CORRECTING A BAD NECK RESET MARTIN D-12-35

[Greg Harmon]

This may be a problem that you've all ran across in the past but it's the first time I've had to deal with it. A person brought a nice D-12-35 (early 60's) in the shop with a pulled neck. When I removed the neck I found that it had been reset in the past and the person has overcut the angle and has corrected it by cutting back about a 1\16th" on the top under the fingerboard. I believe that I can get a good angle and fit without losing much or any more ground from the topside of the neck joint. My question is should I go ahead and reset the neck like this and try to deal with the 1/16th inch scale problem by compensating the saddle or should I build the neck heel back to where it should be and deal with the cosmetic problem of hiding and finishing the new wood where the neck joins the body. This is my first attempt at posting a question and I hope you good folks can understand what I'm describing. I've gained a lot from you're discussions over the years. Thanks.

[Rick Hoey]

I would fill the existing slot and recut the slot at the proper distance after the neck is reset. If you do a good job of filling the slot, and darkening the ebony if necessary, the fix could be close to invisible if the distance is only 1/16.

[Jeffrey L. Suits]

I agree with Rick, reslot the saddle if necessary--I'd check the scale, before I filled and re-routed.

Or, for that matter, if the customer should decide to go for a fully compensated saddle...

[Jim Bancroft]

If the scale length can be corrected at the saddle then that is the way to go, if not then I would add some mahogany shims to the heel to lengthen the neck.

Jim

[Alys and Simcha]

Hi Greg.... If you mean that someone has cut too much off the heel where it fits against the body, I'd try to pack out the dovetail and body-to-neck fitting surfaces with temporary matchsticks or whatever, until the neck is held firmly at the correct angle AND the correct distance from the bridge. Then I'd use the end of a steel rule as a spacer and neatly scribe down the sides of the heel, parallel to the guitar sides. Then take out the neck, trim the heel back to the scribed lines and glue on two shims of light colored rosewood or walnut made the same thickness as the ruler. ( you'll need to make some little angled blocks wrapped in paper so you can clamp the shims in place while the glue dries. )
If the previous neck reset was inexperienced, you'll probably also need to shim the dovetail joint and recarve it to a good fit. For the dovetail shims, I'd use something like poplar or birch.

When the neck is finally reset, you'll have a narrow strip of slightly darker wood running along each side of the joint between heel and guitar sides. Not to difficult to retouch with lacquer and a bit of colour. They won't be invisible, but they won't look offensive, either.

The trick in this repair is to temporarily jig the neck into the right place and angle, and then scribe the heel parallel to the guitar sides.

[Ronnie Nichols]

Concerning the scale being short, this may be one of those Martins that had the bridge installed in the wrong place at the factory. I've run into more than one Martin from this general era that had the bridge installed incorrectly at the factory. I've been told that they tried to install the bridge to the body prior to attaching the neck during some period of time. Evidently it didn't always work out like it was supposed to. Shimming the neck slightly at the dovetail joint should help with this problem. I agree that a small strip of wood at the neck to body would not be too offensive looking. I'd probably try to use mahogany to match the neck wood as close as possible.
Ronnie Nichols

[Greg Harmon]

Thanks everyone for all the good tips. I decided to go ahead and reset the neck in the usual fashion and deal with the notation problems if any arise when I get ready for the set up. I got a good fit and tight shims when I set the neck in. I haven't put the fret board over the body back on yet and I can't hardly keep from setting a couple of dowels to lock it since it is a 12 string but I probably won't. I hate doing things that might throw another luthier a curve if the neck ever has to come out again. Thanks again, Greg Harmon.