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Does anyone have a good technique for gluing up V joints?
Thanks

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Jim Watts
http://jameswattsguitars.com

I used to clamp a cross stick to the neck and use rubber bands to pull the head in. The issue there was that if you somehow got the bands pulling 'up' or 'down' the shoulder of the tenon would be slightly open on the bottom or top side.

These days I clamp the neck in the vice so that the head will be pointing straight up, and do a rub joint with hot hide glue. Warm (NOT hot) the surfaces, slather on a generous amount of fresh hot glue, put the head on, and rub it up and down a few times with a little pressure to push out the excess glue. When you feel it start to grab you slide the head into position and walk away. Leave it for a couple of hours at least, and over night is better.

This is a compression joint, with the sides of the tenon in shear. It's inherently strong, since the string load is pulling it together and producing more grip force on the tenon. The fact that it's at least partly end grain doesn't hurt it too much under normal loads. Still, you want to get a tight joint, if only for cosmetic reasons. IMO the reason we clamp glue joints is mostly to pull them into line, get out excess glue, and hold everything in position while the glue sets. You're not really trying to force glue into the wood under pressure, but just to get the surfaces as close as you can with a bit of glue in between. In this case (and in most of what we do) the fit of the joint should be a given, so all you really need to do is see to it that the surfaces are well wet with glue, and then get the excess out.Rubbing does that very nicely. I've been using rub joints for years for plate joins in arch tops and fiddles with no problems. So that's the deal; get the excess glue out and line the joint up before the glue gels, and then don't touch it until the glue has pretty well dried out.

This should work just as well with Titebond; O've never tried it but will soon. One advantage of using hide glue is that it's more brittle, particularly in shock. The biggest problem with heads is that they get knocked off. With a one-piece or laminate neck and head you've got wood breakage to deal with. On a V-joint glued with hide glue the shock breaks the glue line, rather than wood, so the repair is easy.

This happened to a friend of mine who loaned his guitar to a student for a class, and left it standing on a chair rather than interrupt him erasing the blackboard. It fell on the head. He swept the parts into the case without looking too closely, and was at my shop door the next morning when I unlocked it. All the broke was the glue line. Since it was HHG all I had to do was wash it off with warm water, put on some more glue, and line it back up. It's been fine for 20+ years, so far as I know.


Aside from the greater likelihood of wood breakage, Titebond doesn't really stick to itself well. To get a good bond you need to get all the glue off the surface, which always results in removing at least some wood. In a V-joint that compromises the fit, and in itself weakens the joint. I'm working on a 'vegetarian' guitar, so the use of Titebond has been specified. I'll just have to hope that the head never gets knocked off...

Are V-Joints done on steel strung guitars?

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Hutch

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

Not usually, but no reason they couldn't be.
Steel string guitars have been factory productions for the most part. Factories valued expediency above material savings when raw materials were cheap, so 1 piece necks were often (but not always) the norm. Aside from gluing on "ears" for pegheads or multipiece laminations that were then bandsawed out as a "one piece" neck, it was less common to see glued on heel blocks, and separate pegheads.

Thanks Alan,
I was wondering if a rub joint with HHG would work. I've mocked up several clamping arrangements and they all seem to have the problem of potentially tipping the shoulders as you point out.
Hutch - I pretty sure Martin started out using v-joints way back when and the vintage diamond volute is a form of v-joint. My guess is modern diamonds are carved on during the cnc process, I don't really know though.
But, I'm building a classical with this v-joint.

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Jim Watts
http://jameswattsguitars.com

The 'through' V-join, which is what I've used, was pretty much the norm for guitar heads for centuries. It works just as well on steel strings, including 12s, if you make the V large enough and fit it well. That repair for the friend was actually on an archtop.

The joint that Martin used up until sometime in WW 1, was a modified bridle joint. It's a bit hard to describe using ASCII text. It looks like a through V-joint when it's done, with the major tell-tale being that the diamond has to be proud of the surface of the back of the head. On a through V-joint you can level the back of the headstock, and that's normal of classical guitars. The Martin style bridle joint can actually be cut using a table saw, which you can't do with a through V, with the bridle only requiring a bit of hand fitting with a plane at the end. It's a nice joint for the level of production they had at the time.

Those Martins were all designed for gut strings, of course, and my understanding is that they used cedro for the neck, which is lighter and softer than mahogany in general. I suspect they switched over to the one-piece neck when mahogany became available in large enough sizes at a reasonable cost, and the balance with labor costs tipped in it's favor. They retained the 'dart' as a design feature even though it has no real function.

Another type of "V" joint used by Hauser was the "covered V". The mortice didn't come through the face of the headstock and the V had an angle cut into the sides like a dovetail that in combination with the "cover" locked the joint in place. This also allowed the peghead to not require a face veneer and the join line was hidden under the nut on the front of the guitar. It requires more skill to do well and you don't see it used much today. A similar outcome could be had by angling the sides of a through V and then gluing on a face veneer.
David Schramm has an excellent pictorial explaining the different V joints:
http://schrammguitars.com/vhead.html

I glued the v joint on my arch top, and my baroque with a rub joint. It seems to me that the joint works nice with a 10 degree tilt, with the 20 degree tilt on the Staufer I'm doing, it doesn't seem as good; the notch disappears fast. I switched it around to put the v on the head because I want to make the head in layers with the integral tuners, and the v notch would get in the way. It is also like a modified scarf joint. The fingerboard will sandwich the v in on top. I made a mock-up, but it's not done. I'll see how the mock-up in some scrap poplar does. I think it will be fine. It would be easy to make with a mill.
If it doesn't seem strong enough I could tilt it to 15 degrees. I didn't draw that out to see the difference.

I notice my mistakes in photos. I can't see them otherwise! The veneer joints aren't great, and the nut needs to be trimmed. A little chip in the veneer too.

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Why be normal?

Hi Ken,
If you are going to make the joint that way you may find a square sided ramp will give you more gluing area rather than the "V" shape, and be easier to fit. I have joined dulcimer pegheads that way - the fret box is hollowed out along it's length so slipping the end of the peghead into the dado seemed a logical way to join them together.

On the original style neck they moved the V joint further down the peghead/neck, but still kept the V on the neck portion and used a "covered V":

I guess I should have looked at that photo closer. I never thought about moving the vee down the neck. Thanks Clay; I'll just do it the right way. Doing instruments from photos, and rough working drawings is not the same as a good drawing/plan, and seeing the original in person.

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Why be normal?

Jim,

Here's a scheme I worked out. There's a bench dog on the vise jaw at the base of the neck blank at the right. For the dog on the left, I set the height of the collar that's clamped to the dowel so that the head stays at the proper angle.

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formerly known around here as burbank
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http://www.patfosterguitars.com

Pat,
I was playing around with my bench vise and a block as a stop for the head, basically the same setup as you show without the post and collar. It seems like it'd work pretty well but I can see it being tricky to get the head set right while gluing. You post and collar looks absolutely brilliant. Thanks for sharing.

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Jim Watts
http://jameswattsguitars.com

Jim,

I set up the post and collar in a dry setup to get the height of the collar right. One gotcha is to make sure the neck shaft stays in good contact with the bench. No problem with the head: the force from the collar ensures that the head keeps it in contact with the bench. Good luck!

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formerly known around here as burbank
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http://www.patfosterguitars.com

Pat, I used this concept earlier this afternoon, although I just clamped a block as an angle guide to my other block. Like you state I set the position in a dry fit and checked it for repeatability a bunch of times, which was excellent by the way. I was able to brush on some HHG and geter clamped up in about 30 seconds or so.
Thanks once again.

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Jim Watts
http://jameswattsguitars.com