Gunner Asch fired this volley in
:

They are obviously plugs put into the base metal.
What was the base..some sort of saw blade? It has the knock out in
the
center


That was odd, but I assumed he'd soldered a thin sheet of brass to a saw
blade backing.

He did say he was etching brass, not steel.

It's not out of the question that the conductivity of the whole affair is
different over the "cutouts".

Lloyd