Fit Type
Dimensions
The target size where the parts meet
mm
Printer Accuracy
How dialled-in is your printer? This adjusts tolerances accordingly.
Recommended Dimensions
Hole (inner part)
10.40 mm
Shaft (outer part)
9.80 mm
Designed gap (per side)
0.30 mm
Fit quality
Good
Hole offset from nominal
+0.40 mm
Shaft offset from nominal
-0.20 mm
Print a test piece first. These values are starting points based on typical FDM tolerances. Every printer, filament, and slicer combo behaves differently. Print a quick test cylinder at your target size, measure it with calipers, and adjust from there. Holes tend to print smaller than modeled, shafts tend to print larger.
When to use each fit
Clearance Fit
Parts slide or rotate freely with a visible gap. No force needed to assemble or disassemble. Good for moving joints and parts that need to come apart.
Hinges, bearing housings, removable caps, lid inserts, cable pass-throughs
Transition Fit
Parts fit snugly with minimal play. Light hand pressure to assemble. The part stays in place but can be removed without tools.
Alignment pins, snap-in panels, battery holders, sensor mounts, test jigs
Press Fit
Shaft is slightly larger than the hole. Requires force (or heat) to assemble. Parts lock together and resist removal. Permanent or semi-permanent joints.
Gear shafts, threaded inserts, permanent axles, structural dowels, motor mounts