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Hello people,

I'm working on my first, a flamenco following Hernandez plans for the challenge build. I've inlaid my rosette, braced the top, joined the back and am working on my neck.
I made a solera (Courtnall style, lower bout carved out, neck extension ramped down about 2.5mm).
I was planning on using spool clamps to attach the sides and back.
I am about to bend my sides using a bending iron.
However, a friend of mine who is a steel string builder has put the fear in me saying it will be much harder to achieve a uniform shape and, as I was planning on making some kind of form to clamp the sides to after bending, I'm wondering if I should just make an outside mold that I could use as well as my solera.
Until now I was trying to avoid making a mould due to time/money/dust etc but I am now unsure what to do. I think I will use this plantilla again so it might be worth it.
I have also decided to make a 15' radius dish for bracing the back etc.
What are your thoughts? Mould or no mould?
Any advice would be great,

Will

I started out with a Courtnall-style solera, but now, for designs I'd like to build repeatedly, I devote the time to building a mold. My mold is basically a solera with fixed rather than adjustable side fixtures - you still need to establish the solera geometry somehow. I suspect mine is similar to what is described in Bogdanovich, but I didn't go back to check.

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Jim Kirby
kirby@udel.edu

It's really a matter of personal preference. I use one because I feel it results in a more uniform result and I prefer repeatability between instruments within 1-2mm. I have adapted my moulds to bolt directly to the face of the solera. The initial construction is really the issue. Do you want to invest the time and money to build them? If so then a well-built mold is a worthwhile tool. The versatility goes without speaking.. I use mine for a backing form when I bend linings and bindings. A good mold also helps when you've got some cupping or distortion from bending, to act a a plane surface to bring the sides back to true.

Good luck in whatever you decide...

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Peter

I.ve never used a mould apart from gluing a few tabs on the soundboard. The trick to going mouldless is all in bending the sides accurately and without twist. I usually do a preliminary bend, getting the shape roughly close to what it should be. I leave it for a day or so before bending again but this time aiming for greater accuracy. It's not difficult once you become accustomed to the method.

I've found that a good general rule is that if you are going to do the job more than once, build the jig/tool/fixture, because over just the two instances you'll save time and do a better job. There's very little I do just the once, even building predominantly custom guitars.

If you're building just the one blanca ever and it's for you, heck, you MUSTN'T use a mold. Who's ever seen a symmetrical real blanca?

BTW, making a mold doesn't make much dust. Now making a radius dish...

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

Solera with "adjustable mold". The supports around the perimeter allow for various situations and hold the ribs square to the top.

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http://www.booneguitars.com
https://www.facebook.com/pages/Stephen-Boone-guitar-builder/488208541257210

]Solera with blocks - less sophisticated than Stephen's. Essentially a modified Courtnall solera. I have a pair of forms, one inside and one outside. I use them when pipe bending to check my work. Recently I bent a set of BRW on the inside mold, using a blanket and slats, because it wasn't cooperating on the pipe. I like pipe bending, and didn't seem to have much of a problem with consistency, but bending on a form, while much more time involved, was pretty good.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

I want to add that the one guitar that I ever made that was truly asymmetrical and absolutely awful looking was a classical using an outside mold. It was one of my early guitars and I depended too much on the mold to hold things in position. It makes sense that an outside mold will help hold things more consistently from guitar to guitar but that is not a consideration for me. I tweak the ribs until they are comfortable in a shape that is very close to my plantilla. If the side are not exact to the plantilla but correct to each other then I accommodate the timbers I am working with. I can use the adjust ability of my solera to make this accommodation. The ribs should be in the correct shape with very little pressure to hold them there. If an outside mold and a bunch of clamps are needed to force the ribs into a correct shape then I believe that a guitar build that way will have unneeded stress built into it. Outside mold or not properly fitted ribs will make things work much better. The better the ribs are fitted the less need there is for an outside mold. This is my experience.

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http://www.booneguitars.com
https://www.facebook.com/pages/Stephen-Boone-guitar-builder/488208541257210

Hi Will,

We have a lot in common. I build mostly flamencas and I use the Santos Hernandez plantilla and the Courtnall plans with a number of modifications. Over the years I have evolved to using an outside mold, which I attach to my workboard/solera with bolts. I find this works very well for me.

Best of luck,
Max

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Max Bishop
Brighton, Michigan

Stephen an waddy nice clean vy aesthetic solera/s , mine is crude and rude and works, but I have yet to use it . I prefer the consistency of using a mold at this time . I even had the machinest make me one similiar to the alum mold used in jose oribe/s book. I am not sold on either camp yet . I have one spanish style neck that I am building for the solera, to see how that works.I am more of a fleta fan , and have the courtnall and gore plans /molds for them . am trying to keep an open mind on the solera. I can see that in the good ol days, that it must have been a low tech way for spanish luthiers to construct their guitars. So I will make 1 with a spanish heel and the solera and see how it turns out . I feel that great guitars can be built either way using a solera or mold depending on the skills and preferences of the builder.

No doubt about that!

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

I started out following Cumpiano and Natelson as my primary guide, so started with no mold and bent sides on pipe (that was for #1 and #2). Somewhere between #1 and #2, I decided to use a mold, and have switched to a bending machine to work on #3, #4 and #5. Since I need to build a form for the bender, I use the outside plywood cut-offs for the mold. Anyway a couple of pictures. Seems like I've drifted to a mold and bending machine with blanket (the light bulbs didn't work for me).
Marty

After years of building oddball instruments and tossing the mold after one use, I decided to try the mold-less method on my last guitar - as well as on my current build.

The surprising thing to me was that it wasn't that difficult to get the outline correct. With a little fiddling, the sides can be clamped directly on the line, as long as they were bent accurately. Assuming and accurate template and a sharp pencil, I'd say +/- .015" is within reason, depending on your level of OCD.

It follows that this build method might be more suited to certain personality types...

If building the same shape more than once or twice, using a mold is going to me much faster and more efficient. If I were trying to do this for a living, the mold method would win no contest.

Maybe it's just me, but I would take a close look at those fan braces and closing braces. What are the dimensions, height and thickness? How thick is the top? You are going to have a really, really stiff top. Look at Stephen's and Jim's braces. I'd say look at mine, but it's hard to tell with angle of the shot. Here is a picture of one of my guitar tops with an angle that lets you see. Center brace - tallest is 4.5 mm x about 6 mm. Outside braces are about 5.5 mm w x 3 mm tall. Closing braces are about 3x3.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Waddy,
hope I'm not diverting the thread (and assuming you're commenting on my post), but my finger braces are high with respect to yours (mine range from about 7 to 8 mm). Looks like I need to bring them down (and I was so proud of my sanding job on these two). The width on each varies from 4 to 5 mm. All my backs and tops are about 0.095 to 0.100 inch thick. Thanks for heads-up. Looks like I've got some thinning to do.
Thanks again,
Marty

Yeah, Marty, your braces are really beefy. From what I've heard in final instruments, Waddy is a good model to follow here. (Mine are probably whatever is nominal right off the GAL Romanillos plan - I haven't built enough to start deviating in an educated fashion yet.)

Waddy - a digression. One thing I have wondered about is that the closing bars on this plan seem to be so close to the linings that I wonder exactly what they are doing.

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Jim Kirby
kirby@udel.edu

Yes, they are close, but for me it works as the majority of my thinning is at the tail. I'm leaving the wings a bit thicker now. That and lighter bridges are giving me much better volume and head room.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Solera only, no mold for me, but I feel like I am in the tiny minority. As long as the sides are bent well I feel like I don't need a mold. I have always built this way and it works for me so I am loath to change. It is practical for me as well... I have built more shapes than I have fingers on my hands, so I would need an extra storage shed for all the molds I would need.

Wow! so much good advice and information. Thank you to everyone for your posts and photos, it's really helpful for beginners like me. I have a few questions regarding some of your posts and I will try to deal with them in order, so bear with me!

Based on the amount of disasters I have had thus far, I'm going to assume (without being too pessimistic) that it is unlikely I will find bending very easy. Anything that might help me with accuracy is good, so I will build a mould.

While I'm at it, I'll probably make another solera as well, I never much liked the look of the one I made. And a radius dish.

I hope you don't mind but I'm going to copy your solera/mould. I like the idea of being able to see the joint where the ribs meet the heel from the neck (outside) side, if that makes any sense..
Now for some silly questions:
Is there any reason this set up would not work with the Courtnall-style solera geometry? I can't think of any and it just seems to make more sense to me than the Bogdanivich solera.
Also, do you attach the 'mould part' to the solera after you have joined the neck to the top? ie, is there a rebate at the bottom (soundboard side) of the mould? Or do you you cut the soundboard exactly to size before joining the ribs?
Thanks
Will

Will,

My answers will be colored by the fact that I build Romanillos style, with the sides wrapped around a top that has already been trimmed to 2mm narrower than the final body, in order to accommodate the top's ramp downwards from the bridge to the tail. So, my solera is indeed similar to Bogdanovich's, but the ramp is trimmed so that it's edges end 2mm inside of the mold. This way, you get to register untapered sides against the flat main portion of the solera, rather than having to fit them to the ramped top the way Bogdanovich does.

When building this way, my top and neck assembly just drops into the mold, and then I have to work the bent sides down in between the mold and the edges of the top until they register against the flat backing of the solera. This usually requires a little fiddly work, trimming the top in areas where it didn't get quite narrowed enough. (edit: D'uh, I guess I don't do that at all. I place the sides in first, so that the 'top' edge is caught between mold and the ramp and registered flat around the guitar's perimeter, and then the top can be dropped down inside of the sides. D'uh. What was I thinking?)

There is certainly no reason you can't bolt the mold sides to a regular scooped-out solera. The perimeter of the guitar is still usually a flat surface in this case. I will probably eventually build side models for the other soleras I already have.

If you stick with a scooped-out solera for the doming, you could certainly rebate the inside bottom edge of the side molds to accommodate over-hang of the top.

Here's another picture of the form where you can see the ramp (rather than a scoop for doming), and the form side by side with a Courtnall-style solera with a Reyes flamenco in progress (this would be about 4 years ago.)

Jim

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Jim Kirby
kirby@udel.edu