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All is not well with #3.

Tonight I noticed there is a split in the soundboard, which has only just appeared. It was definitely not there 2 nights ago !! The box has been closed up for approx 5 weeks and the soundboard had been in the workshop for about 12 months before that. I do not have a humidity controlled environment, but I am not at all convinced that this is due to humidity changes anyway. Prior to joining the top, there was a split in one of the plates, roughly along the same line as where this has appeared. When I traced the position of the top on the plates I made sure that I cleared the split piece by at least 1 cm - but maybe there was a structural fault along this line.

Anyway - the split is currently very thin - but who knows what will happen from here. It runs for about 4 cm - from near the heel block through to around where the lower of the two tone bars crosses. When you tap on the guitar you hear no difference in sound around where the split is.

Is there anything I can do about this - or is it firewood !! Would CA glue be any use - I guess the issue of staining would be a problem. It would be very hard to get a patch on the inside due to the position - and I am not sure what effect that would have anyway.

I'm totally pissed at the moment - as the guitar was coming along nicely - but I guess this is what we learn from huh !!

Any advice would be greatly appreciated.

Dave, did you mean the butt block? (when you say it reaches the tone bars).
If it's a tight crack, wet it with an fine artist brush.....just enough to seep into the crack and then work in white PVA glue with your fingers. Using several pieces of masking tape, tape over the crack (across the grain, pulling it together). The wetting will swell the wood and help close up that crack when it dries. Remember to peel the tape off at an angle to avoid lifting wood fibres. All going well, the crack should have virtually disappeared

It sounds like the lack of humidity control could be a contributing factor.

Fingers crossed,
Bill

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If its a hair line crack push on the crack from the inside to open it up a little, then rub some glue (not CA) deep into the crack. After that clamp a caul to the face to keep both sides of the crack level, then squeeze it shut with a clamp.
if i still dosnt want to close, you could try cutting a V shaped groove along the crack, then glue a matching homemade toothpick into the slot.

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tis crack will close quickly if you just bring the RH up. A trick I have done is to carfull place a small tupaware bowl with a wet rag inside the guitar and put the guitar inside a large space bag (do not suck the air out). check it regularly to see if the crack has closed. as soon as it has rub in some hide glue and support with a glue proof caul inside. I use a 1/4" UHMW caul sanded to the dome radii with rare earth magnet under it and I use a rare earth magnet in a UHMW container (cleat plastic) on the outside to locate the caul.

Hey guys - thanks very much for the replies. It certainly sounds like this is fixable.

I will try re-humidifying the guitar as suggested, and putting a small cleat or two on the inside.

Thanks again for sharing your expertise !!

Dave

You really need to monitor humidity. If the top was braced and glued to the rims with high humidity it will crack again..........somewhere else if the repair is strong. If it cracked now because the humidity is too low.......well that's another reason to monitor and control it.
I've got a big humidifier, and de humidifier in my shop. I keep the humidity between 40 and 45% anytime I'll be gluing wood pieces together.

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Um dave,

There be lots of things you can do about this...
run around nakid out side waving the guitar about like a club is one of the millions of things you can be doing about this.

However it won't fix the crack.

Yes is true you can repalce the top and ignite the old one....but me suggest you listen to the words of widom that Michale Payne dude layed down.

Now the only reason me responding to this post is to exthole the virtues of "HIDE GLUE"
Is like a lotta dudes lay down methods and techniques here but few give the reasons why.

Yup, nobody gave you the reason for fixin this way or that.. Just made suggestions...and all will work ...some better than others. Following directions with out any understanding is a mindless wast of time... if thats your thing...join the army.

Now the reason to use HOT hide glue is real simple...it has a strong tendency to pull the gluing surfaces together. Bet you real happy to hear that line.

So follow Michaels babbling and fix it. Then listen to everybody else and learn.

Gee me 63...been building sinse me 16...just had a rib crack open up on me...my fault but me learn.

SO learn...that what we here to do. Learn.



blessings
the
Padma

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