Official Luthiers Forum!

Just wondered if anyone has a preference for either kerfed or solid linings on steel string guitars for more reasons that ease of installing. I have bought a load of solid linings simply because they are cheaper and allows me to practice using the bending iron. I have heard some say they make the body more rigid, but what does this do in terms of tone (if anything at all)?

Well, it all depends on what fundamental dynamics theories you hold too...

I am sure Al Carruth could add some insight, but to get it kicked off...

1. I have never had any luck with bending solid linings. cracks cracks cracks - even after soaking them in the bath tub. I move to 0.04" laminate solid linings that I bend and glue for each guitar. If you figure out a good process, let me know.

2. Fundamentally, when we string up a guitar, we are looking for a dynamic response from the top - the excited surface. Hence it is braced specifically to respond a certain way that is pleasurable to the ear across its spectrum. If your entire guitar was soft, and was able to deflect so much to absorb all the energy imparted to by th strings, you could conceivably achieve the point where the only response energy would be at frequencies sub our hearable spectrum. The more rigid the sides (and back) the more energy is dissipated through the top of the guitar - what we as luthiers fundamentally voice to sound pleasant - that is where we exert our control. Weaker sides can deflect more, effectively " stealing" energy that one would rather have dissipated through the top - and as of yet, I have not come across too many people voicing their sides specifically because everything beginning with the geometry is really not right for a frequency response from 50 Hz - 15 kHz.

Beyond that - some people like their back to move a little - some people do not. A good analogy to think of would be about everything percussive - from congas to drums...Very heavy sides that are stiff and offer no excitation because of their high mass and stiffness values, so all the sound is dissipated through the top and sometimes bottoms of the drum.

That might help a little.
Stephen

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www.ziegenfussguitars.com

Generally speaking, kerfed liners can be wider than 1-piece solid ones. I can bend willow at 5mm thick, but that's about it. Sometimes it's nice to have more gluing surface; for example, if you're using a lot of purfling lines or something else fancy on the top.

Solid liners do stiffen up the edge a lot before you glue on the plate. I don't think they make a lot of difference afterward. It's my feeling that the 'Olde Boys' in Spain used them on the back so that the back edge would be stiff enough to shape off easily with the body top down on the solera. you can get nearly the same effect by using reverse kerfed liners.

Alan Carruth / Luthier

I agree with Al, I don't think the type of lining matters much, if at all, once the plates are glued on. The way I see it, for kerfed linings to make a more flexible box than one with solid (or reverse) linings, the wood between the kerfs would have to deform. Anyways, I haven't heard of anyone actually testing this (destructive testing? crash test dummy guitars?), just a lot of opinions.

I've also used willow for solid linings for guitars and mandolins, and 5 mm sounds about right. One more reason for using solid linings for the back and not the top could be that some feel solid linings look neater...

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Rian Gitar og Mandolin