Surface Mate Demo

This is a demo of a technique I've used in recent designs to very easily fit parts with zero added clearance. The idea is simple, angle the mating surfaces very slightly (3 degrees in this demo) to allow the prints and layer lines to mate with a slight press. By taking advantage of arc fitting and the inherent accuracy of STEP files it's possible to design and print very complex geometries that press-fit together almost seamlessly.

All parts pictured were printed on a Bambu P1S using Bambu Basic PLA and the included print profiles; no filament calibration was applied to any of the filaments.

Design Tips

• When sketching along the XY plane try to avoid making sharp edges; use curves or apply a fillet to sharp edges after extruding.
• The slicer will try its best to hide seams; small rounded corners provide perfect locations to hide seams and work well for aligning pieces.
• Use your CAD chamfer/draft tools to angle the surface of the inner part and then use a boolean operation to make the cutout from your outer part, no extra steps adding clearance needed!