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Tips on cutting a diamond volute?
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Author:  jfmckenna [ Sun Jan 09, 2022 1:29 pm ]
Post subject:  Tips on cutting a diamond volute?

This will be a first for me. I am going for the prewar style 45 volute.

I'm going to try and follow Bruce here: https://umgf.com/carving-the-martin-volute-t136217.html

But I'd love to hear any tips from those who have done these. Any snags you run into and so on.

I'm thinking that when I cut out the one piece neck I need to leave the headstock as thick or slightly thicker than the height of the diamond. Do I need to make the neck thicker there too?

Also the little shoulders under the nut look a bit tricky too. Over all it looks like one little mistake and you are starting over again.

Regards.

Author:  Pat Foster [ Sun Jan 09, 2022 3:53 pm ]
Post subject:  Re: Tips on cutting a diamond volute?

Here's a pic of one I did.

http://www.patfosterguitars.com/opus/large-21.html

There's a few other pics before and after this one, but not much on the process.

Author:  J De Rocher [ Sun Jan 09, 2022 6:16 pm ]
Post subject:  Re: Tips on cutting a diamond volute?

The volute I put on my necks is modeled after the one on my HD-28. The dimensions and location relative to the nut are shown in the photos below, if that helps. These dimensions can be adjusted a bit as needed to blend the volute into the neck shaft and the shoulders of the headstock.

Attachment:
Volute top view.jpg

Attachment:
Volute side view.jpg




The volute on my Martin is pretty small (only 1/4" tall at the peak) so you don't need to leave a huge amount of added thickness in that area on the back of the headstock when rough cutting the neck shape out of the blank. Leaving 1/2" extra thickness gives plenty of room for carving the volute. How thick the neck needs to be directly under the nut depends on where you position the start of the curved side of the volute.

Attachment:
Neck profile - rough cut.jpg



The approach I use to carve the volute is similar to the one in the photos in the link you provided. In my case, I use a Safety Planer to thickness the headstock, but I also leave a block at the volute location to carve. I do all the carving of the volute with a 1/2" chisel and then finish it off the flat sides of the volute with adhesive backed sandpaper on small sanding blocks (aprox. 1" x 3"). The curved face of the volute is carved with the chisel and then gets fine tuned with adhesive-backed sandpaper on a 1/2" dowel.

Attachment:
Volute carving.jpg



One snag I've run into is that sometimes the wood will only let you carve the flat sides of the volute in one direction but not the other. That is one place you could make a mistake you might not be able to recover from if you're not watching out for that.

Blending the lower corners of the volute into the headstock-to-neck shaft transition and shaping the shoulders is a bit of a challenge for me, but I don't think it's easy to make a mistake you can't adjust for. The particular shape of your headstock may make it easier or harder to do the transition though. I use the 1/2" chisel to rough carve the shoulders and transition, and finish shaping with riffler files.

Author:  jfmckenna [ Mon Jan 10, 2022 8:23 am ]
Post subject:  Re: Tips on cutting a diamond volute?

Those look great you guys. Jay that's about the exact dimensions as what I am going for too.

I'm thinking about jigging this one up and got started with this.

Image

Author:  Woodie G [ Mon Jan 10, 2022 10:02 am ]
Post subject:  Re: Tips on cutting a diamond volute?

A few older shots of the jig we used to thickness the peghead and mill the rough dart or transition area on non-dart necks. The neck blank is held in position with a couple of screws through the bottom of the fixture into the slotted headstock waste or future tuner hole for solid headstocks.

Here's the fixture that holds the neck with the jig plate attached. We had three different plates for six strings - Martin dart, smile volute/18-style transition, and a straight thicknessing plate to free-rout.

Attachment:
Volute Mill 1.jpg


Attachment:
Volute Mill 2.jpg


Keep in mind that the direction of pass must be considered when thicknessing the peghead due to the grain run-out in a one-piece neck.

Also worth mentioning that a 1-3/4" or 2" American pattern butt chisel or other shorter-bladed, wide blade allows the two beveled surfaces of the dart (or volute) to be shaped, but any wide, single-bevel chisel is handy for the task.

https://toolsforworkingwood.com/store/item/IL-100-20.XX

Author:  johnparchem [ Mon Jan 10, 2022 11:36 am ]
Post subject:  Re: Tips on cutting a diamond volute?

I do it just like Jay in terms of cutting out the blank and using the safety planer to both thickness the peg head and rough out the volute. We may have been influenced by the same luthier. From there I use a chisel to flatten the top of the volute and create most of the longitudinal slope. With a flat top I draw in the volute profile and the center line. With a chisel I square the edges to the profile lines establishing the base. Then it is easy to use a chisel to create the facet from the base to the center line. I just roughed out one this morning. In the picture you can see Jay's photo. I was pretty close to his measurements.

Image

Author:  Freeman [ Mon Jan 10, 2022 12:29 pm ]
Post subject:  Re: Tips on cutting a diamond volute?

I did one as an add on. Almost all of my necks are multiple piece with scarfed heads.

Attachment:
IMG_0942.JPG


Attachment:
IMG_0959-1.jpg

Author:  jfmckenna [ Mon Jan 10, 2022 1:55 pm ]
Post subject:  Re: Tips on cutting a diamond volute?

Than you all for the replies. Woodie that is pretty close to the jig I was envisioning.

Freeman! I like that. In fact for these 3 guitars I am building I had already started on the 3 necks when we decided we wanted to go for the dart/diamond. Since I had them already thicknessed I would have to start over. No big deal but this method could be a time saver.

I mean in the end no matter what these diamond/dart volutes are really just faux volutes anyway right? They don't really have any structural purpose like the birds beak joint that they 'pretend' to be. Unless of course you do think that they do offer some structural properties?

So My question Freeman is, do you do your best to match grain and does it look real good to your eye? Can you tell in any way at all that it is glued on? That still might be acceptable but would have to talk to my client. But I like the idea.

Author:  Freeman [ Mon Jan 10, 2022 7:25 pm ]
Post subject:  Re: Tips on cutting a diamond volute?

jfmckenna wrote:
So My question Freeman is, do you do your best to match grain and does it look real good to your eye? Can you tell in any way at all that it is glued on? That still might be acceptable but would have to talk to my client. But I like the idea.


I can barely see the glue line on the scarf joint but not on the dart. It was a scrap from the same blank that I made the whole neck out of, I didn't spend any extra time matching grain or anything. Light red/brown stain but no attempt to hide it

Attachment:
IMG_7253-1.jpg


Think about it, if you had done a true birds beak you would have a seam plus possibly two different pieces of wood. And you would be proud of your worksmanship.

Author:  jfmckenna [ Mon Jan 10, 2022 7:41 pm ]
Post subject:  Re: Tips on cutting a diamond volute?

Good point! Pun intended :D

Yeah I think I may just give it a try. Worst to worst I can just remove it. I do still have the rest of the one piece block too so I actually can cut the piece right out of that and it would be identical.

Author:  jfmckenna [ Tue Jan 11, 2022 10:25 am ]
Post subject:  Re: Tips on cutting a diamond volute?

Testing out the jig on some pine it seems to work. The diamond as it turns out is not so much the hard part but getting those shoulders perfect is tricky.

Image

Image

Image

These cuts look difficult to get perfect. One slip and the whole thing is off.

Image

Author:  Clay S. [ Tue Jan 11, 2022 12:23 pm ]
Post subject:  Re: Tips on cutting a diamond volute?

If you have a table saw, tenoning jig, and small router, the modified bridle joint (bird's beak) is in some ways simpler and requires less hand skill to cut than milling and carving a dart on a one piece neck. In addition, it allows you to work the peghead and neck shaft separately and join them in final assembly. Although some hand work is required, most of it can be accomplished with a small dovetail saw.

Author:  jfmckenna [ Tue Jan 11, 2022 2:54 pm ]
Post subject:  Re: Tips on cutting a diamond volute?

I don't hae a table saw. They scare me frankly :)

But I am surprised to hear you say you think it's actually easier. I have never tried one though I have repaired several on vintage Ashborn's and the like and have always marveled at the skill of those luthiers of the past.

Author:  Clay S. [ Fri Jan 14, 2022 12:44 am ]
Post subject:  Re: Tips on cutting a diamond volute?

jfmckenna wrote:
I don't hae a table saw. They scare me frankly :)

But I am surprised to hear you say you think it's actually easier. I have never tried one though I have repaired several on vintage Ashborn's and the like and have always marveled at the skill of those luthiers of the past.


The joint looks more complicated than it is. It is mostly a series of saw cuts. If you are good with a backsaw you can lay it out on the neck shaft and cut it with that. I take the easy way out and use the tablesaw. I will try to draw it out and post it.

Author:  Clay S. [ Fri Jan 14, 2022 1:59 pm ]
Post subject:  Re: Tips on cutting a diamond volute?

Hi J.F.
Here is a drawing showing the basic cuts used to form the bird's beak joint as used by Martin in the past. Some of the cuts can be varied somewhat but this is one of the simpler ways to do it and still have it made close to the originals. Some smoothing and refinement of the saw cuts is needed to finish it off but no more than is required to shape and fit the peghead. Most of the milling and shaping of the neck and peghead can be done while they are apart which has some advantages.
As I mentioned before, I do much of the work with machine tools and have made a few simple jigs to aid in the process, but those same things can be done with hand tools.

Author:  Clay S. [ Sat Jan 15, 2022 11:08 am ]
Post subject:  Re: Tips on cutting a diamond volute?

The drawing above will give a longer narrower dart similar to the Martin peghead posted above. For a wider dart you can modify the cuts some, which may better suit the flatter neck profiles commonly used today. A wider dart may allow you to square off the sides of the stub tenon (making cutting the peghead recess quicker and easier) without too much loss of gluing surface. Another thing which is sometimes done is to shorten the stub tenon so it doesn't encroach into the slots on slotted pegheads. On some of the originals it does encroach but is not noticed unless the joint is disassembled.
I would encourage people to try the joint on scrap before attempting it on the work piece to see what modifications you may need to make with your particular neck and peghead style.

Author:  jfmckenna [ Sun Jan 16, 2022 11:06 am ]
Post subject:  Re: Tips on cutting a diamond volute?

I'll have to try that out on some pine when I get a chance...

Author:  Clay S. [ Sun Jan 16, 2022 12:00 pm ]
Post subject:  Re: Tips on cutting a diamond volute?

I Goofed!
On the drawing of the shortened stub tenon (sometimes used on slotted pegheads) I drew the sawcut the wrong way. It should create a wider mouth opening:
Attachment:
modified bridle joint 3.jpg


Hi J.F.,
Doing a mock up in pine I think is a good idea. The old Martin guitars used a fairly tall "V" neck profile that lent itself to the cutting of the joint. The more modern "flatter" neck shapes may require a little adjustment of the cuts, but allow the use of slightly thinner stock.

P.S. One other thing I could mention - the peghead "ramp" angle is the same as the peghead/dart angle if the joint is cut as in the first drawing. With a stubbed tenon the angle of the opening would need to be used.

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