Fidget Thread Spinner Toy for Kids

This is a toy that I designed/made for my 2yo son for Christmas this year.  It is rod with left and right-hand threads on opposing sides, and matching handle “nuts” that can be grasped to pull out/in to spin the threaded rod.  My hope is to get my son curious about and interested in mechanical things.

This was made with my Bambu X1C, printed with PLA basic.  Everything was printed with a 0.4mm nozzle, at 1.2mm layer height, with a few extra wall and face layers, and 30% infill…mostly for weight.  This printed without support, but the main threads had a few rough spots that I filed/sanded to clean up.  However the parts DID fit and move together with no touch ups, but the sanding made things go a bit smoother.

The threads are very course, with a large lead angle close to 30 deg and have 4 starts to allow the handles to drop under gravity alone.

The End Caps attach with #6 x ½" Tri-Lobe Screws (McMaster-Carr PN: 99512A259)