JSA Cigar Box Guitar S4 – Homemade Plexiglass Pickguards and Cavity Plates

I’m working on a modification for this guitar that necessitates that I drill a hole in the cavity plate, so I decided to make a substitute to keep from damaging the original—because to be frank, where am I going to find a replacement cavity plate for a DeArmond?

I didn’t have a Dremel and didn’t really know how to cut or shape plexiglass, but I found an 8″ x 10″ piece for $4.00, so I was ready to rock. After feeling my way through fabricating the main cavity plate, I decided to make a toggle switch cavity plate as well…

I had the original, so I removed the protective plastic from one side and placed it as close to the edges as possible. Then, I traced it in Sharpie.

Quick research uncovered that I need only cut around the shape with a razor blade. After etching a circle about a 16th of an inch outside of the Sharpie outline, I flipped the blade backward and traced the etched circle two more times.

I removed the protective plastic from the bottom and then used a pair of small needle-nose pliers to break off the outer material, in small pieces, leaving a rough circle.

Using a small bench grinder, I removed the material in an even, circular motion up to the Sharpie outline. Then, placed the cover in the hole to check for proper fit and went back to the grinder for small adjustments. In absence of a grinder, files or sandpaper could be used, but it would require multiple grits and a lot of time.

Once the cover fit, I marked the holes in Sharpie and carefully drilled the holes. Then, I switched to a larger bit to countersink the hole.

I cleaned up the edges with some 220 sandpaper and then installed it.

This same method can be used to make pickguards or switch plates and the plates and guards can be painted or otherwise decorated on the bottom if desired.

See…now I have my 7-pin jack installed and I’m ready to complete the modification without destroying the original plate. As a word of caution, you’ll notice that the plate broke on the screw hole to the right—be careful when drilling your recess hole and don’t over-tighten the screws.

Thanks,

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