This Experimental uses a cut down Apollo with the side arm completely cut off. A round wire going into
a slot is the spring. No capacitor needed because there is no contact screw/spring current flow.
The full rubber band limits upward rebound.
Rubber piece on front coil keeps it quiet
and gives it rebound. The 3mm jack on the
other side which is attached by a flat plate (plastic) material provides the connection.
Make the frame from any material as long as
the coils sit on Ferromagnetic material (Yoke).

 
There is a yoke beneath the coils holding them together.
Rubber Band gives Rebound and Quiets Chatter.
A steady hand holding the spring makes this
human tattoo machine.
Make the spring(s)
out of any shape any material.
Send Photos / Comments / Questions Wes@unimaxsupply.com