Repair on neck of Martin 000-15 ... take 2

[Brad Elbein]

Well, eschewing all of the expert and good advice, my young friend and I removed the neck of that guitar.  We heated the fretboard attached to the soundboard until the glue melted, then worked the neck back and forth until the dovetail (it isn't exactly a dovetail, actually) worked its way out.  The glue looked pretty awful--in fact, it looked rubbery more like someone had used a glue gun than either carpenter's glue or hide glue. 

 

So, now we have to fix it.  I'm going to post a picture to see what advice I can get. 

The point of this illustration is that when the joint between the neck and the body is snug, the fretboard is 1/16 (the height of that coffee stirrer) off the soundboard.  When the fretboard is snug on the soundboard, that old crack in the neck/body joint opens up. (Yes, I regret to say I'm responsible for those scratches in the soundboard.  Damn.  More refinishing experience coming my way.)   

I'm assuming that the first thing we do is (after we clean up the joint) is to re-bolt it, string it, and check out the action.  I have to assume it will be bad.  What do I try next?  I could put a shim under the fretboard ... or shim the neck joint to put it at the proper angle to the soundboard? I did buy the book suggested elsewhere, but it hasn't arrived ... so ... All ideas appreciated.

(Except taking it to a real luthier.  That's not in the cards.  This is as close to living life on the edge as this kid or I are ever likely to get.  As sad [or as much of a blessing] as that is.) 

[Mark Pollock]

What I do is take a flush-cut saw and make a cut where the tenon meets the fretboard - this makes some space so that the fretboard can bend to match the top. The fret extension is just not that big a deal for most players - most of use just don't play past that 14th fret enough for it to matter.

What is far more important here is that you get the neck and the fingerboard that is NOT the extension oriented properly to the guitar. You can just bolt it on and see how it looks - how many bolts are there anyways? (I'm dealing with a mid-70's Epiphone that was a bolt on with four dowels. That single bolt is not enough to hold the neck on, so I need to work on another bolt. In my case, there is a strap-peg on the heel, so I can just run a bigger screw through there to accomplish my job.)

Scratches are a pain. Get some metal shim stock so that you can tape it to the surface of the guitar, and you can prevent a lot of these problems. (If you get 3/1000 thickness stock, it also makes a KILLER scraper.)

[Brad Elbein]

One bolt.  Would seem that two bolts would make more sense, but I guess Martin wanted to save that $0.59.

[Mark Pollock]

Money saved - $0.59.

Damage to carefully honed 175+ year reputation - priceless.

[nathan clark]

"when the joint between the neck and the body is snug, the fretboard is 1/16 (the height of that coffee stirrer) off the soundboard"

That is normal. So long as the bottom of the fretboard at the neck body joint (on either side of the tenon) contacts the top the remaining fretboard tongue will easily clamp down to the top. You will need to make/buy the appropriate clamping caul and c-clamp for the fretboard tongue when gluing the neck back in place. Check out photo 18 (this is my article that I refenced in your previous post):

http://fingerlakesguitarrepair.com/martin-mortise-and-tenon-neck-re...

[Ned Knepp]

I agree with Nathan, the fingerboard extension is a bit warped because of the loose heel. It should glue back into place easy enough. I don't think you really need to restring the guitar to check the angle. You should be able to get a good idea with a straight edge. It needs to be long enough to reach from the nut to the bridge so you can see how things align. Pictures of this would help us know what is going on. .