RadioBanter - Plastic dial cover repair

Mike Coslo wrote: I recently picked up an old radio at a fest. One of its issues is that
the clear plastic cover over the dial is broken...Anyone know of a link, or how to make such a thing?

Mike...

How are your woodshop skills? g and visualization helps here, too.

Part of the problem of old dial covers is the stuff they were made
out of just wasn't meant to last, it gets brittle, develops cracks,
yellows, and bits and pieces of it flake off. If it's intact but
yellowed, a little Brasso (the Wonder Tool, far as I'm concerned) can
get the grime and some of the yellow out, especially if it's been
subjected to the exhalations of tar-based pollutants derived from
cigarettes. koff

One method I've heard of (but have not actually tried meself) is to
remove the old dial cover, carefully measure the dimensions: exterior
depth, length & width, interior depth. HOPEfully it's a standard
rectangular-type cover, but this works for any shape of dial cover.

Have a buddy who's into woodworking (or a student at a local
high-school) built a wooden die-and-form in two pieces, one for the
face-side, and one for the back-side.

The face-side form needs to be wider and longer than the rectangular,
routed, hole in it by, say, three inches either way. And actually you
needn't route a rectangular hole, just find a board that's about as
thick as the outside dimension you need, cut it into four moderately
long pieces and butt them together securely to the correct length and
width; that's faster and easier to adjust as needed, rather than
re-routing another chunk.
Of course, maybe you LOVE your router; well, then route away!

The INside die needs to be just a tad smaller than the Outside form,
maybe 1/16 inch in length and width to accomodate movement of the
plastic into the space. Mount it (glue) onto a suitable backing board
to give you a good surface to push on, perhaps add a handle? of some
kind to give you a better grip.

Test the fit and adjust as needed; should not be snug, though.

Note: you could do it the OTHER way, as well: push the outside form
onto the inside die; this way you can watch as what happens

THEN.. you just need a fairly tough sheet of thin acrylic, 3 mil
thickness, maybe, or thicker.
Maybe a pair of tongs is good to have around at this point as
well...to handle the plastic after heating...

Have the face-form tacked down so that it doesn't move on ya, heat the
acrylic in hot, not necessarily boiling, water, grab it with the
tongs, toss it onto the face form, ram the INside die into the mating
hole, hold for a few seconds (minutes?) while she cools...and VIOLA!

You have a custom-made replacement faceplate for your radio, once you
trim off the excess plastic. Make several, you'll never know when
someone Else will want one.

This is approximately how they did it in-the-day, same as any molded
piece of stuff, and approximately how it might be done. Caveat Routor.

Vinyl or other types of plastic may work as well or better; once you
have the die you can experiment.

Or, instead of doing all this yourself, get the guys in woodshop /
plastics to whip this up for you as an extra-credit project. It ain't
hard, and it's real seat-of-the-pants repair. They might even do it for
free. Maybe.

And, no, I didn't thunk this up all by myself; this was posted in an
old ARCI (Antique Radio Club of Illinois) publication, I think, a LONG
time ago.

Next topic: formulating, compounding, and rolling your own resistors
for fun and profit!!

[NOT! but it does sound like fun....]

73s,
Terry Bakowski, still working on that tech