Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:3969147.

Jig for creating a Hobbed Bolt required for a Gregg's Wade's extruder. it uses 2 608zz bearings

print as imported.

removed left and right outer single wall (built in support) once print completes.

see Video for full how-to https://youtu.be/UDiAeUjKYy0