A few questions about early martin necks.

[Francis Beaulieu]

Hello everyone,
I'm in the early stages of my first guitar project for the last 5 years. I want to make a small guitar, strongly inspired by the small, early Martin guitars of the late 19th century.

Right now I have a few questions about the neck. Does anyone know the thickness of those early necks? (preferably without the fingerboard). I'd also need the thickness of the headstock, and some hints about the neck profile would be great.

I'm not too obsessed about the exact measurements and everything, since I'm not interested in making an exact replica, and I've never even seen one of these guitars for real, but I just want to get an idea of the dimensions, so I can start drafting my plan. By the way, is there any plan for these guitars? I already have the size 5 by Scott Antes I think, but I'm mostly interested in the 2 1/2 size.

Many thanks,

Francis

[Francis Beaulieu]

Nevermind, I just found the GAL plan...

[Clay Schaeffer]

Hi Francis,
The two GAL Martin parlor guitar plans I could find show a guitar from the mid 19th century and one from the early 20th century. The necks were made differently than they were in the late 19th century . In the late 19th century they used a modified bridle joint to attach the peghead which showed the "volute" on the back of the neck. The neck profile was more of a "V" shape which worked well with this joinery method.

[Francis Beaulieu]

Yes, the peghead joint is not the same, and I am looking for the bridle joint, but it's still a good starting point. I'd also appreciate some details on that joint. I've seen the pictures on Frank Ford's websites, but some more info and numbers could help a lot.

Thanks,

Francis

[Michael Lewis]

The true bridal joint is a rather complicated bit of joinery to start out with. I suggest the V joint, which is a simplified version and still pretty strong if well fitted.

[Clay Schaeffer]

I make the bridle joint using a few simple jigs, a table saw, router, and a little bit of hand work. It is essentially a "bird's beak" wrapping itself around a "ramp". I once did a photo essay on my method, but I don't know if it ever made it into the library. What measurements would you like?

[Francis Beaulieu]

While I don't have much recent guitar-making experience, I'm actually making a living as an early bowed instrument maker, so I do have a lot of experience, and I'm not much scared by this complex joinery. I'm actually quite excited to try it.

Clay, I will photo essay. I found another one on the net, by John Greven, but it seemed slightly different than the pictures I saw on Frank Ford's website. John Greven cuts the "diamond" portion and the "hidden" portion (I don't have a better name...) at the same time, and so they are the same width, while the pictures on Frank Ford's website suggest that the "hidden" portion is wider, with a "front-to-back" taper in width, in addition to the V shape (I hope this is clear...)

Anyway, I was asking for measurements but I'm not even sure what I need. I think I have found enough pictures to just draft it for myself and try it. I'll let you know how it goes.

Maybe one last thing: what is the thickness of the neck blank you start with? (to have enough wood for the diamond, I mean)

Many thanks,

Francis

[Clay Schaeffer]

Hi Francis,
Greven's method doesn't leave as much wood on the hidden tenon, so may not be as strong as the original. The original joint was cut by hand, and the saw cut - across the neck shaft- was angled,which made the sides of the tenon and the volute on the back of the neck form a "V". This means the recess in the peghead cut for the tenon must also have a matching angle.
I use a slightly different method with a straight sided tenon that mates with a straight sided ramp that is routed into the peghead. It allows the hidden tenon to be larger and is easier to fit.

[Chuck Tweedy]

The Martin "diamond volute" joint was covered extensively in issue #102 of American Lutherie (Summer 2010). Greven wrote up his method in half the article, and Charles Freeborn wrote up his method in the other half. It's a great article.

[Clay Schaeffer]

Hi Chuck,
Can you describe Charles Freeborn's method?
The traditional joint is done with simple straight saw cuts to form the "volute" and "birds mouth". The recess in the peghead is the place where some fitting is required. I will try to do one in the next few days and post some pictures.

[Chuck Tweedy]

Hey Clay,
Now that I look back at the article it is a bit complicated because Freeborn describes 3 separate methods to do the joint. One using a bandsaw and jigs, one with a table saw & jigs, and the final is by hand. Prior to that Greven showed his method using bandsaw (for the neck-shaft work) & router (and jig - for the headstock part).
Sorry, but I can't describe all 4 methods
You know this beast Clay - I'm sure you can imagine - in general - how they all work.

[Clay Schaeffer]

Here is a way to cut the traditional bridle joint as used by the early Martin guitars.
First layout the saw cuts on the end of the neck blank. The "triangle" cuts form the sides of the diamond and the sides of the hidden tenon. The angle cuts on the side of the blank form the birds mouth.

[Clay Schaeffer]

The angled cuts on the side of the neck determine the peghead / neck shaft angle. I used 11 degrees. I use a jig to cut a matching "ramp" in the peghead. With the traditional joint the sides of the ramp have to be angled to fit the sides of the neck tenon. I did this with a chisel and a bit of chalk fitting. This is probably the most difficult part of the joint.
The neck shaft is rounded and the diamond partly removed to create the "flat" section toward the neck.

[Clay Schaeffer]

As the peghead is put in place the peghead mortice and bird's mouth will mate for a snug fit. The peghead veneer covers the upper part of the neck tenon and provides some additional gluing surface.
If slots are cut for the tuners the neck tenon will be exposed in places, so a good fit is necessary. I believe Martin truncated the tenon a bit to minimize this, but if you study the photo's on Frank Ford's site (Frets.com) you will see a slight opening where the tenon breaks through in the "ramp" area of the peghead.

[Clay Schaeffer]

I'm hoping the pictures explain things better than my words have done. I will be happy to answer anyone's questions as best I can.

[Chuck Tweedy]

Clay, That is pretty much exactly how Freeborn did his "all handsaw" method.

[Francis Beaulieu]

Great! Thanks for the pictures.
I was wondering whether should poke through the slotted peghead or not, so thanks for that info.
I'll make mine next week, I'll let you know how it goes.