Split Headstock

[Rob Gray]

First Post! Thanks for providing a great place for learning and sharing repair and restoration techniques.

So I have a headstock that split clean through due to what i suspect is a lack of PVA adhesion to the rosewood lamination. I plan on pulling some p220 through the split to clean out the old glue. I will then re-glue it with hot hide glue.

Now the big question I have is, would there be any other option for finish touch up besides just straight up respraying the whole headstock? I've been searching the forum about Cellosolve Butyl, but, many threads suggest it is not worth the health risks? Will Toluene or Acetone work?

I have attached a photo. My primary concern is getting the color coat to melt back as the crack is very small and there is no missing chips of finish. Perhaps I could use the airbrush to spray one coat of color, spray something to amalgamate the finish, then a couple coats of clear?

Thanks,

Rob

[Paul Verticchio]

Hi Rob & welcome to the forum.

The first thing you need to determine is the type of finish: poly or nitro lacquer.

If it's nitro lac, you'll have a good chance of blending in the repair. If it's poly, you'll just have to work at it harder. I believe the general consensus of the forum is that poly is the most difficult type of finish on which to effect 'invisible' repairs.

Also, it's impossible to get poly to re-flow like lac, so finish amalgamation is out of the question if it's poly.

Once you tell us what type of finish you're working with, answers will likely pour in.

Again, welcome to the forum and best of luck :)

[Thomas James]

Rob, did you build this? http://www.ripcustomguitars.com/   I would re-glue with epoxy and refinish the headstock.

[Rob Gray]

It is Mohawk Nitro and Colortone lacquer pigment. Sorry I left that out, I glossed over that detail as I made this one.

I did indeed build this one about 7 years ago and I was getting around to finally painting it. It's one of my personal guitars. The headstock took a blow on the shelf above my bench and split. I'm glad i did it before it had strings on it, I surmise string tension would have caused more problems. I'm pretty rough on my personal guitars.

Thanks,

Rob

[Thomas James]

Looks good. I trust you'll get it good as new.

[Kerry Krishna]

Rob, I am not understanding this odd damage at all, and your explanation

 is confusing me too. Were would this rosewood lamination you are talking about be?

 Can you post a pick of the back of the headstock for clarification?

[Rob Gray]

It is a three piece neck. Maple with rosewood veneers in between, i.e. Maple/rosewood/maple/rosewood/maple.There was a delamination issue between the the maple and rosewood or I simply didn't get enough glue in that area. Pictures worth a thousand words right?

One suggested epoxy. I personally feel that HHG would be best and have the simplest clean up and paint touch up. That being said, I'm definitely open to being persuaded other wise if the reasons are compelling.

Thanks for checking it out and offering some additional insight.

[Thomas James]

Much better view. My thought process: HHG glue requires a tight fit of the parts. You may not of had that originally? If you sand this 'crack' you may create more gaps. Rosewood has oil/resin in it, so it should be freshly sanded and perhaps cleaned with a solvent as well. Epoxy is good at filling gaps and for gluing tropical woods. You may have more to clean up, but maybe a better joint? The headstock face It is a small confined area to refinish. Cheers.

[Kerry Krishna]

 Thanks for the photo. Can I ask, are you still constructing your necks this way?  If so, after seeing only this one guitar, I would be doing a veneer on both the front and back of the headstock as this seems vera weak style of join, especially considering the  style of headstock, and the constant force that will be being applied by the radical string angle coming off the nut.

Actually, I would  be making them quite a bit thicker that veneers, and I would  defiantly be running the grain of the 'veneer' on a horizontal plane to this headstock. 

 I know, you didn't ask.... This sort of thread really helps to build the Forum's knowledge base though!

I am so glad you started it... 

[Russell Vance]

Hi Kerry,

This headstock form has been around for quite a while (read birth of "Metal") and while it's not everybodies cup of tea, it's a valid style statement.  Most of these are maple and have no veneer or headstock facing and a lot are also one piece flat sawn headstocks with a scarf joint in the neck to facilitate ease of manufacture and strength across the peghead face.  The joints in the harder , fine grain  maples are hard to do well and when they separate, glue starvation and or poor gluing technique is often evident (which is common to maple anyway). Also not unusual for the top corners (where there is a little piece of maple glued on the original neck billet and the E tuner hole) to literally fall off when clipped.

These maple scarf joints give way occasionally and the segmented/laminated  headstocks like this also separate when given a knock or a drop (lots of leverage, angles and sharp points to wreck joint integrity).

The string angle is a bit disconcerting to look at but doesn't really do much because the strings are locked at the nut and the leverage is not over the full string length (as in a floating string and nut arrangement) - actually less tension than a normal neck and not subject to as much whiplash when hammered.

The use of rosewood stringers in a maple sandwich and the very skinny headstock is the cause of this weakness, and my solution would be to stick it all back together, glue on a new cross grain oriented  headstock facing plate, refinish the facing plate and get on with it. 

Note, the use of dissimilar wood (with regards to hardness, density, expansion and contraction and gluing suitability and compatability) make a neck weaker, not stronger - stringers are, in my mind, best left in vintage surfboards and baseball bat sized necks where sufficient area is available to compensate for the inherit weakness of this technique.

The way to determine which side of the glue joint failed is to look into the break and check which wood displays tear-out - if both the rosewood and maple joint faces are clean separations - you have a glue problem - if you have tear-out /splinters attached predominantly to either surface, you can work out which timber glue joint failed first.  

Regards, Rusty.   

[Kerry Krishna]

 Yep, I knew about all that Russel, What I was asking though, is if a whole bunch of these necks were laminated like this. As I see it, this construction , as it is just would not stand any test of time without the crossgrained front and back plate tying it together is all. 

[Russell Vance]

I see;   the answer is no.   This sort of dissimilar stringer is a cosmetic and quite uncommon in modern electrics - I recall there was a few around in the 70-80s but rare on commercially produced guitars.   Head stock thicknesses are also usually around 12-14 mm (depending on your brand of machines) and this one looks a bit skinny.   As a rule backplates are not used in electrics as they don't look so good on a maple neck due to blend problems.  A good strong faceplate is always a good thing.

The rest is, as you say, just adding to the knowledge base so this bloke can move down the road a bit with his building.  

 Regards, Rusty.  

[Rob Gray]

I have only made two in this fashion with the M/R/M/R/M lamination. This was before I read some articles on Gibson mando necks delaminating on Frets.com. I do not practice this currently, but, as I have two guitars close to complete for myself with this construction, I wanted to finish them. Now I do a center joined two piece neck (no stringers) for set-neck or neck-thru construction. For bolt-on it's one piece, ala fender, or scarf joint. Set or thru necks have a ebony head-cap.

The headstock is right around 1/2". I peeked in the joint with a light and there is no visible tear out. I believe this failure is attributed to me not applying enough glue or over clamping.

I will just bite the bullet, epoxy the thing, put a headcap on it, and refinish the headstock. I'll post pictures once I fix it.