Tattoo Machine Troubleshooting 
#A135 Armature sticks to coils when foot pedal pressed.

Short Circuit Troubleshooting Answer # A135
Problem	Armature bar sticks to coil when the  foot pedal is pressed.
Because	The electrical circuit is shorted out. Missing insulating washer.
Check	The plastic recessed washer insulates the rear stand-off from the frame. If a metal washer is used the machine will short.
Why	Electricity will flow through any metal  that is connected by touching.
Cause	If the rear-standoff touches the frame a  new path for electricity is created.
Remedy	Install plastic or fiber recessed washer  that does not conduct electricity.

Also see  needle insertion in tube.

(Bring up separate labeled parts window) then re-size the new window and drag it to the side so that you can see both windows..