Official Luthiers Forum!

I’m currently repairing a rare, wide nutted Takamine OM that’s had some damage from a car crash. The back braces have all come partially loose from the back with the main back brace, the biggest one, deepest in the body, cracked in half.
The fingerboard extension along the neck also caved into the body via the tension generated and I’m doing the repair now. I have a few basic questions I’d appreciate your educated answers to:

-In repairing the cracked brace, since I don't have a dishing sander, can I carve a long V along the top of the brace and glue the original into a usable new one?

-On the figerboard extension. Do I brace the area with cross grain wood, for stiffness, or along the grain to reinforce the top, yet still allow for some flexion, for sound purposes.
- Do I glue the wood patches to the top only, or also to the sides of the neck block and little stiffener pieces already there?

Thanks very much, for your help.

My opinions: Time for more information than what's been provided. Is this OP's property, or is someone else's? What's the expectation of the owner as to satisfaction with what results? I don't think (m)any of us could analyze the problem(s) and offer a path to success.

_________________
Peter Havriluk

Peter,
Thank you for taking the time to respond. I’m not sure why what you’ve asked matters but, the guitar belongs to a friend and the expectation is that the guitar again be playable but not exactly a treatise to perfection.

The damage is fairly bad, though not as bad as it may sound. I’ve already stabilized the top cracks via strings of humidification and lining up the neck and top within a 256th of an inch to perfect (or possibly better) via clamped Titebond gluing. The neck angle reads a touch too low right now but I haven’t yet tackled the back braces, save for removing the broken one. I expect the neck angle to return to perfect once I’ve properly replaced the main brace and reglued the two loose ones.

Thank you again for any ideas you might offer.

If the back brace split in a fairly long break, I would reglue it and after drying if it seems reasonably sound I would reuse it as is.
I'm assuming the soundboard split either side of the fingerboard and that is what you have glued up and now want to reinforce. I would make a "popsicle" brace and install it across the upper bout area in a cross grain fashion. That would add strength in a relatively acoustically dead area.

Clay S.,
Thx for your ideas. The main back brace split in an almost perfectly perpendicular fashion at close to the very center, where a small channel had been cut for the back center lining strip. It was on the upper bout corner of that channel going straight up.

The top pulled towards the bridge under string tension and had deformed slightly at both the top purfling and the soundhole rosette, but I’ve managed to get that stably, very close to perfect now. I’m putting fitted cleats wherever I can along the upper guitar bracing (thankfully the Takamine has a preamp hole a right next to where the neck block is glued in and I have ready acces to the upper bout side for measuring and clamping cleats) and I’m fitting them as tightly as I can btwn the popsicle brace that’s really just a little stiffener bar, much like the soundhole reinforcement bars are.
I will though, take your advice and mount a long crossbrace at the very front of the soundhole. Thank you for the info and the help.

If the back brace snapped in half perpendicular to itself I would just make a new one, shaping it similar to the old one. I wouldn't try to repair it.
Cleating the cracks along side the fingerboard should work, but I would be inclined to remove the "little stiffener bar" and replace it with a more substantial popsicle brace. But if you have already cleated it I wouldn't change it - cleats should work fine.

Beware that the cracks alongside the fingerboard may indicate some serious damage in region of the upper transverse brace or the the neck block. The alignment might look OK now - but I assume you have the strings off? Under string tension the whole neck block can roll forward if the structure is disrupted. Maybe it is all OK - but what you are describing sounds like a red flag. Try pushing the neck forward, really lean on it. Does anything move?
Have a look at this tutorial by Frank Ford and see if any of this might be going on with your patient.
http://www.frets.com/FretsPages/Luthier ... crack.html

Mark Mc,

Thank you so much for that link! This is very close to what’s happened to this guitar, though Ford’s example is quite a bit worse. The damage on this Takamine was caught more quickly and string tension taken off completely. Checking the glue with a feeler gauge seems to tell that the glued braces, though there was some movement, which left some few tiny small areas of white squeeze out, had stretched but held tight on all of the top braces and the reinforcement bars. Can’t get cleanly underneath them.
I will do the test you’ve suggested and rethink my approach some, based on what I’m seeing in this Frets.com article, which is just great to have. Thx again.

Yep - it is worth reading just about everything Frank has put on those pages if you are interested in guitar repair or building.

That Taka sounds seriously injured. The neck and fingerboard got forced forward far enough to snap the top and disrupt the bindings and rosette. That can only happen if the neck block and UTB have let go. In other words you are seeing bruising on the skin that indicate that the bones are broken underneath. If so, it requires major surgery. If done by a professional it will cost way more than that guitar is worth. If not done by a professional the repair will probably fail. Sorry, I don’t want to besmirch your abilities as a repairer - but I certainly would not consider myself capable of doing such a job. By all means have a go if your friend agrees - but I think the best course of action might be to include the death of a guitar in the insurance claim for that car accident, and buy a new one. Sorry for the pessimism.........

Danny - On reflection, I think I came on a bit strong with the negative prognosis in that last post. I can't tell what is going on with that instrument without seeing it. And I am not a repair expert - just a guy who builds a few guitars and hangs around forums where I read the experience and opinions of people who actually do repairs for a living. So please take my suggestions as a worst case scenario and then make your own assessment.

to get the best advice post some pictures.
as a 20 yr experienced repair person I have put some disasters back together. We need pics as we can't access the damage without them. So get that info and we can get you the best techniques for a particular repair.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Mark Mc,
I take no ill will from what you’ve said and I truly appreciate the help you’ve given me. I had thought that I was going to cleat the cracks all around and that would’ve been sufficient, but now I’m going for a full brace to work out n conjunction with the forward transverse brace that’s already there. Thx for that.

I do fully intend to do this repair and leave a functionally stable guitar as the end result and should my first efforts not achieve that, I’ll keep going until I have that result. Nothing wrong with learning by fire. As for the guitar itself, it’s actually a fairly valuable thing, sells for around $1k used typically and it’s worth the effort (it’s quite a fun guitar to play, or it was....).

Anyway, I’m already in it and it’s going to take some discipline to make it whole but patience and discipline are the reason I asked for advice here in the first place. Thx for forthrightly answering my call for help. I appreciate it greatly.

John Hall,

I’ll post some photos later on today. The camera in this phone doesnt work well, I cracked the glass filter, so I’ll post from my old phone when I get back to working on the project this afternoon.

Thank you for taking the time.

Here are a few photos, More coming,

Sorry about the size but it does seem to be useful

Here are a few more photos, these will be smaller I believe:

https://imgur.com/a/VWS1frp

Not your typical OM. Being a cutaway and with the neck block extension almost extending to the brace, a cleat on either side may be the only practical reinforcement you can add. You -might- be able to double up the brace above the soundhole, but that may not be necessary. The guitar failed from trauma, not from inherent structural failure. Adding the cleats may restore it to it's original strength.

It now looks pretty straight. If the only damage ( beyond the back braces) was to the soundboard, and you have now realigned it and cleated it, then it might be all good. The main issue is to see if there is internal structural damage to the top braces and the neck block’s attachment to its supports. I suggest testing all of the joints of the top braces and around the neck block with a thin probe like a feeler gauge or a piece of stiff card. Also stress the neck joint to see if it is completely stable. If all looks good it may be OK, but the proof will then be in how it behaves under string tension.

Thanks Clay and Mark.

Some digging produced this link:

http://www.frets.com/FretsPages/Luthier ... rack2.html

Which has really focused my process now. I’ve ordered some braces from stewmac and plan to redo the one I’m making (in big photo one) as well as the replacement back brace. Two concerns though

- in the link above, Ford has installed a nearly identical neck block reinforcement cleat but he’s firmly glued it to the block itself. Should I redo mine ( in big pic 2,3 and 4) to match, and use hide glue as he infers would be the better choice (or the epoxy he uses)?

- in the last big pic, you can see a big chip in the kerf from where the neck block moved forward. If I install a cleat between the neck block and transverse brace, it obviously won’t be able to move forward again. Is that enough, along with the new dbled transverse brace I’m also making?

Thx all for the advice.

Oh and do I need to mount the new tranverse dbl brace into the kerfing on either side too?

Any help and/or educated opinions on those last three questions will help me greatly. I came here looking for some professional guidance and I’m not sure what y’all might need from me to better suss this out. Whatever it is, I’m ready to do it....