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Ok, so everything I've built to this point has been in the electric side of things, and I just got started on my first acoustic. The back and sides are plain mahogany, the best billet I could find among 4 huge pallets of mahogany ( I love the guys at my local timber place, they let me pick through everything )

Anyway, the only thing I've bent before is bindings, but it was great fun and didn't take me to long. They sat in the mold for a few hours, then I took em out and tweaked em a bit more. This morning, however, they are not quite flush to the mold. I'm wondering, what is everyone's accepted margin of error here?

I think you want the sides as close to form as you can have them when you glue in the neck and tail blocks , mine looked sort of like yours do now when I began ,so what I did was clamp all the gaps tight to the form like you did with your f -clamp at the rounds of the bouts, then when I glued in my blocks I removed all but the waist clamp ( after the glue dried of course ) and it stayed nicely in shape and ready for lining ... Jody

You need Lower bout , Upper bout and waist spreaders that hold the sides flush to the mold. The amount of inconsistency is fine the spreaders will take care of this. Once the end blocks and linings are glued up the sides will move very little. I leave the spreaders in till the back is on the n the sides will not move at all.

I think alot depends upon how accurate your mold is too!! Jody

That looks acceptable to me! I would just clamp or spread all the way around when gluing in the blocks. Once the blocks are in, and if there are a few gaps, it is ok if both sides have the gap in the same area. Like Michael said, the spreaders should take care this until the back is glued on. As for the gap at the butt end of the guitar, no biggie, your end graft will cover that up. Looking good!

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Tracy
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Brady, I think you will do just fine with these sides. The above advice will get you through this build.

For the next box I would leave each side about an 1/8" 'longer' than your center line. This will 'push' the sides out to the edge of the mold and shouldn't leave any gaps the whole way around. John Hall shared this great tidbit with me awhile back when I questioned why his molds do not have a spreader in the lower bout region. Every box has come out looking great and holding shape since then.

Good Luck!

Brady nice job on the side bending and wood selection.

I agree that you will be fine when you make a set of spreaders and let the spreaders take out the gaps evenly.

I use spreaders and I screw through the mold into the tail block and the neck block.

Yes, I see that bout spreaders are needed. Thanks for the length tip, Andrew, that's a great trick, I'll try it on the next one.

Very clean mold, Hesh. Nice touch using the threaded spacers for the spreaders too

Going to go make some bout spreaders now...

Brady just one more thing if I may please and not that this is something that you would do but it has been done before here on the OLF.

Make sure that your spreaders, what ever sizes and shapes that you make, will fit through any possible sound hole size that you might use...........

LoL........Sounds like you may have put you foot down that hole once

I never did it Michael but perhaps this was how resonators were invented.......