hands on look body binding decary prevalent time want better understanding mystery diagnoses shrinkage final crack immense tension

Replacing original Tortoiseshell binding that''s decayed naturally over time.

Greetings, “Restoring an Original” readers. Each month I strive to bring you something new and refreshing, with a hands-on look into the restorations on our benches at BGF. This month, we’re taking a closer look at a Gibson J-50 that came out of Gibson’s Kalamazoo, Michigan, factory in 1974. Our client was very concerned about the body binding decay that was prevalent for some time and wanted to get a better understanding of the mystery behind it all.

Clearly, this was not a classic case of celluloid binding shrinkage finally cracking to relieve the immense amount of tension it had come under. Visually, this body binding had a decaying rash of self-destruction from the inside out. One might think that it came from those elements that are very bad for your guitar: extreme heat or cold, high humidity (wetness), low humidity (dryness), harsh cleaning agents, bug sprays, heavy body oil, and acid. Other elements, like smoke and sunlight, will change the appearance of some finishes as well.

The above elements may have contributed to promoting the inevitable, but in fact it’s all about the chemical makeup of this binding. Perhaps you may have already guessed it. We were dealing with original tortoise binding, which self-destructs as the plastic binders start to age. Some know it as binding rot. Do not mistake this as an issue of environmental surroundings—though it is true that warm temperatures may speed up the decaying process, while coldness slows it down. The back and top body binding clearly could not be saved. It needed to be removed and rebuilt with a more reliable and stable material. I have seen tortoise pickguards on archtop guitars begin to decay right where the support block was glued. Solvents give off gases, which leach out and cause destruction. Clearly, original tortoise does not like acetone or any other gluing solvents that were used during that period.

Binding Removal
Fortunately, this guitar was already scheduled for a neck reset, as it measured very high in playing action even with the neck straight and the saddle bottomed out. So the neck was removed not only for the reset, but also for rebinding the top and back correctly. Tools I used for the binding removal were a hair dryer, a channel spatula, a Sloane Purfling Cutter (StewMac # 0354), and the ShopStand and Guitar Repair Vise (StewMac # 5391).

When removing binding, it’s important to do so in a controlled manner. The body was not going to be stripped and given a full re-spray, so I wanted to keep things looking really clean and crisp—because there was only going to be a thin layer of nitrocellulose airbrushed over the replaced binding once everything was trimmed and groomed.

Using the Sloane Purfling Cutter.

Using a hair dryer and channel spatula to remove the binding.
I used my Sloane Purfling Cutter to lightly score the sides of the ribs at the outside edge of the tortoise binding from one end to the other. The same was done on the top and back of the outside edge of the white/ black/white purfling. Even though the Sloane Purfling Cutter is marketed as a violin tool, it becomes the perfect tool for removing defective binding on guitars after a slight modification with a longer hex head screw.

I used the hair dryer to lightly warm up the binding and glues while I cautiously pulled on one end of the binding. Running a channel spatula against the ledge works well whenever the binding to body joint gets hung up—I trimmed down a previously purchased spatula to the size of the binding and purfling channels. I progressed slowly, inch by inch, at times going back and repeating the first step by re-scoring small sections using the Sloane Purfling Cutter. Doing it this way helped avoid any tear-out of precious wood and kept the lacquered finish line looking very clean.

Some of my go-to places for binding and other plastic resources are Stewart- MacDonald (stewmac.com) and Luthiers Mercantile International (lmii.com). If you’re looking for specialty and hard-to-find materials or shapes, also check out Pickguard Heaven (pickguardheaven.com). Stay tuned for next month, when we’ll be sizing, bending, and gluing the laminated purfling and binding into the pre-existing routed channels on this ’74 Gibson J-50.

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