Koa top & bridge footprint remediation

[onewent]

Greetings, all .. I'm seeking some advice from those who are familiar with remediating bridge footprints that experienced a lot of grain 'pull put' upon bridge removal. Although I've done this task a good number of times, successfully, I've never worked on a koa top before. As you all likely know, koa is pretty 'chippy' wood, hence the grain pull out.

I've already added more heat to the bridge and tried to peel off the chips that remained on the bridge, and I've got one off do far, but it's tedious and not always 100% successful. I'm going to try for the rest of them, too. If I'm not satisfied with the results (it's a skimpy 'mustache' bridge, not much gluing surface) I'll look to route a 64th or so, and inlay fresh wood. One certain thing about this repair, the bridge/top contact surface needs to be 100%, or at least as close as possible to that, to ensure no bridge flying off in the future!

First question, since I don't have any koa, would mahogany substitute ok?

And, would it be viable to route to the depth of the deepest divot, and just inlay the bridge into the top? I'll need to make a new bridge, since the original is cracked and re-glued.

Thanks!
Tom

[onewent]

[Taffy Evans]

Hi, in similar top/bridge repairs like this, I have routed out the damaged area and inlaid spruce or cedar first, leaving as much of the original top material as possible then replaced the bridge in the normal way. In your case I would route the main bridge area only as the wings are more decorative than functional I would think. If the top has a radius it may make it a bit more challenging.

Im not sure what would be a suitable veneer to fill the recess in the Koa.

Cheers Taff

[George Roberts]

When I needed a small amount of koa to repair a uke fingerboard, I was able to find some inexpensive knife "scales" from knife making supply firms.  "Scales" are the wooden handles on either side of the blade.

George

[onewent]

Taffy, thanks for your input, I'm planning to route just under the main part of the bridge and clean up the wings as best as possible.  Problem is, the glue used for a prior 'reglue' is not water soluble, which was another 'push' to route/inlay since I use hide glue in my repairs.

George, thanks for that tip.  I've not heard from anyone re mahogany as a substitute for the routed koa, but I'm thinking that it will be ok, and sourcing koa is probably not too much of a problem, but koa is so brittle that I believe it wouldn't be the best choice for this repair.

Thoughts?

Tom