So, I am NOT trying to do a full restoration here - it's a 50's Martin uke, and it's a nice instrument, but at best it's a $500 instrument in mint condition, and given that a dog decided to use it as a chew toy while it was in a soft case, this will NEVER be in mint condition.
I posted about this before, when it was in much worse shape. Since then, I have managed to get some repro keystone tuners and drill them ou to replace the shrunken tunings knobs, I've glued of all the cracks and reglued the loose back brace, and I've managed to piece together the four splinters I did have for the soundhole. It's looking a lot better, and it is getting close.
There is sill a big chunk of wood missing from the front. It's quite the gash. I do plan on chiseling out a bbit to make a more even and workable space, but I'm not sure how I want to accomplish this. I suppose I could fire up a router with a dovetail bit and just make an inlay piece that way as well, but that seems difficult given the limited region I have to work in this instrument. I can do the chisel out a hole/chisel a piece to fit the hole/use carbon paper to figure it all out method, but I'm not sure what shape I want to make.
I am certain that there will need to be some reinforcement all around the soundhole - there were at least five cracked and slipped pieces, as well as the splinters I had to put in. I also need to find a chunk of the rosette, or form my own.
Any thoughts on filling that gaping hole?
Since it's never gonna be a mint-condition uke, one thought that occurred to me was to do a straight structural repair on the hole and the appearance be damned...because you could cover it with a little pickguard! Scale-down a regular tortoise shell pickguard to be size-appropriate and there ya' go.
Other than that, cutting-in a football shaped mahogany patch wouldn't be a bad thing. I wouldn't take any great pains trying to hide it, as the "dog ate my homework" story makes for a great conversation piece!
Oooh! Oooh! THEN I DON'T HAVE TO FIX THE MISSING SOUNDHOLE INLAY!!! I really like this idea, since trying to fix that ring was going to be a nightmare at best, and likely would have just busted stuff up again.
This should be fun - this is a keeper, just for my own use, so I'm looking forward to having the great Martin uke experience at a GREATLY reduced cost - I'm just glad it wasn't my uke and my dog when the damage happened.
This also points out one more fault with those naugahyde soft cases - they are great chew toys. And it points out how well Martin built these ukes - I mean, I love Kamaka ukes, but if a dog did that to a Kamaka, it would be truly ruined.
I'm just going to leave the various bite marks and scratches as conversation pieces. I've stabilized the punctures on the side with hide glue, so they aren't going anywhere.
Thanks again! I'll post the results.
Mike's pickguard cover-up is a great idea (hope you are right-handed).
Underneath that you will need to repair the structure of the top with a patch - presumably mahogany. Cutting the defect to a regular shape like a long oval will allow you yo match the patch to the hole better. It will need some reinforcement on the inside to cross the defect (e.g. a light spruce patch or popsicle braces). You might want to do the bit that enters into the soundhole as a separate patch - or all in one, I'm not sure. I am sure that you can come up with something that is pretty solid, and then slat that pickguard over the mess!
Definitely do not use a router.
Just use a good sharp exacto knife to put a 45 degree taper to the hole, I wouldn't change the shape of the hole. Next get an accurate tracing of the tapered hole, by placing a piece of paper over the hole and rubbing the edge with a soft lead pencil. Now place tracing on mahogany piece, about the same thickness as the top or a few thousands thicker, so you got enough material to sand it down some.
Once piece is rough cut out sand and scrape, checking fit as you are doing this. Once you get the best fit you can, glue and clamp in place. I'd leave it a little larger at the soundhole, then you can recut to proper diameter once the glue is dry.I'd just make a pencil line semi-circle on the repair and cut to the line with a rasp and sandpaper.
Once sanded smooth you will need to stain with dark mahogany stain to match the rest of the instrument. Then I'd wipe or brush on shellac as a finish.
You'll have an area with no rosette, but if you are real meticulous you could possible route a channel an piece in a section. Personally I wouldn't worry about that. You will always see the repair, but at least it will look fairly good, structurally fine, and playable.