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lefty dan
09-19-2011, 03:03 PM
Hi,
So I’ve built some ukes but never repaired any. ( other than my screw ups ).
I was at the music store today and got a Kamaka soprano uke. I think its from the sixties. Sounds good, plays good, but has a crack down the back. Its from top to bottom. Right where the two halfs are joined. Its not a crack, more of the two half’s came unglued and needs to be re glued.
Because of the separation I was thinking of a small strip of wood or trying to re hydrate it by keeping it near the shower for a while. Truth is I have no idea how to repair it but want to do it myself.

Please give me some suggestions from my Luthier friends.

Thanks in advance.

Lefty Dan

Rick Turner
09-19-2011, 03:14 PM
The only problem with the rehydration thing is what happens when it dries out again.

Is there a center seam reinforcement strip inside? If not, I'd probably glue it with HHG, clamp across the back and then try to put in some cross grain center seam reinforcements while the back was still in clamps. With HHG, you can do a "rubbed glue joint" with the patches. You may have to get them in some clever way, but it's doable. Yes, you could also glue in a cleat or even set up a fixture and rout a clean narrow channel down the back and inlay a strip of purfling or marquetry. It'll still need some reinforcement on the inside. And you'll have to deal with finish touchup on the outside. All possible and not all that big of a deal, really.

lefty dan
09-19-2011, 05:33 PM
Thanks Rick.
I was thinking about a reinforcement strip on the inside but it would take some maneuvering to get it inside. Eather way I played it tonight with my wife for about an hour and it sounds good and is fun.

Please keep the suggestions coming.
Dano

olgoat52
09-19-2011, 06:33 PM
Rick pretty much gave you the three options.
-Full center strip
-Diamond cleats
-Route with new enter strip with backing strip or cleats.

If the crack is still really visible after rehydration and cleating it may be necessary to route and put in a binding strip or cut a "V" groove the length of the crack and glue in a triangle shaped strip of Koa. The V groove works ok for shorter cracks but if it is the whole length of the body, the strip might be the better bet. Cleating should stabilize it. The strip or V groove bit is mostly cosmetics.



Thanks Rick.
I was thinking about a reinforcement strip on the inside but it would take some maneuvering to get it inside. Eather way I played it tonight with my wife for about an hour and it sounds good and is fun.

Please keep the suggestions coming.
Dano

Allen
09-19-2011, 08:39 PM
Just as Rick said. And he would know. Done more of this than any of us.

Pukulele Pete
09-20-2011, 12:33 AM
Go to Frets.com and you will find info on fixing cracks. I've fixed a few and I used small rare earth magnets as clamps. Worked out good for me.

lefty dan
09-20-2011, 05:00 AM
Thanks guys,
I will go to Frets.com and check it out. Most likely do a center stip like Rick and others said. I will post to let you know how it turns out.

Dano

lefty dan
09-20-2011, 05:32 AM
Frets.com calls my crack a seam separation. I think I will do the center strip. But can I or should I try to re hydrate the uke. I don’t have anything to use to do it. Can I put it in the bath room while showering??
Dumb questions but I just don’t know and want to do it correct.
Dano

Rick Turner
09-20-2011, 05:46 AM
As I said, hydrating is temporary. If the uke then goes back to it's normal lower humidity environment, a seam or crack may just open up again. Hydrating only really works with instruments that have gotten way too dry...old attics for years, trunk of a car in the sun, etc. Then there's a shot at bringing it back up to normal ambient and having it stay right, but I don't trust it.

lefty dan
09-20-2011, 01:29 PM
O.K. today I put a center strip down the seam. It appears to be working. I noted one turner broken. I replaced the tuners and cleaned up the uke. Put some good strings on it and wow.
Please dont hate me for this but I gotta have a strap on my ukes. Gotta get a strap button and put it on.

Thanks for the help. Again why I love this place.

Dano

RyanMFT
09-20-2011, 01:46 PM
Glad to hear the strip is working and the uke is brought back to life!

How about some pictures?

lefty dan
09-20-2011, 07:32 PM
282482824728246Just got back from an open mic here in Morgan Hill. I played some guitar and some uke. It was fun because I got to try out the new old Kamaka. It worked great and Im very happy with it. I havent taken any close ups of the uke yet.
Great. Bought it yesterday. Fixed it today and played it at open mic tonight.
I was lucky to have Mark join me on harmonica, he is one heck of a harmonica player.
Thanks

Dano