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So I was cutting out my WRC top when the scrap portion fell off. I thought, at first, it was a bad centre join but no, it's a crack in the top. I couldn't see it until I flexed it slightly. So then I flexed and looked closely to see if both halves were cracked in the same place. They aren't, but the other side has a similar crack in a different place. As both cracks are invisible until I flex them, I thought the solution might be to wick CA from the back. As you can see the CA wicked right through and spread a little on the front and didn't seem to glue the crack together. I've now wicked some more CA and left it to cure.

Should I just scrap it? It was a $30 top and what's more that was the only curly sapele rosette blank I had and I'm a long way away from the suppliers! Grrr...

Click on the photo to see it better.

You have to post the photo for us to be able to click in it

Yup, sorry, I had to reduce the size of the photo. You were very quick off the mark Michael.

CA Wrong adhesive to use You will have sone discoloration that can not be removed. Now if this is personal guitar there will be nothing wrong in the strength or sonic attributes of the top. if for a client, start over.

I would've probably used some titebond..

Any PVA or HHG would have been fine but CA will leach in to the cellular structure of the wood and darken it. Now from what I see this is not a biggie as many pieces of Cedar will Have dark discolored areas in the wood. So it is going to look very natural but if for a client I would start over because the dark spots are a misstep by the builder.

I agree with Michael. If there wer other dark lines on that WRC top than I'd have no problem using it, but it sure looks uniform in color and those two dark lines will certainly show up more.

If you'r going to scrap it, to save the rosette, you can run it through the thickness sander till you have only a thin layer of cedar holding the rosette in place. Using a good sharp exacto knife, cut out the rosette, from the back side. Hold the knife so that it is angled inward (toward the sound hole) and then work on removing the inside and outside cedar from the remainder. It might be tedious but you can do it. Cut close to the mark, then sand the remainder away.

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I have to admit, Michael, that when I applied the first drop of CA and saw it spread, I started mentally kicking myself.

I don't have 'clients' so that's not a problem. On the other hand I am a bit of a perfectionist but that's my problem. I think I'll apply a little shellac to that area. That should show me how it will look finished.

If I decide to carry on with it, might it be an idea to reinforce these two areas with small 'centre-joint' triangles or even a miniature 'back-graft'?

Edit;
Thanks Rod. I've already been thinking about how I could salvage the rosette. I think patience is the keyword here.

I don't think they would spread anymore but if it would make you feel better, it won't hurt anything to add a small triangle graft on the inside. The edge will be held in place of course by the lining and or tail block which ever it comes into contact with.

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"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson

I doubt you will need any as the repair will be stonger than the surounding wood. If me I would use it for a personal guitar. the flaw is really pretty minor and sonicly it is no issue and structurally you solved the issue.

I'm sorry Dave my friend that this happened to ya

I would be pretty paranoid about about this top set now and wondering what may be awaiting me that I don't yet see. Two cracks in a top set is not a confidence builder. OTOH better now than after you braced it and attached it to a rim and went through the finishing process......

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Ann Arbor Guitars

Just what I was thinking Hesh (I think we must both be a bit 'obsessive/compulsive'). Thanks for the sympathy too. That also helps.

What would be the harm in cutting the top into three pieces at the cracks and then regluing them together. That way the kerf of the saw would eliminate the darkened area and stress relieve the area near the crack. Since you have not cut the other side of the plate you may not lose too much width. I trust that the right crack does not go through the rosette...... it looks like the grainline just kisses the left side of the rosette.

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Steve Walden
Aspiring Builder,
Bartlesville, OK

Dave, I would try to save the rosette and start over with a new top.
WRC is notoriously brittle and you may have stress lines where the cracks appeared, new cracks could appear along the same lines higher on the top.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

If your going to use the top, and have a 'v' gouge, then cut a 'v' grove along the crack, and cut a 'v' in matching scrap, and you will have a perfect super strong fit, then do the other side.

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Sorry for the high-jack Dave my friend I'll go back into stifle mode.

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Ann Arbor Guitars

Anyone ever seen a sunburst cedar top?

Steve

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Or you can try flooding the whole thing with CA. It will come out even and you'll get whatever impending cracks that are just waiting to declare themselves...

It might look funky, but you might be able to claim that it's an exhibiton grade set!

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

$30 a top?
I would scrap it and not waste my time.
Can be used for centre grafts, soundhole doughnuts and the like, and kindling.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

You said it yourself, like Laurent said it's a $30 top, remove the rosette and reuse it and the rest of the top becomes wood for grafts, soundhole patch and practice wood for setting up your rosette cutter. If you were really happy to carry on using it, you probably wouldn't have posted the thread. Start on another one, you know you'll never be really happy with this top.

Colin

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Nearly a year ago I had to fill a crack in a similar spot on a WRC soundboard. In my case I caused the crack by dropping something which clipped one end of the top so I wasn't concerned about the structural integrity of it moving forward with the guitar. I went with CA glue like yourself, expecting it to be visible on the finished guitar. I found, unlike with past experimentation with CA and spruce tops, that it left no visible traces once finished. I should say that judging from your photo, my WRC was much darker than yours, with a pinkish hue, which might have helped make it invisible.

I'd also add that in my case it was a $120 top... if I were dealing with a $30 top I'd be tempted to toss it and start from scratch, especially this early in the game.

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Richard
http://www.guitarmaker.com

A $120 WRC top??? I dont think I've ever seen that.

Thanks for all the replies and suggestions. I went back to it the next morning and the CA had hardened and the cracks solidified. I took a scraper to it and removing only a few thou of wood the CA on the surface dissappeared and the cracks are virtually invisible. I think I'll finish cutting out the profile, flex it some more, and if no more cracks show up, I'll carry on with it.

$30 is not a lot to some, it's more to others (especially to some others living on a pension) and ordering from the US, with shipping, etc., it can become a $60 top quite easily.

I'm a bit late with this post, but there's been a storm in S W France with gales up to 110 mph. We were without power from 4 am yesterday morning to 7.30 pm. and the internet didn't come back until this afternoon. We were relatively lucky, we only lost our apple tree. A quarter of the pine forest has been flattened, a lot of trees fell on houses. 180,000 homes in the Gironde are still without power and a lot without water and some will remain so for several days. Amazingly there have only been 2 or 3 fatalities.