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After routing the top and back on #2, I noticed a pretty good hump at the neck block. It became very apparent after routing the top. I'm working on #1 but this repair is in the back of my mind. I didn't use a radius dish and just hand planes and I thought I had it good. I will buy a 40" radius dish for #3, I know that the best way to go but here I am with this problem.

I'm wishing I used HHG to attach the top to the body. That's another thing I plan on for all future guitars. I don't want to chance ruining the top as I put a lot of work into it. I'm thinking of using an oscillating multi tool to saw away the top of the neck block. Seems kind of dangerous but I'm out of ideas.

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Hutch

Get the heck off the couch and go build a guitar!!!!

Any chance of posting pics?

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Can you get past it by shaping the bottom of the fingerboard with wedges, shims, and/or sanding? I use HHG to attach my plates but I have never removed a top that I intended to reuse. The ones I have removed always get a little damage somewhere.

Ahhhh, very simple fix. Thank you.

I will post pictures when I get home.

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Hutch

Get the heck off the couch and go build a guitar!!!!

One of the advantages to fretting the instrument after the neck is installed with the fretboard on the neck is we can level and shape the fret plane independent of what's under it.

Also

I have a tutorial here on the OLF that countless people have used to eliminate the dreaded body hump which is what you have. It's called Flattening the upper bout if you want to do a search and see how that works. I still get PMs frequently from folks who tell me it works like a charm and it did on my Heshtones too.

Nothing wrong with Titebond original for attaching tops and backs and it's reversible, decent open time and again... if you are not perfectly set up for HHG use and respecting that short open time it will fail sure as shootin. HHG is marvelous but disrespect it's very narrow open time and it will bite ya. I know of a builder who gets $35K for their creations and they use almost exclusively Titebond Original.

So if you go the wedge route keep in mind that your neck angle in respect to the top and bridge needs to remain appropriate so you don't end up with a super tall or low saddle or bridge and have other issues that in the case of a very tall saddle will shorten the useful life of the instrument and encourage a bridge to lift.

Back to flattening the upper bout I believe at the time I wrote the toot that Martin did basically the same thing too to smooth out the transition of the fret board onto the body and not get any body hump. The technique also automatically creates about 0.010 - 0.015" of fall-away which is also very desirable.

Lastly early guitars are learning experiences and they need not be perfect but the real opportunity is what we learn for the next one so that these kinds of issues don't happen to us again. My first guitar was so bad looking.... that I put it out with my trash one Sunday night and I propped it up so people could see it with the hope that someone might come along, check it out, want it and take it. It played OK it was just not very visually appealing and it was a StewMac dread kit. I built it in a Residence Inn in Sunnyvale, CA where I was assigned to work for my day job.

The next morning when I went out to go to work someone had taken it out of my trash, checked it out, perhaps played and then threw it in my yard and left it.

Everyone is a critic

And really, really lastly although I encourage folks to learn repair work there is zero value in having to deal with a body hump. You will never deal with it again, it's not something that we have ever seen in the commercial world as something someone wants us to fix nor would we it's simply a slog and your best play is to get it over with and move on to the next one using what you learned here as the real value.

PS: My first had a body hump too.

Here you go Hutch: http://luthiersforum.com/forum/viewtopic.php?t=25931

This is not that hump. I used a flat UTB to avoid the normal hump but I somehow did not bring the neck block down where it should be. The hump is the width of the neck block. I can't wait to post a photo.

Now I'm thinking if I can release the glue just in that area to raise the top enough to get a sanding stick in, I can fix it right. There's no binding to worry about, only the center seam which shouldn't be a problem even if it come apart for a few inches.

_________________
Hutch

Get the heck off the couch and go build a guitar!!!!

Do you have a measurement of the excess neck block height?

Does the guitar already have finish on it?

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Steve Smith
"Music is what feelings sound like"

I haven't taken any measurements and there's no finish or bindings.

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Hutch

Get the heck off the couch and go build a guitar!!!!

I had a similar problem on one of my earlier guitars but the neck block was only up about 0.020”. I made a paddle sanding board about 16” long, then figured out the appropriate height at the bridge location to provide the proper fret board angle, made a spacer, taped it on and just sanded the 0.020” off of the neck block area of the upper bout. Obviously only a useful fix if the excess height is not too much.

_________________
Steve Smith
"Music is what feelings sound like"

_________________
Hutch

Get the heck off the couch and go build a guitar!!!!

I don’t flatten the UTB on mine and just sand the fingerboard tongue footprint flat with a flat sanding block. The top between the heel block and the UTB on mine is doubled with a top cutoff where the popsicle brace would have been in someone else’s construction so I don’t worry about making it too thin in that neighborhood. A combination of a bit of sanding and a veneer perimeter around the edge of your tongue might solve your problem without endangering your work. Trace your fingerboard tongue onto the body and mark the inside with pencil hatch marks. If you can sand until the hatchmarks disappear without getting the top thin enough that it worries you, you’re done.

Among the sayings that get repeated in my shop are “You can always make it worse,” and “Go over there and pick out another piece of wood.”

Hard to be sure from the photo but it doesn't look too bad. Like Bob said, a combo of sanding and a bit of veneer on the tongue might do the trick. Don't fret the board until after you install the neck so you can level the fret board on the guitar. Be careful so that the final fret board angle to the bridge ends up correct.

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Steve Smith
"Music is what feelings sound like"

Steve’s suggestion should set you right. You might want to put a mirror inside to see what the joints look like, hopefully that rather anomalous hump isn’t indicative of further internal problems…

Here’s a jig I learned in the Charles Fox course back in 2004. The pivot block is bridge height and located at the bridge position. The sanding board is 1/4” plexiglass and mimics the fretboard. I use it on every guitar as a final touchup for the upper bout.

If the angle of your upper bout is close this jig might solve your issue. If not you might have to sand more than comfortable as far as residual thickness of the top.

IMG_6872 by Terence Kennedy, on Flickr

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It's not what you don't know that hurts you, it's what you do know that's wrong.

What Terence shows is a much more elegant version of what I was describing.

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Steve Smith
"Music is what feelings sound like"

I just spent some time checking the angle and it looks real good. I'm thinking I can use Terrances jig and take a 32nd off the the top and the rest off of the finger board. Thanks for helping with this. Now I'm wishing I made a wider bench for working 2 guitars at once. That said, I'm going to put this aside until I complete #1.

_________________
Hutch

Get the heck off the couch and go build a guitar!!!!