Advice for non-luthier, repairing a crack in a maple electric guitar neck

[John Engström]

Hi,

I work as a software maker, but I love stringed instruments and the art of making them.

My first electric guitar is a japanese Daion The Savage, made in 1983.

It's not an expensive guitar, but I love it very much.

I have decided to see if I can restore it myself, since the best luthiers here are out of my price range for this type of job. I do go to them for affordable jobs like setup and fret polishing. The ones I can afford have scary reputations. I want this done as well as possible.

The neck is maple, has a rosewood fretboard, black binding and clear nitro-cellulose lacquer finish.

The original neck has a 20 mm deep crack across the headstock glue joint, through the lacquer.

The spare neck I have been able to find has a 50 mm deep crack at the bolt-on neck joint, and is from 1982. The wood is somewhat better on the original.

I want to repair both necks, and choose the best one to put back on the guitar.

My first call for advice goes: Is there any chance the bolt-on joint crack is less detrimental to the instrument, than the headstock damage, if both are properly repaired?

I'm leaning towards a no. I guess the original neck, with repaired headstock, is probably be the best choice.

I guess both cracks can be repaired by the following steps:

1. Clean up the surfaces in the crack as much as possible without reshaping them.

2. Apply hide-glue or epoxy-glue (following the corresponding optimal procedure)

3. Clamp well, let it set and cure fully

Second question: Is hide glue the best choice for repairing maple in this situation? What I have read seems to indicate so. I can get West System 105/205 epoxy.

For the bolt-on joint, the repair would be hidden, but in case of the headstock, the lacquer would still be cracked and the glue might show. It seems I would have to refinish the neck.

That brings me to my third and last question: Is it possible to sand off or otherwise remove only part of a clear nitro-cellulose coat, and refinish only those parts? If not, I guess the entire neck must be stripped and refinished.

Thanks in advance for any advice!

I can get photos if that helps.

(PS. I love the information on frets.com, and I'm eating it up. Thanks so much.)

[Paul Verticchio]

Hi John & welcome.  You came to the right place.

Could you post pictures of the damaged necks?  Close-ups & long shots would be fantastic.

Have a great one,

Paul (:

[Pierre-Antoine Roiron]

Yes, we need photos to give an advice.

There's a question I can already answer : you can sand a little nitro finished area of a neck and apply a new nitro coating. Are you really sure the finish is nitro, seems odd to me for a Japanese 80's made?

[Chris Rochow]

To know if it's nitro John,  in a very "not seen" area....take a cotton swab with some acetone on it.  Then apply a 'spot' area with the acetone... if it melts that area...it's nitro.  Poly will not be affected by the acetone. :)

[John Engström]

Thanks so much for the knowledge!

I did this test and came out with a clear and non-melted result: Polyurethane.

[John Engström]

Thanks for the helpful replies!

By the test Chris suggested, I have determined that the lacquer coat is most likely polyurethane.

At the crack in the neck joint, the lacquer looks about a half millimeter thick.

The cracks are a bit deeper than my original description after close re-examination.

Here are first three photos, of the damages to the original neck headstock, glue joint.

Unfortunately the camera is terrible (built into business phone), however the images seem to be of some use.

[John Engström]

Here are photos of the damage to the spare neck at the bolt-on joint.

Since these have turned out to be poly finishes, I can rephrase my last question:

Is it possible to sand off or otherwise remove only part of a clear polyurethane coat, and refinish only those parts?

Searching the internet for information, it seems partial refinish of polyurethane coat is something doable but rarely taken on, since it is hard to get right.

[John Engström]

Here are full shots of the necks.

[Paul Verticchio]

Great photos John.

The following is 'my opinion' based on the supplied photos.

The original neck: The break/crack seems to be right on the scarf joint.  I would simply clean the exposed wood with Naptha, rough-up the surfaces w/220 paper, glue (with white glue) & clamp. The white glue squeeze-out can be cleaned with a cloth dampened with very warm water & no touch-up should be required.

The spare neck: same thing.

I would not use splines or support dowels in both repair scenarios.

If a neck is going to crack, yours have cracked in the best ways possible to affect invisible & appropriate repairs.

There's a tendency to over-think these simple repairs.  Keep it simple, proceed slowly and you'll have both necks 'service ready' in no time.

Best of luck(-:

[Mark Pollock]

Paul is steering you right. I'll just throw in a couple thoughts here -

Remember to try a couple of dry test runs with whatever you are going to do before you actually add glue.

Otherwise, yes, glue, and don't forget to use some wax paper to keep things from sticking. From Frank's excellent Frets.com site -

http://www.frets.com/FretsPages/Luthier/Technique/Structural/Broken...

On the spare neck, I really don't like the look of that split. It will get wedged open every time the neck is bolted on. You would probably need to drill it out and put in something else - a threaded steel insert might be best. Or a phenolic rod.

[John Engström]

Wow, that looks like very similar damage indeed, thanks for the link!

Though that looks like a easier finish to repair, it is a good example of finish repair in a similar situation.

Sorry to hear your verdict on the spare neck damage.

Another positive thing about the spare neck I forgot to mention is it has no fret wear, while the frets on the original are considerably worn (nickel-silver). I guess they are good enough if leveled and polished by a good Luthier though, but that would have been a nice thing to postpone.

Since the full strip and headstock repair job will take so much time, I think I'll still attempt the spare neck repair first. I think I'll take your advice and use a threaded steel insert. Thanks so much.

[John Engström]

Sounds like good news to me. Thanks a lot for your opinion. Your post helps reassure me to plan this operation.

I don't know how to separate the headstock, to expose that entire scarf joint area, without breaking the headstock binding and possibly more. Therefore I'm not sure how to rough up the surfaces inside such a tight crack. I guess I could try and sand as deep as possible by tugging on the sandpaper. Is there some super thin sanding device for this purpose?

Since the finish is poly, I guess I'm refinishing the entire original neck, I can perform the headstock repair, as you described, when it's stripped to make that part easier.

I'm somewhat surprised you suggest white glue, but I understand how it would probably work in these cases, and I fully trust your advice. I have noted some pitfalls for white glue while studying this; (1) possible warping and weakening if glue joint thickness is uneven, (2) tendency to fail under dynamic stress and (3) it can expand while curing so must be very carefully clamped. These factors don't seem to be a problem in either case here though.

Do you think hide glue and (suitable) epoxy are more difficult to use than white glue for an inexperienced woodworker like me?

I have been playing this guitar with damage for 15 years, but it has never been properly cared for, since it was not in the best condition when I got it, and then nearly destroyed by a misinformed teenager (also me) in worse ways than the headstock thing. Time has made this headstock damage look huge and glaring in my eyes. :)

Based on your opinion that both breaks/cracks are favorable, I'm considering repairing the spare neck first, and switching to that, to get the shiny headstock joint back right away.

After further repairing the headstock damage as you describe, refinishing the neck becomes less urgent and can be done with the greatest care.

PS. I am inspired and have sanded the body, which is now ready for refinish and new electronics.

The body wood has three pieces and no grain matching so the refinish will be opaque, like the original.

The original cream white is no more, it wants a premium orange guitar finish. ;)

[John Engström]

When I wrote "without breaking the headstock binding" I should have said veneer.

Learning..