Gluing the bridge is an important step, and the bridge must be clamped properly while the glue is hardening to have a good grip. That is done either with a special bridge-clamp clamping through the string holes (which I don't have) or with C-clamps, which I haven't found around. So there's room for improvisation. After checking how people make their home-made bridge clamps, I have found three designs which I particularly like.
One from Ben Crowe of
Crimson Guitars, simple and mostly wood-based, and
another one from Jack Houweling, which is based around some wood extending the arms of a quick-grip clamp, and
the last one, based around a bent piece of metal, from Rattlecan Guitar Restorations. Although I like Ben's one, I don't have Mahogany and Maple (or too much hardwood at all), I only have some black locust/false acacia/robinia pseudoacacia, which might be good enough as a replacement.
An additional complication is that the bridge I have is an over-sized one, being 19 cm width, so the support under the top must be at least that size for the clamp. That is a huge piece of wood to introduce through the soundhole, and if it's mounted to the side of the clamp, than it won't fit.
So, it was time for me to get creative.
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| The bridge clamp idea |
Fun fact: recently one of our toilet roll holders broke off. I didn't throw it away, and it just popped into my mind, that it resembles the bent metal piece from the Rattlecan bridge clamp. I checked the length, and it extends a bit further down the body then where the bridge will be glued, so it could be a good fit for a clamp, but the top side of it was too short. Easy-to-fix, extended it with a nice and strong long screw. The whole thing is strong enough, I can't really bend it, so it will be the base of the bridge clamp.
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| The bridge clamp accessories |
For the underside I have cut a piece of wood to approximately the size of the bridge (20cm x 5cm), about twice as thick as the bent pipe used for the toilet paper holder. Drilled two "vertical" holes from top to bottom, and a horizontal one through the wood, where the toilet paper holder will be fixed, to push it upwards, to support the guitar to under the bridge.
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| The two wood slices |
As the piece of wood mounted on the toilet paper holder can't be introduced in the body through the sound-hole, but both pieces separately can, I have sliced the wood in two in the middle, so that I can "assemble" it, and fix the holder between the two pieces inside the guitar, using two screws, through the soundhole.
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| Partially assembled clamp |
The screws being a bit higher than the surface of the wood, I have cut another piece of wood from some leftover 4mm thick spruce, drilled the holes to reach for the screws, and glued the piece to the top.
The top part was made out of another block of wood, with four holes for the four clamping screws, and one hole horizontally to mount the thing to the rest of the clamp. The bottoms of the vertical holes are countersank to fit the nuts inside. By screwing in the bolts the bolts are pushing the top part upwards, but that part is held in place by the arc of the pipe.
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| First test-fit of the bridge clamp |
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| Second test-fit, with a smaller pushing block |
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| Insider shot to check bottom part |
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| Close-up to check clamped bridge |
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