Drag to rotate · scroll to zoom. Files are for personal use — no resale or redistribution.
Sliding Trammel Beam Compass
A 170 mm print-in-place beam compass (trammel) for scribing large circles and arcs — speaker baffles, table tops, plywood cutouts — at radii from 27 to 129 mm (circles Ø54–258 mm). The carriage is printed captured on a dovetail rail and slides between the two end blocks; an M4 screw in a heat-set insert (5.5 mm bore) locks it to the beam, a Ø9.5 mm bore takes any pencil, scribe or fine marker held by an M3 set screw, and an M3 screw with a captured nut at the pivot end forms the adjustable centre point.
Ordering a print of any gallery model is free once you're signed in. Want the OBJ for your own printer? Download it for $1 — no account needed, we email you the link. Signed-in members can pay with credits instead.