> Some of the holes are 1/2 in dia. I've tried aircraft snips & it's a
> hard cutting corners without leaving a saw-tooth edge.
> The copper sheeting is a little thicker than a manila folder. I don't
> what the thickness is. May use a gauge tomorrow to check it.
> Ideally, a scroll saw would be nice, but I'm not sure if there is a
> metal cutting blade to use.
Using your idea, create a sandwich using 9 ply Birch (1/2) and the
copper sheet using screws around the perimeter to hold thing firmly
Drill 1/4 holes thru the 1/2 holes described above.
(Makes turning the piece relative to the blade MUCH easier)
Use a scroll saw with a standard wood blade (about 8-10 TPI) to cut out
the pattern the same way my landlord makes temporary tooling to die cut
gaskets using 5/8 Birch ply.
Don't rush, this is a time consuming task.<G>
When finished, trash the blade if it has become dull which is doubtful.