Official Luthiers Forum!

Yes, the back strip is continuous and glued on with the back in it's dish. The ladder braces are cut out so they bridge over the back strip, and they, too, are glued in with the back in the dish. The side pillars rest on the back brace ends and over lap the side doubler which you can see there under the reverse kerfing. Now I'm also gluing a strip of 1/4" wide CF around on the inside of the kerfing, and on one guitar, I then bound the top with three layers of .021" thick CF.   That sucker is strong...

All the tension from the neck pull is being taken by the back, so that's handled by the CF topped back strip and the fact that it's highly unlikely that the back dome will flatten out with the CF topped braces.   Even if it did, since the neck can be tilted for action adjustments, there will never be a need for a neck reset.   

I think you can use a balance of CF and wood working together to carry the loads, and now that I've gotten to this point, I'm going to try backing off a bit to lighten things up. This guitar is probably way stronger than it needs to be. I'm moving toward a classical guitar project, and I want to make that guitar fairly light, but use all these ideas in it.   

Rick,

Thanks for the explanation.

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

There are a lot of very, very good marine grade mahogany plywoods for those who either don't like the birch or don't trust the Glue.  Look for the 1088 certification.  Look for it where boatbuilding supplies are sold.  Very nice stuff.

One could also cut it on the bias to the sheet edge so that there is no real end grain on the block.  No real edge grain, either, but you makes your choices...

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Expectation is the source of all misery; comparison the thief of joy.
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Rick, a query: where do you get your sheet and round bar stock from?

"The Graphite Store"...Google 'em.

Oh, for 1/8" x 3/8" or 1/2", I get stuff from our own Jim and Rebbecca Watts of Los Alamos Composites...great folks, great products, great prices.

Thanks! ..and I've got a sizeable stack of bar material from Jim and Rebecca right here, perfect service, and when I need more, I'll be getting more.

Thanks, for the pic Rick! Now to really show my amateur goofiness. It looks
like your block is only one piece (unsure from the angle whether it is 1/2 or
3/4") So I assume you do not do a mortise and tenon neck joint. do you use
a straight bolt on butt joint? Thanks, K

1/2" thick neck block and a tilting adjustable neck.   I'll post pics when I can. There's a discussion in the "buttress" thread on it all.   

thanks, K

1/2" Baltic birch would work fine for a regular bolt-on butt joint, too, as long as you had something like the flying buttresses in there.   We use the same stuff in our ukuleles, too.

I've never done a bolt on butt, the mortise and tenon bolt method seems
much more stable but I would be interested in seeing your adjustable tilt if'n
you'd be willing to show it! Thanks again!

Yeah, it seems like it would be more stable...but in reality, a straight butt joint with no mortise works just fine. Two Allen head bolts, Belleville washers in addition to flat washers, tighten that sucker up and it's fine. That's how we do the ukes, and we don't even bother with the Belleville washers.   You'd think there might be an issue...and there isn't, so I go for what's easy.   Besides which, if the bolts loosen because the neck block shrinks, then just tighten them up.   But with all the waterproof glue lines in the Baltic birch ply, the stuff is amazingly dimensionally stable...much more so than mahogany.   And thinner in this case is better.

Rick, do you think the birch ply would work for a mortise and tennon type neck joint if it was laminated as 3 or 4 pieces thick?

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“If God dwells inside us like some people say, I sure hope He likes enchiladas, because that's what He's getting”
-jack handy

I don't see why not. But...awww, never mind...

Rick can i ask what the rods are for? I have noticed these before in another pic you posted. Mike

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Guitars, guitars and more guitars.

Hope you don't mind me asking, but where do you get Baltic Birch Plywood? And is it expensive?

Andrew, Woodcraft and Rockler carry it up here. Yes, it is more expensive than the hardwood ply you can get from the Borg. How much more will depend on your neighborhood. You should be able to get prices from their online stores.

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Aoibeann