It depends on the plastic. I used a nibbler on a Radio Shack plastic
box, and it was fine. It likely will crack hard plastic, but a softer
one will be fine.

You don't need to use a hot iron, you can drill plastic.

"Dremel tools" and the like are good, using the cutoff wheels. The
problem is that the mechanical arrangement limits the usefulness.
Though, they now have attachments that puts the cutting wheel at 90
from the shaft and that looks pretty good for this kind of work.

Plastic isn't really so different from metal. People used to drill a
bunch of small holes close together around the perimeter of the area
they wanted out, and then it was relatively easy to break down the
space between them. Then use a file to smooth it out.

Of course, that trick was used if you didn't have a hole punch. I
suspect those hole punches would work on plastic too, if you were
lucky enough to have one of the right size.

Michael VE2BVW




Hmmm.... just had a thought... since I am only working with the
inexpensive plastic covers for electrical boxes, I'll just use an extra
outlet cover I have on had for testing. I have both a nibler tool, and
a Greelee chassis punch. Could use the chassis hole punch to just create
a large hole and file out the corners for square, I suppose. Will try
later today.


Ed