Large snap fastener for cloth (sewn) and hard surface (screw)

This 40mm (1.57 inch) circular snap fastener takes inspiration from the YKK SNAD fastener. We have a circular couch with plywood base and the cushions are often on the floor. We also have a boat seating area with fiberglass benches. This fastener is designed for one side to be sewn on to cloth and the other to be retained by a screw to a hard surface.

Some care was taken to ensure that the two parts stay together however they should not hold so well that the fabric rips when trying to separate the two parts. If anyone is interested in a stronger version, you can open up the Fusion 360 file and tweak the radius on the part of the circle that forms the snap. The current radius is set to 0.4mm however lower values (say 0.24 or so) should result in a much more difficult to separate fastener. See the screenshot of Sketch 1 with the radius focused (changing it will change both sides of the circle).

Print without supports. On my Bambu Lab P1S with a 0.4mm nozzle I used the 0.2mm strength profile.

Feb 13, 2026 update: I added "Snap (solid).stl" which has the snap side circle solid instead of having a groove. This doesn't change how easy it is to snap but it likely makes the part more wear resistant (less susciptable to damage when not snapped together).