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ByHaving had some problems on 1st, I wanted to start a little thicker. Can't do it because I just measured the next set and it's already down to .08". I'll have make sure I do a better job of fitting them in the mold this time and avoid any buckling while bending.

I also want to try cutting the sides to the plan shape before I bend them. I want to avoid driving the bus altogether. I think I'll make solid linings and bend them on the iron. Probably a double layer of 3/16" for the linings for ease of bending.

These are my thoughts right now. What do you think?

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Hutch

Get the heck off the couch and go build a guitar!!!!

Moving along with pipe bending and just trying to do a better job. This piece fits way better than my last build and I'm letting it cool in the mold before I bend the second side. I pre-shaped them this timeme.

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Hutch

Get the heck off the couch and go build a guitar!!!!

Just a helpful hint, center your mold to your sides.

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I thought should do that. Thanks, I'll do that before I start the second side.

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Hutch

Get the heck off the couch and go build a guitar!!!!

.08 is where I bend rosewood…

This is so much better. I checked the sides for square and they're perfect.

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Hutch

Get the heck off the couch and go build a guitar!!!!

I believe this how I got them from Martin. Still had some writing on them and they are .08. I didn't even bother with the strap on the outside. They bent so easy.

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Hutch

Get the heck off the couch and go build a guitar!!!!

.08 to .085 for me on rosewood, .07 and thinner in a cutaway area. Don mentioned about centering in the mold. Yes, but approximately.
Keeping the top section equidistant from the mold is also something I do, I'm sure others do it as well.
As the top is relatively flat it keeps the sides square to the mold for doing the head and tail blocks later. I just place
a strip of wood under each end of the mold and press the sides down until they make contact with the bench.
Just one of those seemingly unimportant tasks that makes the whole contouring the sides outcome wind up where
you want it. For me the sides stay in the mold like this until the plates are glued on.

The main thing with pipe bending is to get the wood fully heated before applying significant pressure. Once ripples get started, only the peaks make direct contact with the pipe, so they heat up faster. If you apply pressure before the wood inbetween is up to bending temperature, only the ripple peaks will actually bend, increasing the ripple amplitude and creating stress in the wood as some of it is still trying to spring back straight.

Boy, you guys bend guitars with thick wood!

Even cellos are only 1.3-1.8 mm. Violins 1-1.3mm or so. I bent my guitars at about 1.2-1.6mm. 2 mm on the linings.

It worked.

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Why be normal?

Re: centering the mold:

What is meant by that for already-profiled (i.e., tapered from neck block to tail block) & bent sides is that the mold should be uniformly set in from the top edge to keep mold and sides square to each other.

For those working with the outside mold/radius dish method of construction, centering the mold so that the amount of side showing at the waist is about even works, provided there is enough clearance between mold and radius dish to work final profiling and flushing up the linings and blocks.

If the sides are as yet unprofiled, centering the mold on the sides works fine, and gives good support for installing and clamping the neck and tail block.

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A constellation only takes shape when one maps the whole.
- Beth Brower

"If the sides are as yet unprofiled, centering the mold on the sides works fine, and gives good support for installing and clamping the neck and tail block."
This is true.... but if not in the habit of placing the mold uniformly from the top from the git go and always, the next time you'll think to do it will be after you remove the box from the mold with the plates glued and you're staring at the out of square end or ends.
Making it a rule to do this keeps me out of trouble when I forget to think.

I always profile my sides before bending and cut to maybe 1/2 -3/4" over length at each end.

I have the waist position marked on the side template but I always double check by putting a long piece of tape on the half template for the body shape and marking the ends and the waist. The tape can be placed on the side to confirm your marks for each end and the waist.

Only downside to profiling before bending that I can see is that there is the possibility that if you have a brain fart you can bend two right or left sides. I got to where I position my bender so the top of the side is always facing me. After I bend a side I turn the bender around and reclamp it to the bench.

You still have to drive the bus a little for fine tuning but not that much.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

I did the tape thing as well. It's odd that the center of the waist isn't included in the plan profile, it is now I was very careful about making the 2 sides opposite of each other. No bus driving on this one. I really can't afford the correct ones and I don't want to make them. I just want to make guitars. I think I can manage it all with a curved boar and planes. That's what I'm going for on this one. Someday, I'll take the time to make some but for now, I'll do it by hand and who knows, maybe it'll work out for me and I can avoid those nasty things forever.

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Hutch

Get the heck off the couch and go build a guitar!!!!

I made some side profile templates from lexan and have the waist marked on them. I usually bend at 0.080 but finish about 0.065, depending on the individual piece.

Brent