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This might seem elementary but I'll ask anyway. Is there a tutorial out there anywhere on making a backstrap for neck?I've seen some really cool ones on old banjos(multi layers) and modern guitars and was wondering what was involved with creating that.Do you have to bend the laminate and glue up to the preformed valute or is there a method I should know about.
Chance

Is this what you're talking about?


It's 5 pieces of wood glued together. It was built in a big block and 2 necks made from it.

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

Here's one i'm finishing up on right now.It's a 3 piece laminate with a small volute.

Hi Woody & Mark,
Actually I'm referring to the veneer on the back of the head stock. It would be like the headstock veneer on the face of the peghead but on the back, blending into the volute.
Chance

I think you mean this, correct?



If it is, I have never had to prebend the laminations but the thickest I have done is in 2 pieces and totalled about .05. I glue it on before I shape any of the volute area but pay attention to how much thicker it is there than your neck will end up at, sometimes it can become a very angled area and can look a little weird. Also, pay attention to where the angle starts as you want your tuners to be on a flat part of the headstock. Some of these (like the banjo ones you mention) do not have a volute and in that case you would shape the neck in one plane, or more accurately you would thickness the neck so it was flat all the way down the back and into the headstock. Then you would add the veneers and when you shaped the neck to your v or c shape the laminations would show on the sides. Hopefully Howard Klepper will chime in, he has some beautiful examples of this on his website.

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Burton
http://www.legeytinstruments.com
Brookline, MA.

Here's an example on a vintage banjo

Burton,
Yes, that's the ticket. That's actually a better example than I just posted. I just don't get it. I guess I can't visualize the process. That's why I was hoping to find a bit of a tutorial.
Chance

Chance,

Imagine that the example that Woody posted has the neck shaft thicknessed so that in the middle it is as thick as it will need to be and when he carves it he will just be shaping the sides. Now he would glue his veneers onto the headstock and down the neck maybe halfway. Then, once he shapes his neck the only place the veneer is not carved away is in the middle and on the headstock, as on the banjo example you posted. Does that help?

Actually, I just found this too on Frets. Not exactly what I am describing (the neck is already shaped and he is using a thicker backstrap veneer) but pretty close.
http://www.frets.com/FRETSPAGES/Luthier ... erlay.html

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Burton
http://www.legeytinstruments.com
Brookline, MA.

Burton,
Thanks for the Frets link. That was a good visual. So, if I under stand it right, I would need to bend the veneer slightly(to follow the shape of the potential volute) and glue it to the back of the peghead just past the volute area. Then shape the neck up to and including the volute. Unless of course I use a very thin veneer(s).
I'm after something like this:



Chance

Yes, although i have never had to bend it. I believe he was using an extra thick backstrap (.15?) to strengthen the headstock. Most are .06 or less and are easily forced into shape with clamps. You will know once you try to clamp it. If it just won't go, give it some heat.

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Burton
http://www.legeytinstruments.com
Brookline, MA.

Thanks everyone for the reponses. I believe I understand it now. Probably a lot easier than I was anticipating. Off to the bench.
Chance

I do my backstraps with veneers and a vacuum bag. In order to do the "banjo style" backstrap, you have to drum sand a small radius into the back of the neck so that the veneers will bring the backstrapped part of the neck up to the same level as the rest of it. It needs the radiused transition to make it look right when it's finished. Here's a couple of pictures of the vacuum bag process and what it looks like after carving the neck.

With veneers, there's no pre-bending involved. If I need an extra thick backstrap, like maybe 1/8", I do it with multiple layers of thinner veneers instead of bending a thicker one.

Dave

Here's a side view of the veneers that will hopefully make a little more sense out of what I was trying to say in the earlier post. Where the backstrap goes, you thin the shaft of the neck and make a smooth transition into the peghead. When you add the veneers, the thickness of the shaft comes back up to where it originally was. The radius at the end of the backstrap makes a smooth transition into the neck with the distinctive stripes.

Dave

Dave that looks great. Do you have a fixture set up for the drum sanding portion?
Thanks,
Mike Fleck

Thanks Mike. In the past, I had a jig for the backstrap--just a pattern following jig on my oscillating sander. But I've found it's just as easy to freehand it, so that's what I do now, using a 3" drum on my spindle sander. Usually I put the backstrap on while the neck blank is still completely square, but on this particular one the backstrap was an afterthought, and the rough profile of the neck was already cut.

Dave

Thanks for the pics Dave. The vacuum idea is a great one. What type of glue would you use with that? And how about cure time. Also, is there a source for that vacuum system or is it home made? Thanks again for weighing in on this.
Chance

I use epoxy on my necks--either West or System 3 for lamination. As for the vacuum system, it's shop made based on the venturi-type plans from Joe Woodworker. It works great for vacuum bagging and for general vacuum hold-down on jigs and was pretty cheap to build.

As for cure time--it depends on temperature, but I typically leave the bag under vacuum overnight. Probably overkill, but I'm asleep then anyway so why not!

Dave

Here’s how I make the “smiley” volute. I believe I’ve posted this before but I didn’t find it when I did a quick search, so forgive me if I repeat myself.

I start by sawing out a neck blank or by gluing up neck laminates.



I then true up the front of the headstock and top of the neck on the jointer or the long belt sander, which establishes the length of the headstock and fingerboard gluing surfaces.

Next, I thickness the headstock by removing material from its back on my drum sander. I stop where I want the volute to start, which is an imaginary line drawn between lower headstock "corners". This automatically creates a concave ramp that terminates the back of the headstock towards the neck shaft (remember that position of the beginning of the ramp also determines the "lowest" possible position for the tuners). The radius of the ramp is determined by my shop made sander’s Ø=150 mm drum, so it is probably “softer” or less prominent looking than many of the volutes I see other builders do.

I then bend one end of the backstrapping veneer close to the radius of the volute on a hot pipe, and glue it on with a cork faced caul with a matching shape. The front veneer is glue on at the same time, and I use pins that are located outside the finished headstock's outline to keep them from slipping (I use fish glue, so slipping isn’t so much of a problem anyways). After that I saw the headstock shape out on the band saw, staying a couple of mm outside the lines, and then it is back to the long belt sander, using the idle roller side this time, and I shape it right up to its final outline. Here’s the result so far.



From there it is mostly rasps, files and sand paper, and you end up with something looking like this.

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Rian Gitar og Mandolin

Thanks Dave & Arnt for the detailed info. You guys have been so helpful. I've been reading this forum for awhile but have been a little shy to post myself. I admire the work that I've seen from the members of this forum. You have my respect and appreciation.
Chance

the guitar i just finished had three thin veneers on the back of the peghead. no need to prebend. i just gave them a spritz with super soft the day before.
you should search the archives for a pic of a handy little clamping caul that either lance or brock posted. it uses a flat board for the large, flat surface of the back of the peghead. and then uses a bundle of 1/8" dowels held together with tape for the curved part (if you're doing that kind of hand stop/volute).
when i did mine i used 1/4"dowels because that's what i had around, and i laid them onto a layer of cork which then was placed against waxed paper and then over the veneers. worked beautifully.
phil

I found the post in the archive about the caul. I'll try this tomorrow. This is just the thread I needed to find.

http://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=17564&p=249334&hilit=+caul#p249334

Stefan