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Im curious to kno if there are any books that are geared at bending wood.
Im having a problem with bending because I have a tendency to scorch the wood as Im bending it.. thanx in advance for any help that someone has for me ..
Donald

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Nothing like practice! My pleasure. Try 2mm espciacially for the cutaway, MUCH easier. Got to go practice my myxolydian mode now...
Donald,.

Tauton Press - the folks that publish "Fine Woodworking" and "Fine Homebuilding" and such - published a books which I believe was just called "Bending Wood" (I'll have to check my copy) back in the 1980s. If you're familiar with Tauton's materials they are of great quality - I don't know of any common, commercial ones better - but "pricey" so you don't see them in your grocery magazine rack but usually at bigger dedicated book stores. Anyhoo all of their books I've gotten are compendiums of articles from their magazines - FWW in this case - from previous years along with Q&A from their "experts." You might check out Amazon or a similar site and see whether you can find the book as it has been out of publications for at least 20 years - probably closer to 25. It's work the scratch but, like everyone else who's responded, I agree that there is no substitute for experience but what a book can do is help prevent the grossest of mistakes and perhaps provide specialist info for a rare situation. Oh, I assume that you realize that FWW isn't dedicated to luthiers but more for fine furniture builders but I seem to remember that the specific book did have an article on guitar side bending (classical?) and jig building (might be getting this mixed up with their book on wood finishing and the French polishing article for guitars).

Hope this helps

Rob
Thanks Rob- The way I see it is, any info is more than I had to start with so it is appreciated :-)
Peace,
Donald
I've done quite a bit of violin side bending. Wood is 1.1mm, highly curled maple and you daren't scorch it as the mark will show right through. I use an electric bending iron with a thermostat. It's handy as once I've established the setting I can leave it at that for all subsequent bending. Even so, I always try a test piece once I've got it up to working temp. Bending is done with a metal (brass, spring steel) strap ouside the wood to prevent breakout in the short grain. Between the wood and the iron, I use a damp (not wet) piece of cloth, sheet or t shirt material. It works fine on fiddles but I've also used it on guitar sides with tricky grain. Plain maple is usually a doddle to bend with the right temp. Just keep it moving against the iron to warm it overall and then try a little pressure. If it's ready to go, you'll know, but don't linger. If you watch a master like Romanillos, you'll see he rarely keeps the side in one place against the iron.
Side benders are fine, but I don't always trust the bend at the waist, so I often use the iron for the waist bend and then clamp it into my bender.
Good luck!
Hi Dave - thanks for the input It is appreciated- I am finding out that bending wood takes a bunch of patience and practice too.. Once again thanks for the info....
Peace,
Donald
Dear Donald,

Although I use a bending-iron (mine is a 40 cm stainless steel table leg, I use a soldering torch to heat it from the outside, when bending there is no more heat added) I think I have some info for you (and for Luis).

I don’t know any book geared at bending wood but I found some info on that in Irving Sloane’s “Classical guitar construction”. (First published New York: Dutton, cop. 1966, also London, Omnibus Press 1976, ISBN 0-86001-232-8)

In that book a “boiling through” is described. This is a galvanised tin through (32” long, 6” wide and 4” high) resting on a 2 burner stove. (p.30).
The use is described as (p 40/ 41) “fill trhough with 2” of water, heat until steam is rising, then put in the board(s) to be bended. Put in hold-down brackets and cover the through. An hour and a half of steeping will make the wood plastic enough to bend." (This is done on a bending form)

Of course: the book has more info than this short summary (als pictures) but since it’s not my copyright…

The book has a bibliography, but nothing jumps out as beïng about wood-bending. Maybe some more info on that in the Wood Handbook (Us Department of Agriculture , free downloadable as PDF at: http://www.fpl.fs.fed.us/products/publications/several_pubs.php?gro... (the link does work here, or you can copy/ paste in the adress-bar of your browser)
Just checked the contents, no obvious info on bending – off course- but lots and lots on wood ;-)

Anyway, best of luck with your reasearch and projects!
Bart
Bart, Sloane's book was my first exposure to classical guitar building and my first guitar was built with its guidance. However, the boiling the sides routine was not its brightest point and has its problems. The first, obviously, is that it's pretty darned cumbersome to do it,.. The second problem is much worse. The different densities in any set of sides react differently to moisture and swell differently. The net result of the process is sides with very significant ripples across the width. It can be so bad that the depth of the ripples ican be greater than the thickness of the sides. There's no way to level them without severely weakening the sides. In the end, bending on an bending iron or Fox bender is the best, and the dryer the better.

Bob
Dear Bob,

I was merely pointing out that I know of some other way to bend wood. I never suggested that it is/ was a good or safe way... (And Sloane does give warning on possibly occuring problems with that method)
I’m glad that you, with your hands-on experience on this boiling method, point to the problems it brings with it. Good to know that you have found good reason not to use it, so we all can leave it for what it is: a more time consuming, hazardous and painstaking alternative for something which can be better and far more easely done.

Why would we do our best to find good quality, long air-dried, tonewood if we are going to boil it for 1 ½ hour? Seems to me that (using that method) one could better use kiln-dried wood, since during the heating/ bending that is what one would be actually doing...

Bart
"Why would we do our best to find good quality, long air-dried, tonewood if we are going to boil it for 1 ½ hour?"

I know, it seems strange, doesn't it? In truth is that, regardless of how we bend the sides, we must brutalize it to get it to conform to the desired shape. We have to look back through our own building process, though, to discover why we would need pampered wood. Have you ever tried to thickness wood that has warped because it was unstable through lack of seasoning or change in environment? It certainly doesn't work out well in my shop. We really do need stable, well seasoned wood to even start the building process. And then we abuse it mercilessly.

Bob
Bob, you recalled to my mind my first ever guitar (mercifully long-forgotten and consigned to the fire!) I faithfully followed Mr Sloane but unwisely chose heavily flamed maple for my first attempt.The result looked more like corrugated cardboard and by the time I had scraped/sanded all the little hillocks out, I ended up with sides less than 1.5mm.
Nowadays I build laminated sides usually with maple as the inner skin; thickness both skins to 1.5mm, bend them together in a side bender then use West's epoxy to laminate, again in the side bender but with protective layers of waxed paper.The result is fairly rigid sides that don't spring back. I have a theory that the top dissipates energy into the sides; therefore aiming at a rigid set of sides should allow more energy to be put into the air chamber. Seems to work for me!
Hi Bob -- In regards to the sides of the guitar I have heard the theory that the sides of a guitar are like the sides of a drum and should be as ridged as possible in order for the top to act like the head on a drum and vibrate as much as possible. ( correction requested )
The process of bending them is the hard part for me.. I have bent some maple and it came out looking like something that was picked up in the ruins of the building in NYC after 9/1101.
( no disrespect to the tragedy )
Meanwhile I have ordered an electric bending iron from LMII along with their steel strap
to maybe get me on the rite track... I also have a line on some maple that I could practice with on my way to bending some mahogany or other wood that is good for sides.
Peace,
Donald
Yeah, well, my first one (from Sloane's book) still sits in my guitar case, a mere space filling model for a gutar. A truly humble beginning.

There are a number of builders that laminate their sides. The effect of that is a bit hard to pin down. It certainly adds some mass to the hoop that supports the top. That could have a couple of effects. One is to add some inertia that resists movement generated by the bridge so that it spends its energy moving the top rather than the whole guitar. The other is that it adds mass in general to the guitar and that acts like the flywheel of an engine, to store and release energy. The effect of the added mass is to lower the peak volume a bit but provide more sustain.

Another way some builders use to get those two effects is to make very heavy, rigid laminated top linings. Greg Byers, Miguel Rodriguez, and Antonio Marin Montero come to mind. I'm building a Marin copy right now and can let you know how that goes.

It is certainly true that the sides are interactive with the rest of the structure. My analytical recordings suggest, though, that the energy transfers could happen through interactions with the air modes rather than by mechanical linkage with the top or the back. When I take recordings of an E scale on the high E string with the microphone directed at the flat area of the side below the waist, I see peaks with highly significant amplitudes at frequencies that correlate extremely well with the rankings one would assign when you are playing the guitar and listening to it (rather than being out in the audience). These same frequencies corrrespond to the notes that are supported by the air modes that have the greatest interaction with those parts of the sides. Preliminarily, it suggests to me that those portions of the sides could actually be tuneable elements that can be modified to enhance the players' experience of the performance. But, ya know,... this could all be just the arm wavings of a demented senior builder. I need more data to pin this down and, of course, I'm in the process.

Cheers,
Bob

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