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ok, i am in a bit of trouble now, i am having a multitude of problems with this top and finally something had to give I guess. after my warping problem (thanks alot for the help of getting that under control guys) and the discovery that if one wishes to thickness his top properly, one must have good tools and.....oh yes, and one must also actually sharpen his blades and listen to the literature he is reading , thankfully I did all the following before working on my beautiful walnut back. Now I know that the first guitar is really a learning experience but now I think I have gone and done it. last night after cutting out my top with a coping saw (i don't have a bandsaw or a woodworking shop around me that was willing to cut it out for me,even for cash....but im working on getting the bandsaw NOW ) part of the main seam broke free of the gluing so now I have a 2" long break in my main seam in my upper bout getting a little too close for comfort to my soundhole. I am seriously contemplating getting a new top, chalk this up to experience and hope my second go will produce better results. I figured I'd ask you guys what my best option was first before I go and sink another 40+ in another top. Thanks for the help I appreciate it.

Just reglue it. This area will be covered by the fretboard so it is not the critical part of the center joint. You should be fine.

What kind of glue did you use for the joint? Is your rosette already installed?

Up there I wouldnt worry to much either .... on mine I route a truss rod access slot there, so about 2 3/4 inches is going to disappear anyway .. then the FB gets glued over it.

_________________
Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

i've been using yellow wood glue and no my rosette isn't in yet, thats the next step and I didn't want to install it and find out that I really should have started again from scratch. i was just worrying that the crack could expand downwards and cause major problems down the road

C'mon guys! Part of a major glue joint fails for no apparent reason and you say, "Don't worry, it'll be fine, it's hidden anyways"??? With that sort of attitude, you could be building cars for a major US auto company!

No, it's NOT fine! The center seam often gives problems later on and if there's any question about its integrity, fix it before doing any more work. Split the seam, carefully joint it, and re-glue. Yes, it's a pain and yes since you've trimmed the board it'll be more difficult to clamp, and yes, it's necessary. Next one, check the joint before and after gluing, before going on.

The standards for guitar making are very high at this point and I, at least, am glad to have one area where people are demanding -- and appreciative of -- careful, skilled, quality construction.

Rick Davis is right. ... thats if the actual seam opened.

Examine it very close to see it it was in fact the seam or if the top split along an extreamly close grain line. If it was the seam ...follow Ricks advice but use NEW GLUE! ... and throw away your old stuff even if you purchased it last week. If you are using hide glue, mix up a new batch and pay close attention to the instructions on how to heat the stuff, its strength and how to use it....it has a very short "open time".

If it was a grain line opening up because of improper coping saw skills, just glue it and carry on.

And don't be so hard on yourself...after all ...its just a hobby....and suppose
to be enjoyable.




Blessings
the
Padma

_________________
.

Audiences and dispensations on Thursdays ~ by appointment only.


.

Also take a very close look at your joint.....
You don't want to see a V profile when looking at it on end....



Those are trouble -- as you can get them to candle OK, but when you lay them down flat, either the front side or back side is open while the other side looks really tight.

As you might imagine, these are quite weak and tend to split apart. The main culprit for me was not clamping cupped plates while truing up the joint. It can also happen when you joint plates separately. It can also happen if you don't clamp close to the glue joint when gluing (when plates are a little cupped or if too much pressure bowes them up)

If you have a joint like this, cut it back apart and re-joint.

Good luck

John

That's a little strong Rick. And I do not really agree with you.

Firstly, it didn't sound like there was no cause for the split. It sounded like it occurred during the use of a coping saw to cut the top out. Likely that the top was not adequately supported. Coping saws are very agressive and it would be easy to break thin wood if he was not careful.

Secondly, splitting the top apart and rejointing the top is a good idea if you have sufficient wood for the necessary trimming. But he has already cut out the top and cut the soundhole. So splitting the top at this point would be ill advised.

Barry,

You're right that I came on strongly. It was intended. And you're probably right that the joint opening was (at least partly) the result of sawing and stressing it (though it shouldn't have opened if it was well joined). But that doesn't convince me either that I was wrong about the importance of the center seam, even where it's hidden, or about the larger point about standards.

Your Facebook entry says, "Trying to build the perfect guitar." I'm good with that. I'm comfortable with cosmetic flaws in student guitars -- things like gaps between binding and body, imperfect inlays, and rough finishes. Learning to avoid those problems is part of the process. But structural elements like the soundboard center seam have to be right from the start, imho. Hence, I still say, re-do it, get it right, learn the lesson, and only then move on.

(By the way, neither of us mentioned the obvious: clean the split with De-Glue-Goo, work some fresh glue into it, clamp, flex it and, if it hangs together, call it good.)

Rick, I don't disagree with anything you said there. All is good.

Pretty simple since he said the rosette isn't in, that means likely the sound hole isn't cut either. Saw down the seam with a bandsaw, rejoint the edges and reglue.

I recently had a walnut back that was iffy on thickness near one edge, but I decided it would be fine. I glued the back and just for a little safety slapped the back braces on the next day. Well guess what? I didn't take time to install the back graft at the same time. That thinner iffy area was stressed just enough to pop open the seam, right up to the first bottom back brace.

I'll be doing the same as I recommend, chisel off the back braces, saw out the seam line, rejoint and reglue. You can bet I'll slap on the back graft this time. In thirty backs glued up this is the first and only seam that ever popped for me. First time for everything.

I'd be for fixing the joint before proceeding, it'll be a tiny investment compared to building the whole guitar. and..... good luck!

_________________
http://www.dickeyguitars.com

Bruce, Look at his first post. He has no bandsaw. Just a coping saw.

I have learned that online advice is most helpful if you tailor it to the person's level of skill and available tooling. That was my concern with Rick's post as it appeared to ignore the fact that he as no bandsaw, and the possibility that the soundhole was already cut out. I would agree that the presence of a soundhole issue is not clear, but in that case, I would ask the poster a question instead of firing off a recommendation based on an assumption, which might ultimately be proven to be wrong.

To be honest, I am also a little bothered (I thought it would go away if I slept on it, but it didn't) that Rick first off, felt the need to chastise me and Tony for giving the advice. And then he looks my profile up on Facebook and uses a quote from it to sort of imply that my standards are not up to it.

Rick, the fact of the cracked top are not clear. My recommendation may be valid if the soundhole is present and he has no bandsaw available. On the other hand, your recommendation may be valid if those two issues are the opposite. We don't know and probably never will. That is the nature of internet forums. You have to make some assumptions and try to help where you can. But it is not good etiquette to blast or denigrate the integrity of other luthiers, no matter who you are.

Barry,

My only intent was to make the point that the problem was not trivial. I am sorry if you felt I "blasted" you or in any way impugned your standards. I complimented you on your goal of making a perfect guitar and said nothing whatsoever about your own standard of work. Facebook pages and websites are documents where we present ourselves to the public; you're welcome to look at mine and comment if you like, publicly or privately. My point was not that you were being hypocritical but that your response to the problem was, IN MY OPINION, overly cavalier. And then I thought you and I actually worked it out and agreed -- do a good job of regluing, test both the repair and the rest of the joint, and act accordingly. It's probably not the course I would take with one of my soundboards but it makes sense under the circumstances.

There has to be room for disagreement without giving or taking offense. I did not cross that line. We agreed about one possible solution to the problem, we were both respectful of everyone who commented, and that's all good.

wow, i didn't think my top would bring on such heated debate. I have been reading along for the past few days and basicly come to this conclusion. Thanks to my extremely generous parents, they have helped me and chipped in to get me a small 9" bandsaw I can use in my room (probably because I complained about my problem so much haha) SO i think i am going to TRY and split it, re-joint it and glue it back together.....if that fails my girlfriend is allowing me to run back to the woodstore and get another top. The only concern is glue clean-up since I am at my finish thickness already (3mm) but we will see what happens. Thanks for all the suggestions, especially those from Barry and Rick. The only thing that kinda swayed me to cutting and re-jointing is what truckjohn mentioned about the v-groove when jointing (it was my first joint ever with a planner with a dull blade no less...i was impatient to start what can I say, i've learned my lesson haha) and im almost positive that I did that because I have fond memories of candling the wood and it looking better on one side then the other (larger gap) the sound hole isn't cut out yet to im gonna split it and do it right, i'll tell you guys how it went, thanks for all the help, this newbe appreciates it