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I have three loosely related questions about thickness of wood used for back and sides.
Please feel free to answer any or all of them! I'd appreciate it.

First, I have recently bought a nice piece of Honduran Mahogany from the local hardwood supplier. I needed some end block material, and bought the whole damned thing, it's a really nice piece, almost quartered and with nice ribbon figure. It's about 6.5 ft long, 1.125" thick, and 9.5" wide.
Question is, for a skilled resawyer (sp? haha) would it be reasonable to get 3 sets out of a 1.125" board? I figure if you saw it in thirds, you'd take off two saw kerf, say 0.125" tops. You then have three planks at 0.333" and saw those in half losing, say, 50 thou to kerf. So you end up with plates at .140" sounds reasonable. It'd suck to only get 2 sets out of a board over 1" thick.

Second, anyone know about any good resawing services in the California area? I would not mind shipping it somewhere if someone knows a pro.

Third, I recently bought a set of cocobolo from a renowned wood supplier. When I received it, I was a bit dismayed to find one half of the back badly cupped (.5 inches up in the middle, I'll give it some TCL), but worse, it was almost down to .095" at the outer edge.
Now, I'm OK, with this as a finished dimension for a back, the set is sanded smooth. what I 'm worried about is joining the plates. The edge to be glued is about 0.115-0.120" That dos not leave me much room for error. What's the lower limit that you guys would consider joining plates?


Seems that if I took the thin side and clamped it down, ensuring the gluing edge is flat against the work surface, then applied glue, join and applied downward pressure right at the joint that it would require minimal leveling....
I'm using a center strip, perhaps I could glue that strip to the thin side, taking great care to get the seam level, then glue the other plate to the thicker center strip(a zig zag martin type strip....thinking about it, that sounds doable.

I'm sure the seller will take it back, but it's a hassle, and I really like the set...

Thanks for your help, as always!!
Mike

You might talk to Borson resaw in Fort Bragg, CA
http://www.borsonresaw.com/

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Jim Watts
http://jameswattsguitars.com

Joining plates at the thickness you stated is easily doable. Just make sure the wood is flat against the table once you push them together.


Posted using two tin cans and some string.

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PMoMC

With a well tuned bandsaw & blade, I think it's reasonable to get 6 slices out of a 1-1/8" board.

With patience, I think the Coco will flatten out. Put it on a shelf with a few boards on it. Check on it in a month, add more boards, repeat.

Kevin Looker

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I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

Just did the math. With a Woodmaster CT and 0.048" kerf, you'll get 6 slices 0.1475" thick. This doesn't give much or any room for error. IMO, Mahogany is a fairly easy wood to resaw (comaperd to Cocobolo) so I don't think this is unreasonable.

Kevin Looker

_________________
I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

I agree with Kevin, 6 slices is doable but there is very little room for error. Your wood needs to be pretty dead flat after every cut and your saw set up well.

It sounds like your cocobolo has some case hardening, which can be common for super dense woods. If it was the outer slice from the original board I'd bet on it. There's not much you can do unfortunately... flatten it under weight, let it dry to 8% if it's not there already, and hope for the best. In the end you may be able to thin it enough to easily straighten it out with bracing.

Thanks for all the info, guys.

I think I might give Borson Resaw a try. His saw looks pretty serious, and with a name like Borson Resaw, I bet he can resaw! The Hog board is nice, flat, thick, etc. Should be good.

The cocobolo...Sounds like I'll be OK. What's interesting is that one slice is warped to all hell, and the second (a bit thicker) is almost dead straight. Sounds like case hardening. Does this equalize after enough time? I do notice that when I get woods that are cupped, if I start to thin them with a plane, they usually seel to go limp and lay flat.

I have other cupped wood, just none this thin, that's what freaks me out.

cheers!

Way back when, in the days when I was selling thin resawn hardwood on Ebay, if the board was cupped I simply wetted it on the concave side until it approached flatness and then resawed it.

Worked every time.

Yup!

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resawing can be hit or miss. the best woodslicer blade does not always yield optimal results. I always leave plenty or room for error. anything can happen. I have had flat boards bow up as soon as i take a slice off. obviously, they weren't qtr sawn. however the possiblitiy is always lurking in the shadows. One tip i recently came across that has worked great is using a small blade. like 3/8 instead of 1/2 or 5/8. the reason being that the blade has to be tightened less there by putting less strain on your motor. That means more power for cutting. I have a 1 hp grizzly and so far this has worked great for me. i suspect that if try something super dense like jatoba i might be in trouble. osage orange, bocote and rosewoods have been no prob. just a suggestion. On the cocobungholio be sure and mark the thin portion with tape or something so you dont forget where it is. i agree that .095" isnt too thin but if it were me i would have a beer or two and forget that little detail when joining the plates. just saying....

T