A threading dial for my 9a.
I made the gear from nylon using a fly cutter on a horizontal mill w/indexer. The teeth are cut straight, the mounting stud is press fit into the aluminum body at the helix angle (3 deg), tilting the entire threading dial to match the lead screw. I haven't engraved any numbers onto the dial face and may not. If I ever have to cut a fractional thread, I guess I'll just mark one of the lines with a Sharpie.
Paul
I made the gear from nylon using a fly cutter on a horizontal mill w/indexer. The teeth are cut straight, the mounting stud is press fit into the aluminum body at the helix angle (3 deg), tilting the entire threading dial to match the lead screw. I haven't engraved any numbers onto the dial face and may not. If I ever have to cut a fractional thread, I guess I'll just mark one of the lines with a Sharpie.
Paul