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Hi,

I am out of kerfed linings, and I have easy access to something people here call "fuma". It is a 3-layer plywood with a thin veneer core and thicker outer layers. It is very bendable because the grain direction of the outer layers is perpendicular to the direction of bending, if that makes sense...



It is cheap and tempting to use, but the glue joints against the top and back would be mostly end grain, so that's what scares me. Whaddaya think?

Thanks,
Sondre

Scares me too, the end grain.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

It might be okay, then again, it might not. I'd take the time you would spend worrying and spend it on bending up some thin wood to laminate your linings. It really won't take that much more time to use one of the varous alternatives that won't have you second guessing yourself for the life of the guitar.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

It's not strictly end grain.

I've used this stuff to make bowfront cabinets and the like. It stiffens up when it's glued to a frame and laminated. I can't speak to using it for a guitar but I've never had a glue joint fail with this stuff. Of course I can't say I've relied so much on gluing just to the end grain, but even still it's not like wood as much as a softwood sponge. I really don't think it would act like normal end grain wood would.

Pretty easy to make up a few tests, break them apart and see if there is wood failure or glue failure.

One thing that might be a problem with the tests (but unlikely with the real thing) is using too much clamping pressure too quickly. The only glue joint failure I ever remember having was a scarf joint that was starved from clamping too fast. There was plenty of glue but I clamped it before it could soak in to end grain. It continued to soak up glue after it was clamped and starved the joint. Fortunately it came apart right away, long before it ever made it to a finished guitar.

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http://www.chassonguitars.com

Around here they call it bending ply. I've built a few cases using it. I never had a problem with end grain gluing. It doesn't look particularly nice but would probably work O.K. for linings. When it is bent the wood on the outside of the curve seems to crack into smaller segments.
Personally, I would use solid linings before using this material on anything but the cheapest of instruments. I think they would look nicer and have better buyer acceptance.

Thanks to everyone for the input and good advice.

For the record, I am building the guitar in question for myself.

I will get some of the stuff and do some test gluing to see how it behaves.

Cheers,
Sondre

Dang!
Maybe you could use it for sides?
What kind of wood is it made of?

I wouldn't think you could do this, that stuff is super soft. Maybe if you put plastic laminate on the outside you could but you'd probably have to laminate the inside as well. I wouldn't think this stuff would be very reflective as it is. I've used it to make radiused cabinets and doors before but it doesn't really become structural until you laminate the outside and/or glue it to a support frame.

We call it wiggle wood or bendy board.