Main diagonal X brace drllied through at bridge - repair or leave?

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I have an Alvarez-Yairi DY-87 doubleneck acoustic which a previous owner had electrified, badly. In pulling out the old electronics I discovered they had drilled a 3/8" hole vertcally down through the bridge and right through the main X brace. Right through the entire depth of the brace and perhaps 3/4 of its width. It doesn't seem to have caused any greater problems yet but that brace is severely compromised and should be fixed, I think?

How to go about repairing? I was thinking of using slow set epoxy and a suitable dowel tapped in to fill the hole? Is there a better way?

[H165]

You'll have to sister the brace on the undamaged side of the drilled brace. Filling the hole will not add strength where it's been lost.

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Originally Posted by H165

You'll have to sister the brace on the undamaged side of the drilled brace. Filling the hole will not add strength where it's been lost.

Thanks could you explain "sister the brace"? You mean like a splint brace on the side?

[redir]

Leave it. If it's a clean hole right through the brace it won't affect the strength that much. If it's chipped out the side, I'd probably still suggest leaving it depending on how bad, then sister it as mentioned.

Sistering is simply gluing in a length of spruce maybe 3/32nd inch or so thick and probably at least one inch in length on each side of the damaged area, so about 2.5in in length. The graft would be the same height of the brace and glued across the damaged area.

I've seen this on many guitars that have very tight x-brace angles.

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Originally Posted by redir

Leave it. If it's a clean hole right through the brace it won't affect the strength that much. If it's chipped out the side, I'd probably still suggest leaving it depending on how bad, then sister it as mentioned.

Sistering is simply gluing in a length of spruce maybe 3/32nd inch or so thick and probably at least one inch in length on each side of the damaged area, so about 2.5in in length. The graft would be the same height of the brace and glued across the damaged area.

I've seen this on many guitars that have very tight x-brace angles.

Thanks! I think i will do both the dowel and the brace sistering. Clamping wil be fun.

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I just finished the repair using the "dowel the hole plus sister bracing splints" technique. And it's not coming apart again without being drilled out.

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Removing and repairing damage from the bad old electrification in prep for new electronics. Drilled out and dowelled old piezos,, inlaid abalone to make them pretty. Epoxy putty filled old vol knob hole, and sanded & stained. Added inside cleat splint "sister" bracing where they had drilled right through main X brace. Also replacing bridge pins with a matching set.
This isn't my original, too scared, bought another to do this to.

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Yeah the splints could be aligned better around the hole, and everything could be cleaner, but believe me, it's hard to get hands holding parts with fresh glue into just the right spots without getting everything coated in glue slime. Is what it is.