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When you do revisit your original design, the bracing needs quite a bit of work.
The X is way too far south, and there are other problems as well.

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Thanks for the affirmation guys. Here is a shot of the new design direction body style:


I'm sure I'll need a bit of direction on this one too Roger. Is this "X" correct? I sent it a bit north but it still
seems a little squat. The lower bout is Lower bout is 15", waist is 9", and upper bout is 11.25". The total
length is 18.25 with 7" of top below the scale length bridge end.

As soon as I settle on the shape I like I'll pick the 1/2 which I think is smother more flowing and
mirror/ light table the other side.

Here's the top and sides:


I think they look great together. The back is severely cupping at the moment. I'm not sure if it's
the low humidity as I don't have a system to control that yet. My plan was to build a box that would
store the wood at proper temp and humidity while not being worked, and not really get into
assembly till spring when it's nice and normal outside. I have put the back into a box with a
few cups of water and covered it:


Here you can see the cupping. I hope this slows it down. The small separation is in the waist area.
I left them in the garage one night with the cellophane on, one night stickered next to a pan of water,
and this is the result. it was upper 30's no frost outside, probably 50's in the garage. hmmmmmmm
How much cupping is considered not usable? One side of the back is cupped perfect for my
radius and the other is opposite Oh well, thanks for all the help guys.

jeremy

Someone correct me if I'm wrong, but I don't think cupping is really an issue. Once they are glued to the sides, they will stay in place. If you do want to get them flat beforehand, it's not so much the humidity level, but uneven humidity on each side of the board. If you put the boards on a flat surface (with the sides touching, not the centre) and weight it, the top will dry out quicker than the bottom and they should level out or start cupping the other way. Just keep turning them until they have acclimatized to your shop.

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Just sticker them once you have them joined, and put a bit of weight on them. They'll dry out evenly then, and you'll be right. I haven't worried too much about cupping, as the idea is to force otherwise flat bits of timber into the shapes WE want them to assume. I do make sure they're dry, tho....

Thanks for the help guys. I'll see if they acclimate in the next few days.
I've been working on a neck design. I got a nice piece of wenge I'd like
to use. I know it's a bit heavier than the standard mog, but it's also a bit
stiffer. I was going to do a wenge/ sitka/ wenge lam job, but I think I'm
throwing that idea out.


Zeke, I'm not to worried about the strength of sitka as a neck wood. Here's a
shot of my electric with a maple/sitka/maple lam. The black strips are c/f:

It's a good thing that I used a double action truss rod with this! I filed the frets as level as
I could expecting the strings to pull in some relief. No such luck. I've got that truss rod
cranked hard backwards to get any relief at all, and I'm worried it's going to blow out the back of
the neck, so maybe the soft sitka was a bad idea after all. But it's definitely stable
and strong enough in this configuration.
The other problem with the sitka was staining from the satine (red tone block) and c/f stingers
during shaping and sanding. It turned into a game of one step forward two steps back. I'd like
to avoid that on this build as well.
I'm currently considering a multi wenge lam, with the second and forth pieces of the five will
be chambered to save weight. I know I wanted to get away from inovation on this build, but I'm
afraid of a neck heavy instrument. Anyone have experience with the "D" rod?
Should I just buckle and purchase mog?

jeremy

I'm certainly no expert on bracing, since I've only done 6 or 8 acoustics, but that looks like it's in the ballpark.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon