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Really, it's just a little thing
Replacing a Chip at the Sound Hole Edge
© Frank Ford,10/30/01; Photos by FF
Not wanting the eventual Clarence White look, the owner of this D-28 decided to have me fill in the missing piece. It's too bad the little chip couldn't be found after the accident, because that would have made the job quite a bit easier. | |
The area near the chip was severely dented by the falling microphone, so I used my soldering pencil and a bit of wet paper towel to generate some steam to allow the wood fibers to swell back to their original shape (or close to it). | |
How about some nice clear hide glue for the cracks in the area? It's the stuff that won't discolor wood, so I used some thinned out (50%) hot hide glue to run into the tiny cracks. | |
It took a battery of tiny clamps to level things up because there were some missing flakes of spruce underneath where the bottom surface wasn't quite even. | |
I made a little spruce reinforcement plate for underneath, to stabilize the repaired cracks, and to provide a "bed" for my new little patch. | |
More hide glue, of course. | |
After rummaging a while in my scrap drawer, I came up with a piece of spruce top wood that had grain to match the missing piece. | |
I cut a chunk out and glued it in place, making sure the sides fit tightly, but not worrying about the inside soundhole edge or the portion where the rings would be cut. I'd be cutting those areas later anyway. | |
Trimming the patch level with a chisel. I glide the flat bevel of the chisel right on the finished surface and the sharp edge slices off anything that sticks above. | |
I beveled the inside edge of my reinforcement patch to about 45 degrees so it wouldn't be visible after the repair was completed. | |
Looking around the shop I found a perfect sanding block to true up that inside edge. | |
Now for the missing ring channel. This is the L.M.I. purfling channel cutter. I've owned a couple of traditional German violin purfling cutters but I like this one much better! | |
I only had to cut the inner edge of the channel because the back edge was still in good shape. The unwanted pieces of my new patch chipped out easily once I made the cut. | |
I have a bunch of laminated binding and purfling bits around the shop from salvage, but I couldn't find any piece of an old Martin soundhole ring, so I had to use some new pieces I got from Martin. A little observed fact is that Martin has changed the dimensions (slightly) of the black and white soundhole rings. | |
In this case, the white portion was a few thousandths of an inch too thick. It may not seem like much, but it would stick out like the proverbial injured appendage if I used it as is. So, I scraped it a bit until it looked more the right dimension. My little new piece is so short I could get away with hand scraping to true it up. | |
After correcting the dimension, I welded up my little section by coating the plastic with acetone and clamping it in the flat jaws of my trusty Versa Vise. | |
OK, time to glue in the little piece, after trimming it to fit. I chose cyanoacrylate for this operation because it tends not to soften the plastic too much, which might cause the black to "bleed" a bit into the slightly abused old surface of the purfling channel. | |
I tapered the ends of the purfling just a bit so it would be a tight press fit, and used a couple of clamps for insurance against the purfling lifting out before the glue set. | |
Here's the same basic operation for a tiny missing chip. In this case, I tapered the end of a piece of purfling, coated it with cyanoacrylate, and drove it in like a little spike. | |
After the glue was set, I was able to snip off the end of my wedge. Making my patch into a little tight fitting wedge is an easy way to make sure the ends fit tightly at the top for the best appearance. | |
A couple of strokes with a sharp chisel made quick work of leveling the purfling patches. | |
Some orange shellac and a bit of aged amber lacquer simulated the aged appearance of the old material so my new pieces wouldn't stand out too much. |