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I am(was) almost finished with my first build. OM size, just glued on my bridge and drilled the holes for the strings only to find out that my bridge plate was too far forward. Somehow in the transfer from plan to wood I either changed scale or put the plate in the wrong spot. Just a 1/4" too far forward.

So I spent a day removing the plate, and in so doing did some pretty good damage. I left a sponge overnight on the plate and when I began this morning there was already some swelling of the top at the bridge on the bass side. As I proceeded with my spatulas, the top in front of the bridge began to sink and split. I think I was using too much pressure. I ended up finding a piece of aluminum and putting it on the stove to use as a heating iron. This worked eventually, should have started this way.

What do you guys think I should do here? I cut a larger bridge plate in both dimensions to patch the underside and give the soundboard support over this broken area. It's now going to be bigger than it should be but I need to support this area. The fibers on the top swolled up and so they won't lie down perfectly flat now. Should I glue on the bridge plate first and try to clamp down this broken part with a caul to make sure it lays well on the plate? Then the bridge?

Any things I should consider here? It's never going to be invisible but I just don't want it to explode when I string it up. I've only got a few days before I have to pack up all the tools and head for med school so I want to get this at least to a point where I only have to redo the french polish.

Sorry for that. It's a bummer for sure. I made a stick that stretches from the nut to the saddle. No mistakes with that. Your smart you'll figure it out good luck with it.


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Well I certainly feel for you. I know you worked hard on it and it certainly is disappointing. But honestly, from the photos, it looks to me to be structurally compromised. Set it aside, go to med school (which I am sure will take your mind off it), and pick it back up next break - replacing the top. I think it is the only solution that will last.


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Man that's brutal. If it were mine it would be getting a new top.

Sigh, bummer. Re-top. repairing this on a 100 year old guitar would be one thing, but not one that is just starting out. Google John Greven's method for re-topping without losing the bindings and purflings. That will be a lesson!!

_________________
Jim Kirby
kirby@udel.edu

Another vote for a new top - pain in the butt but you'll be glad you did. I'm just finishing up one that I braced too lightly so it's getting a new top that is hopefully braced better.

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Steve Smith
"Music is what feelings sound like"

Add my vote for a new top. That's too bad, but these things happen. When you're done it will likely be even more lovely.

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George :-)

No advice for you, but you sure have my sympathy. So close to the finish line too.

I don't think you can salvage that top either. And you will be far happier with yourself in the long run if you put a new top on so that it looks good.

This reminds me of one of my first builds. It was #2 and I was trying out my new pedestal buffer. I was still trying to figure out the best way to hold the guitar while buffing while also learning good buffing technique. At this point I didn't have either and the buffer caught the corner of the guitar the guitar slammed into the floor. It bounced several times before coming to rest a few feet away. The floor in my old shop was wood and the damage was relatively minor compared to what it could have been, a few cracks in the back. I know that disappointing feeling of being so close to having a guitar finished only to have something major go wrong.

And then there was the time I glued a bridge on locating it off the 11th fret instead of the 12th. New top for that one...which failed within a year (my first experience with curly redwood). 3rd top worked good

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Josh House

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And then there was the time I glued a bridge on locating it off the 11th fret instead of the 12th..

Yeah, getting one of those back in the mail next week. What I want to know is, how the haymaker did I miss that in setup? Sheesh...

I did only one 'launch' at Larrivee. The floors were all concrete (and you couldn't convince Jean otherwise), and one second I'm concentrating with extreme intensity on one wee little swirl near the binding, and the next the guitar is ripped out of my hands like someone hit it with a baseball bat and I'm standing in a pile of splinters getting the evil eye from the entire shop floor. Once was enough....

First off, I would tend to agree with replacing the top, however it could be fixed but you will always see the crack and wish you had replaced it.

Second, no one addressed why this actually happened so let me explain how to successfully remove a bridge.

#1. Never use water to remove anything from a guitar. That is the sure fire way to discolor wood and make it swell up and get soft, which will allow the fibers of the wood to tear (as you found out).

Always remove any part with heat. Heat will soften the glue up so you can slide a separation knife between the parts. A simple tool you can make is to get a good quality 1" putty knife and grind the thickness down for the last 1" or so making the end of the blade fairly thin. Then round off the corners to about 1/4" radius so there are no sharp edges. Now you want to put a slight bevel on the underside of the leading edge. You want the bevel on the under side so you do not gouge into the top as you push the blade between the top and the bridge (if anything it will gouge up the bridge). You can also put a bend in the blade near the handle so when laid flat on the guitar the handle will be above the soundboard. Now you have a great tool for removing bridges or any other part you need to separate. Just be sure you don't have any sharp edges to dig into the top.

Below are pictures of my separation knife I made along with my ceramic blanket to protect the top from the heat. The blanket is ceramic and will shield temps up to 2500 degrees. I place it over the bridge and then place a regular cloths iron on the bridge for a few minutes to soften up the glue. The material is about 1/4" think and can be bought at a fireplace supply outlet. However, you can make a simple one out of 2 or 3 thickness of regular corrugated cardboard and then cover it with either tin foil or that aluminum heating duct tape (not the regular duck tape but shiny aluminum).

That is how you should have removed the bridge and you would have probably avoided ripping out chunks of your soundboard.

Hope this helps and maybe you can avoid a problem like this in the future.

Sorry to see that nice guitar top ripped up but at the very least you can say you learned what not to do...

Bob

I'll go against the grain here (ha ha) and say you should repair it. It will certainly show, your repair may fail, and you will never be able to sell this guitar... but if you think things through, do your best, and pay attention and learn from what happens then you will absolutely be better for it.

I actually did the damage removing the bridge plate. Getting the bridge off was a piece of cake, using a ground down putty knife as mentioned.

I glued on a bridge patch tonight that covers the whole torn up area. I figure if I'm going to replace it then I might as well just glue a new plate and put the bridge on and see what happens and then later on do a whole new top.

Thanks for the commiseration, interestingly I feel more like there's a new challenge than like counting it as a loss. Round two!


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soma_hero, Ahh, Sorry I missed the part where you said you were removing the plate. I know a lot of guys use damp rags to soak a bridge plate off and I did my first one that way but I also split the top it too, so from then on I have always used heat. I place a dry towel on the top (after the bridge has been removed) and put my iron on that. I use a regular cloths iron set to medium and let it get good and warm but keep checking the top to be sure I am not marking up the finish.

Yea, you can repair the damage but you will probably always see it. Hopefully it is a clean split and you will be able to clamp it together to get it to fit smoothly. If you are lucky it will fit back together perfectly and the crack won't be quite as noticeable.

Good luck on the repair and post some shots of it when you get it finished.

Bob

So often "better" is the enemy of "good enough". If you had glued a second plate behind the first then you could have avoided some heart ache. At one time that was a recommended patch for that problem, but in our quest for perfection people no longer recommend that.
From the pictures, it looks like the spatula followed the runout in the top. It doesn't look like that was such a great top, so when you do get around to replacing it try to pick one with a bit less runout.
If you find the guitar sounds great after you have it together and you don't want to re top it , then with a little bit of bondo and some gloss black lacquer you could cure the cosmetic deficiencies (mask off that lovely rosette first) .

I'd say it depends on what the rest of the instrument looks like and how you feel about the rest of it. If you like the rest of it, you might want to just glue the mess up and put a new plate in, just to see how it sounds. You can always retop it later. If you plan on building more instruments and feel you can do better next time, use it as a beater.

I think I agree with Haans on this one. I tend to look at first guitars as an exercise in "getting it done". I had so many snafus on mine (and my second and third... that if I'd engaged in major "redos" each time I fear I'd have gotten so frustrated that I may not have ever gotten there.

I think I'd recommend doing some research on the best and most cosmetically invisible repair that you can, and chalk it up to experience. the choice of glue is one variable that will make a big difference. CA (crazy glue), while appropriate for repairs on dark woods, would stick out on the spruce like a sore thumb.

Removing a top in the manner described is a complicated exercise in and of itself, and seeing as how this is your first guitar, I'd say there's risk in causing other cosmetic damage that might require other repairs.......

Good luck!

Really! The intonation of the 12th fret harmonics and fretted notes must have sounded at least a little strange

Now, the simple perfect rectangularity of classical bridges can lead to some dicey moments - oh was I praising fish glue for it's long open time on that one. I don't think I would have been able to get it to work with the saddle behind the tie block

_________________
Jim Kirby
kirby@udel.edu