4" Coil Jig

This is a jig I made for the very specific purpose of making a continuous wind coil. The Inside diameter is 4 inches (101.6mm), the width is 12mm, and the height is 20mm max. It was designed to use a whole 1lb spool (823') of 24 AWG enameled copper wire.

This electro-magnet was for a project to manipulate the raster of a CRT screen.

Materials needed:
-3/8" bolt 2 or 3" in length, with washers and stop-nut (to keep it from loosening)
-x8, #4 x 1/2" Pan Head screws.
-masking tape + hobby knife or 1/2" wide masking tape.
-thin string
-electrical tape

Instructions;
1. attach a 3/8" x 2" bolt with fender washers and stop nut to the hole in center. This will connect to a drill. Choose a drill with a chuck big enough and that has good speed control.

2. apply masking tape with adhesive side out to the inner surface of the spool, trim off excess. This will make extracting the finished coil easier.

3. Attach outer flange with eight #4x1/2" Pan head screws.

4. Wrap the wi