Repairing Major Bridge Cracks
Source: Guitar Bridge Repairs
Repairing Major Bridge Crack:
Major cracks in the acoustic guitar bridge are easy to spot. They are almost always across the bridge pins, which is the weak point of the bridge wood and they also more than likely started out as a very minor crack that should have been repaired before it got to this stage. See the article on Repair Minor Bridge Cracks for the steps in make that repair.
Quite often coupled with the major cracking problem is a displacement of the bridge from one side of the crack to the other. Usually the back half of the bridge lifts upward, due to the string tension shifting from being distributed over the entire surface of the bridge to the tension being transmitted to the back half of the bridge.
Repairing the Existing Bridge:
Unfortunately, when a bridge is in this state of disrepair, you have no recourse but to replace the bridge with a new one. If you absolutely wish to fix the existing bridge you can try by first lifting the bridge pieces, cleaning the bottom of the bridge and trying to split the bridge entirely in 2 pieces. What you will find is that the 2 half’s do not line up because one was sprung and the other was not.
What I have done already is to hold the sprung half down with screws through the 1/2 bridge pins so that it is flat. Then fit the two half’s together and see how they dry fit. If you are missing too many fibers of wood or you can’t get a good joint – forget it.
If you do get a halfway decent joint, mix up some 2-part Epoxy Glue along with some wood saw dust to match the bridge and apply liberally to the crack.
Fit the halves together and clamp with a couple of clamps. Note that this works best if the workboard that you have the bridge attached to is just a little bit smaller than the bridge footprint.
When the bridge glue is dry, add more glue if the glue has shrunken beneath the surface of the bridge. When dry, sand smooth, re-drill the pin holes and dry fit on the guitar top.
Making a New Bridge:
I would rather find a close wood match for the existing bridge and use the existing bridge as a template to trace the bridge outline, bridge pin locations and transfer the saddle location to the new bridge blank.
Refer to the article on How to Make an Acoustic Guitar Belly Bridge for step by step instructions.
Tags: bridge crack repair, bridge repair, how to make a belly bridge, how to repair a cracked bridge, repairing major bridge cracks
