Elna Electronic SU Cam Stack Gear

The zig zag function on my wife's Elna Carina would no longer work. Only straight stitches.

On closer inspection, the cam gear attached to the cam stack had lost half of its gear teeth missing. This is a very difficult gear to replace as the elnagraph mechanism needs to be dismantled. So far, the 3D printed part has been working for the past 5 months without a problem. Some reaming may be needed to ensure a smooth fit on the cam stack shaft depending on the 3D printer.

A roll pin needs to be carefully removed in order to remove the existing gear. Carefully tapping a small finishing nail might help.

Revised to provide more shaft clearance and rounded the top edge.

Revised Apr 24, 2021 to adjust tooth angle. It is subtle but should improve gear life.