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I was asked to look at this guitar and assess the damage.

The owner doesn't mind if the repair is not invisible as long as the crack is secured. I thought this was a good thing since the top is stained and the guitar is almost 30 years old... It's a Canadian made 1979 Kamouraska classical with a solid top, back and sides. It was a fairly expensive guitar at the time of purchase.

I haven't had a chance to take the strings off yet to see how well the crack closes.

I was thinking a veneer backing from the inside. My concern is that if the crack doesn't close 100%, I'm going to have to fill the gap with stained epoxy
Any thoughts?





Thanks in advance.

Alain

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I'd like to be able to prove, just for once, that money wouldn't make me happy...

if the crack doesn't close , rather than glop in a load of epoxy, it would be better to insert a splinter.

Humidify the guitar and see what happens, before you do anything else.

Looks like there may be a second crack closer to the waist.

I bet the thing closes. but if not add a splint. Gap filling with epoxy is not a good idea.

Definitely splint it, it can be pretty easy to do and can be almost invisibe. Let me know if you need any help,
Evan

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http://www.NewYorkGuitarRepair.com

I agree with Evan, a crack that large needs a splint.

Tom

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http://www.moriciguitar.com

Is the large appearance of the crack due to separation -- causing a gap -- or is it caused by one side of the wood sort of sitting on top of the wood on the other side of the crack? If the latter, you might be able to close the crack without having a gap. Sometimes, though, with cracks like that, the edges can get "hung up" against themselves, and won't close easily. You might try inserting a thin spatula between the edges and see if you can carefully pry the gap closed, kinda like you would pry a bicycle tire off its rim. If it closes up, then hide glue and cleats should work fine, I would think.

Also, since this is a classical, and assuming that it has the two transverse braces (aka "tonebars") above and below the soundhole, the wood will have had to separate from at least one of the tonebars to do this, probably just the one below the soundhole. You'll need to check this as well, but I'd check both tone bars.

Best,

Michael

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Live to Play, Play to Live

I am no expert at this Alain, but I think little pyramid shaped blocks (small and LIGHT ones) would be better than a veneer, which would, when coupled with glue, tend to dampen the activity of the top, think plywood.

So use little blocks as Michael has suggested with hide glue. Just press them on by hand and hold for about 60 seconds or so and they will bond quite well and will actually pull themselves tighter as the glue dries.

Good luck!

Shane

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Canada

I bet you can close it by adding moisture.

Al

No clue about what you're gonna do Bro but good luck in fixin' this!

Thanks for your help guys.

Indeed, epoxy is a bad idea.

It turns out that the upper transverse bar was unglued. I glued it back using good old titebond. I know I got a good amount in there, I had squeeze out from the cracks on the top.

Once glued in, the crack closed nice and tight. No sliver needed. I added little blocks from inside. These I glued using my very favorite glue in the whole wide world... HHG!!!    

Now I've got the slightest hint of crack when you look across it with low angle light. What would be the best thing to do? Drop fill with CA, scrape, sand and stain?
The owner said I could go nuts as long as it wasn't with the bill...    I would really like that crack to disappear completely. Any thoughts?

Thanks again guys.

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I'd like to be able to prove, just for once, that money wouldn't make me happy...

How about some spruce dust with a few drops of HHG bud?

Good on ya Alain!! The "crack" may just be the finish now. I am not giving advice on the french polish issues so I will leave taht to others. All I know is that it takes skilled people to replecate an aged finsih and make it blend in will. For me it would end up as a nice burst! (YUK!)

Shane

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Canada

[QUOTE=Shane Neifer] Good on ya Alain!! The "crack" may just be the finish now. I am not giving advice on the french polish issues so I will leave taht to others. All I know is that it takes skilled people to replecate an aged finsih and make it blend in will. For me it would end up as a nice burst! (YUK!)

Shane[/QUOTE]

My thoughts exactly, my good man. It will be tricky replicating that stain exactly. I'm still debating what to do at this point... I wonder how the owner feels about bursts!

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I'd like to be able to prove, just for once, that money wouldn't make me happy...

I'm gonna go check with the Doc for...i forgot...oh yeah, Alzheiming, i completely forgot to congratulate you my great friend! So sorry bud!

On another note, how about using that orange shellac on it?

No dust, no epoxy! I agree with others here, humidify the guitar and if it does not close all the way cut a splint and insert. Once this is done, I would glue a few supports over the crack from the inside.

I did a 1960's classical you all may recall a month or so ago, I posted to get some opinions or other methods. It was really not that hard to match the splint color, it just took some time and patience.

Mike
White Oak, Texas

Yes Mike, i remember that guitar and it turned out great too!

Did You glue the crack, or just close it and cleat it. If you can work in some HHG the crack will become much more stable, and less visible.

Al

What Al said. I have also used Titebond-I thinned with a bit of water, and let the crack wick the glue in. That actually works pretty well, I've found. Plus it doesn't overly darken the crack the way CA or dust does.

Also, Alain, by "upper" transverse bar, are you referring to the one closest to the bridge or the one beneath the fingerboard? Since you said you can see the squeeze-out, I'm assuming you mean the one closest to the bridge? Either way, if you haven't already done so, I'd recommend seeing if you could insert a thin spatula between the other brace and the top. Sometimes a separation can exist and not be visible.

Best,

Michael



Best,

Michael
Michael McBroom38982.4756481481

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Live to Play, Play to Live

Al, I guess the question is directed to me. I put a water sponge pack inside the guitar and inside the case and let it set for two weeks. The crack was still visible since it ran from the bridge to the tail down the plate joining line. The Soundboard had a natural coloration change down the join line and some of the appearance was in fact the separation of the finish itself. The crack went from larger than what we see on these photos to about a razor blade gap or less after rehydration but still to visible in my view. I went through the scrap stash, and found as close a grain match and color as possible, cut a thin tiangular shaped splint using a razor knife. I worked back and forth trimming ever so gently. I got the splint to a nice tight fit and then began working on the coloration issue using a couple of other splints I cut using a variety of products. Once I determined what worked then I applied it to the real splint, let it dry, and compared again. It took some time but I got a good match. I then applied a little Titebond to the splint and set it in the gap. Careful application to avoid glue smear. After drying I used a flat razor blade and trimed the top ot the splint to the existing surface. With a fine tip paint brush and MagnaLight to see, I dabbed a little more coloration mixture in the trim areas. After this was completed then I cleated the underside running along the repaired line using small spruce squares I also cut with some scrap.

Hope this answers the question and helps you Alain, the process was rather time consuming but the results were worth the effort.

Mike
White Oak, Texas

M. McBroom, I meant the brace just under the sound hole... It's a good idea to verify the other one as well. A bit of preventative medicine...

M. Spencer, thanks for the info. What did you use for coloring? Aniline dies?

I bought some today from Lee Valley. I want to try them out. In any case, I've got myself the makings of a pretty mean sunburst!

Thanks again!

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I'd like to be able to prove, just for once, that money wouldn't make me happy...

Alain,

I have several different shellac flakes, many with color. The coloration on this guitar was a vintage dark golden color, I mixed me up a batch of vintage dark golden color as best I could and then played with it from there. I have never used any of the dyes but that may work as well. Good luck with the repair and post some pics as you go or once finished.

Mike
White Oak, Texas