Cutting the birds’ beak/ dart/ volute

[Splinters]

I mean the actual joint at the neck and headstock. I’ve looked at all the pictures I can find of this. I’ve practiced several joints on scrap. I’ve nearly got it figured out.
It seems I can cut this quickly and accurately with just a tennon saw. The difficult part for me is not the dart or the tennon, it’s the Vee in the headstock part. It’s not that hard to mark off, but it’s hard to hold it and clean it out.
I can cut the slopes on the sides of the tennon with the saw, but it’s hard to get the flat on the bottom of the tennon cleaned out because it goes to a point at the back. You can’t really chisel it out from the end of the headstock because you are climbing into the grain when pushing the chisel.
Any advice on this?

[Alan Carruth]

Are you taking about the original through V-joint, as used in many Classical guitars, or Martin's modified bridle joint? The Martin-style joint can actually be cut with jigs on a table saw, with only a bit of fitting needed at the end. The through V-joint is harder to do, although it might be possible to set up a shaper table for it using custom cutters. Doing it by hand is simply a matter of taking your time fitting, and keeping your tools really sharp. I usually stop a few times to touch up my chisel, especially when doing that climb cut into the point of the mortice. I think my record for cutting one of these is 45 minutes; usually it takes longer.

[Splinters]

Yes, the through vee joint. I just want to do it because I haven’t done it before.
It certainly is a clever joint, and very strong even without glue.

[Alan Carruth]

I would not try to string up a guitar with a V-joined head unless it was glued on, but, that said, it is loaded in (mostly) compression and shear, which are the 'good' ways to stress a glue line. The bridle joint could hold under string pressure with no glue if it was fitted right.

[sgonwa]

John Grevin shared an article in an issue of the Guild of American Luthiers on the building of this joint. Excellent article with step by step instructions and photos for each step. The issue is titled Flattop Guitars: An American Lutherie Anthology.

https://luth.org/books/american-luth...rie-anthology/

Steve

[printer2]

Bruce Sexauer has showed pictures of how he does it in the Custom Shop, a few years ago I think.

[M Pete]

Originally Posted by Alan Carruth

Are you taking about the original through V-joint, as used in many Classical guitars, or Martin's modified bridle joint? The Martin-style joint can actually be cut with jigs on a table saw, with only a bit of fitting needed at the end. The through V-joint is harder to do, although it might be possible to set up a shaper table for it using custom cutters. Doing it by hand is simply a matter of taking your time fitting, and keeping your tools really sharp. I usually stop a few times to touch up my chisel, especially when doing that climb cut into the point of the mortice. I think my record for cutting one of these is 45 minutes; usually it takes longer.

Alan, this has actually been my latest obsession this past week while I wait for lacquer to cure. I actually really like how the wood grain transition is right at the headstock transition instead of along the neck or somewhere in the headstock. Figuring out different ways to do the Martin joint. I have been doing some CAM models looking at it and was thinking that the neck portion could easily be done with a tenon jig (which I picked up recently) on a table saw and router templates. My plan is to have a rounded portion instead of a point at the end so that I can get a router bit in there. More of a wide based "U" instead of a "V".

Cole Clark in OZ has an interesting method which in kind of like what I described, but no volute at the bottom. I think that allows them to use a clamp on top and bottom of the headstock for glue-up.

Would you mind showing some pictures on how you do it? Or a video link?

[M Pete]

Here are pictures of a CAD I did for how I think Cole does it. You can route out the motrise on the headstock piece flat and then use a tenon jig on a table saw to put the headstock angle on the neck stock and rout out the tenon. You could also use a CNC for all of it, which is what I think Cole does. In that case I'd put a small fillet on the edges of the tenon where it meets the body so that your bit can clean all of that out, replicate on the mortise side as well.

Of course then if you want to have a volute then you leave the stuff on the bottom as below. Either way I think it would be much easier to work the headstock angle into the neck tenon than the headstock mortise if you are not using a CNC or want to build an angled platform for a router.

[Quickstep192]

Originally Posted by M Pete

Here are pictures of a CAD I did for how I think Cole does it. You can route out the motrise on the headstock piece flat and then use a tenon jig on a table saw to put the headstock angle on the neck stock and rout out the tenon. You could also use a CNC for all of it, which is what I think Cole does. In that case I'd put a small fillet on the edges of the tenon where it meets the body so that your bit can clean all of that out, replicate on the mortise side as well.

Of course then if you want to have a volute then you leave the stuff on the bottom as below. Either way I think it would be much easier to work the headstock angle into the neck tenon than the headstock mortise if you are not using a CNC or want to build an angled platform for a router.

When you say how Cole does it, do you mean Cole Clark? I’d love to learn more from your research.

[M Pete]

Originally Posted by Quickstep192

When you say how Cole does it, do you mean Cole Clark? I’d love to learn more from your research.

I saw the video below linked to another thread and you can see some of the process from 0:36 to 0:55. They use a 5 axis CNC which makes it much easier, but clearly put the headstock angle on the tenon (neck) instead of the mortise (headstock). It is much easier to do it that way if you are going to use a table saw and router. To me it looks like some of the necks have volutes and some do not. All of the ones in the bin at 0:55 have one though. That part is easy to adjust to what ever shape you would want.

https://www.youtube.com/watch?v=qFlA1X-EZ7w

[Quickstep192]

Originally Posted by M Pete

I saw the video below linked to another thread and you can see some of the process from 0:36 to 0:55. They use a 5 axis CNC which makes it much easier, but clearly put the headstock angle on the tenon (neck) instead of the mortise (headstock). It is much easier to do it that way if you are going to use a table saw and router. To me it looks like some of the necks have volutes and some do not. All of the ones in the bin at 0:55 have one though. That part is easy to adjust to what ever shape you would want.

https://www.youtube.com/watch?v=qFlA1X-EZ7w

Thanks for the info. I can see how the headstock could be routed, but how would you envision doing the neck part without CNC equipment?

BTW, here’s a picture that shows the joint with contrasting woods that shows the joinery. Cool look too…

[M Pete]

Originally Posted by Quickstep192

Thanks for the info. I can see how the headstock could be routed, but how would you envision doing the neck part without CNC equipment?

You mean for the tip of the tenon V/U? I'd make a template out of plywood. After you cut the headstock angle attach the template to the angled part and lay that flat on a router table using a bit with a follow bearing. Between a table saw with a good miter fence, a tenon jig, and a table router you should be able to do it. Probably much faster than the CNC too, unless you are doing more than one at a time.

[Quickstep192]

When I took a close look at the tenon (neck part), it looks like there’s a bevel on the face side. Assuming there’s a similar bevel on the peghead part, that would help lock the joint kind of like a dovetail.

Sorry if I’m being a pest, but I’m still not clear on how you’d make the tenon at the top of the neck part. Assuming the template would be attached to the part that remains after the cut, there’s not a lot to attach the template to given that the widest part (nut area) is only 1-3/4” or so.

BTW, it would be really cool the make the cuts using a dovetail bit.

[M Pete]

Originally Posted by Quickstep192

When I took a close look at the tenon (neck part), it looks like there’s a bevel on the face side. Assuming there’s a similar bevel on the peghead part, that would help lock the joint kind of like a dovetail.

Are you referring to the picture you posted three posts up? If so that volute sits on the bottom of the headstock portion and they carved the bevel there afterwards I would imagine. They don't cut all the way through the headstock with the mortise

Originally Posted by Quickstep192

Sorry if I’m being a pest, but I’m still not clear on how you’d make the tenon at the top of the neck part. Assuming the template would be attached to the part that remains after the cut, there’s not a lot to attach the template to given that the widest part (nut area) is only 1-3/4” or so.

I'd make it a jig with a wide base. If you were doing a 13 degree headstock angle, use a 13 degree wedge for the neck to rest on upside down. That will put he top of the tenon flat on the router table and you can go from there. You could make the wedge portion adjustable so you can use the same jig for any headstock angle.

[Quickstep192]

Here’s a picture showing what looks like a bevel to me. What do you think?