A crack around the lower octave pip. I was of course disappointed, but not too surprised by it. The instrument has sat unused for a long time and was all of a sudden getting played daily. Furthermore, this area is especially prone to cracking because 1) the top of any wooden instrument is where you'll most likely find cracks due to the huge amount of warm air and moisture that passes through the top of the bore, 2) the octave pip is a large piece of metal that doesn't expand and contract at the same rate as the wood, and 3) the hole for the octave pip is pretty large compared to the total circumference of the joint, so it creates a relatively large weak spot.
I discovered it only a few hours before a show, so I quickly filled the crack to stop it from leaking that night, then repaired it properly the next day. You can see in the first picture that I had to scrape away the temporary filler to clean it for the actual repair.
The crack was over an inch long, and cracks of that size are often repaired through pinning. The traditional method of pinning involves drilling holes across the crack at an angle, then inserting a threaded steel rod. The pin prevents the crack from being able to expand and contract, so ideally it will be stabilized and unable to grow. The crack is then filled, usually with a mix of superglue and wood dust. That's how I've done pinning in the past, and how a lot of people still do. It's still a very popular and perfectly viable method. However this time I wanted to try a new technique I recently read about, one that's been popularized by Julian Dale Barton, a technician from the Washington DC area. In his "JDB Method," an unthreaded carbon fiber rod is substituted for the steel rod. The procedure is quicker, the cleanup is a little easier, and since the rod doesn't actually get "screwed" in, there's less wood displaced. Otherwise, the process is largely similar.
You start by drilling the holes. They must be drilled at an angle to the crack, as that's what prevents the wood from being able to move once the rod is installed. I did two holes above the pip hole and two below. As you can see, it's a pretty invasive process.
Next the correct size carbon rod is dry fitted, and notched so that it can be broken off at the correct length after insertion.
The rods are installed and glued in place.
Then the ends are filed and smoothed so they don't protrude. The crack is also filled and dressed to hide it and add a little more stability.
After sanding the surrounding area a little bit and applying oil, this is how I left it for a few days while I was finishing up my recent gigs. The functional part of the repair is done at this point, and all that remains is cosmetic work.
A few days later I was able to clean things up and hide the pins. I started by grinding down the ends.
Then filled them with wood dust and glue.
Next is where the real art and finesse comes in to a repair like this. You want to blend things in so they're invisible, or at least redirect the eye so that no one would ever look for evidence of a repair. The result is below. If you look closely enough, you can see evidence of one of the pins, but otherwise they blended in almost perfectly.
Having all the keys on helps divert the eye, too, because there's so much stuff up there that a lot of the wood is covered up by nice eye-catching silver. Thanks silver!
Next project - replacing the octave levers and doing away with that silly automatic mechanism.
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