[Jack_K]

I took an old spark plug and drilled out the center electrode and ceramic insulator.

Then I found a piece of round metal rod that would fit inside the drilled out plug.

I cut off about 2" of the rod and "glued" it into the spark plug with JB Weld.

Still works after 45 years.

Jack
P.S. Be sure to round the edges of the rod so it doesn't scratch the piston.

 

[mrbsa]

be careful

Be careful when you are drilling or breaking the ceramic insulator. They will send chips flying and can very easily get in your eye. They are ceramic so the doctor can not pull the chip out with a magnet. Always wear eye protection.