Measure its three 8.00 mm holes the same way (two readings each, rotated 90°, averaged)
Enter the average when you add the machine.
One size is enough on a subtractive machine - an endmill's error doesn't change with the bore diameter or the contour, so there's no large-bore or hex measurement to take.
enter the average when you add the machine.
Calibrating a machine is free to try. Saving it — so its offset is applied every time you open the app — is the FitCheck Pro feature. More pricing details can be found in the about page
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FitCheck is a product of Baked Bean LLC (d/b/a BakedBean3D), Illinois, USA