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Starting on number four, larger body style from plans for a Grand Auditorium. I had a heck of a time getting the top, back and sides thickness sanded correctly. Took two trips to the local woodsource, drove 40 mi each way, it cost over $80, was charged double their normal rate because I insisted on standing there and measuring til I was happy. Then I ended up not getting anything as thin as I wanted. Mill operator acted so confident in his measurements using some gauge I couldn't read...blah, blah. In other words, I screwed up not trusting my gauge rather than his word. Sides are about 0.106".

I bent the first one ok, thinking that with many respected folks doing laminated sides and saying it's a sound improvement, mebbe thicker than my normal would help the final sound. Like most bends I've done, there is some relaxation as I fit it into the mold, but since they are so strong, I'm not all that comfortable trying to force the sides all the way flush with the mold, thinking the guitar might end up happier long term if I just use enough pressure in my mold clamps that any gaps are equal on both sides and the side pressures won't try to deform the final box. On the other hand, I can make them fit flush with my mold clamps, just not sure that's the right call. I haven't bent the second side yet. I like to stall when I'm not sure about something and ask opinions from folks more experienced than me. I know I'm gonna have to plane the top and back a bit, but there's no rush for that.

Thanks in advance for any and all inputs. Roy

What kind of wood?

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

East Indian Rosewood. First time using it.

EIR usually bends fairly well, but if you can use a scraper, and scrape off .006 - .010 from the inside surface that might make it go easier.
The extra thickness won't be a problem if it bends O.K., it just makes it harder to bend.

Is it mainly the waist that is giving you trouble? If so, just thin it in that region as Clay said, and abandon your plans for a cutaway.

One of the times I visited Tony Ferguson the professional guitar finisher after we got done playing with his bulldozer in the yard we were in his shop and talking about bending sides. He was making acoustic guitars with sides that were .150" thick! I did not think you could bend wood that thick but he was successfully doing it.

There is a school of thought in acoustic guitar design that believes that the sides have very little to do with tone beyond the ability to isolate and... couple the back as needed for a desired outcome. The double side camp are pretty much building drums where the heads are active but the rim is inert.

Sounds like your sides are too thick to reliably bend with how you are bending them. You mentioned over .1. I bend at about .080 and had no problem conforming to the mold.

You’re getting good advice from more experienced folks than me, so take this for what it’s worth - don’t force the sides to fit the mold and build the guitar that way. Get your bends sorted so they fit the mold appropriately.

That is a bit thick sand them down or scrape. If you need to make it fit them old a little making it fit won't hurt. I have heard that this would cause undo stress and this is not true .
I bend at .075 in so you can sand or scrap .020 you should be ok, If you do bend thick find something about 4 lb so you can place this on top of the sides , as the wood get ready to bend you will see the weights sagging . This is a sign the wood is ready , take your time and it should go well. Don't let the blanket get over 350 F I would think you should get able to bend this at about 275 so watch the wood and let us know how it goes.
Also this thick you may want to keep it in the bender till it is room temp. Check the bend before removal by lifting the lower bout hold down and judge the bend. If your tight on the pattern your good if not set the blanket to full heat to 325F then set 275 for 15 min recheck

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John Hall
blues creek guitars
Authorized CF Martin Repair
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You Don't know what you don't know until you know it

Actually, the bending went very well, meaning I didn't have to fight it, just let the wood relax, and like John says in his videos, the springs did the work. I left it in the bender overnight. I have the first side in my mold, and went ahead and tightened the mold clamps in the upper bout to fit the mold. Didn't hear any cracking noises, so I was just worried that I'd have more stress coming from the sides that would cause some undefined problem in the future. I'm making new mold clamps for the lower bout, as the GA and the 000 are a good bit different there. The second side is cool in the bender now. I'll try the lower bout release and recook, pretty sure it will need it based on how the first side went. Thanks for the inputs, I believe this is going to be ok after my over-reaction. Roy

Update,,,,the second side was in the bending mold when I read John's suggestion, so ran the higher heat cycle on it and worked on new mold clamps, including one for the waist, which I had not used before. Let it sit in the machine for two days. Took it out today and clamped it up. Much better fit, took to the clamps with no drama. Need to make waist clamps for the 000's too. Think that would help in the binding process.

Now I have the first side back in the bending machine and plan to do the same to it before cutting the ends, clamping them both, and gluing on the tail block. Head block not ready yet. Thanks for all the inputs. Roy