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I pulled this ultra-super-amazingly nice mastergrade $$$ German spruce top from my stash, and besides being stiff as a wall, bell sounding and riddled with silk - OK I think I got you guys drooling already, I noticed it is very thick, one half is 7mm and the other 8mm, which is about 0.3 inch.

I was wondering if I would have any chance finding a high tech saw that could splice these in 2 for a fee, perhaps worth asking at some furniture factory?

Or how about making a sort jig using a big Japanese saw. I think I saw some that were longer enough than the 22cm of a top half. They cut extremely fast and the kerf is less than 1mm.

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Build log

Are the surfaces finished or rough? If they're rough, clean them up, re-measure, then re-aks yourself if you think it's possible.

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

Yes I smoothed both sides to perfection , still more than 7mm thick all over.

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Build log

I don't know, Alex. It sure isn't much room for error. You might end up with two 2.5mm pieces if you are lucky, but I believe you would have to be really lucky.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Don't do it. If you're shooting for a 3mm top, you've got .5 to work with including the kerf.
In my (25+years) of experience trying to run thin stock on edge through a bandsaw never works. It vibrates, etc and you'll lose all of it.
Plus, I'd get it down to thickness before I passed judgement on it's tone and stiffness. Things happen between 7 & 3 mm.
Just my opinion(s)
-C

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Freeborn Guitars
and home of BeauGuard©

I already worked a top from the same billet and it ended up at 2mm. Say I shoot for 2 tops each of 2.5, I am left with 2mm+ of kerf meat. Sounds like it is enough ?
I'm not really into making 150$, but more like into avoiding waste. It's really nice wood.

So here is the plan:

-Get a big Kataba =backless Japanese saw. 270mm long blade.
-Trim the spruce width to the min, which is 185mm for a classical.
-make the jig: MDF board, glue two rails say of 2.7 mm thickness, 185mm distance

It might help if someone else would press the end of the blade flat on the rail, while I press on my end.

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Build log

Sounds like you're determined to give it a go.
IMO the waste (already) occurred when they cut them as they are now. The bigger waste would be to have the re-saw fail and you lose it all.
Again, my opinion only. Let us know how it works out.
-C

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Freeborn Guitars
and home of BeauGuard©

I tink eet eez de debil temptin you, dat is bot I tink.

Debil-beware my friend...

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Here is what a Parlor Guitar is for!
http://www.youtube.com/watch?v=oEa8PkjO6_I

Alex, I am with Charles on this one. You are setting up for a very low success rate. I once tried to get "that extra set" out of some wood for a customer and the result was not impressive.....If you are determined you have a couple of options. I recently saw a Laguna 16"HD at a guitar makers shop and it had their 1.25 inch very thin kerf carbide band on it, with that saw I would be tempted to try it. Actually, that is really your only option in my books. Cutting by hand with a ryobi or other japanese saw in my experience is not very effective. No matter what you do, try it on another piece of lower grade spruce, trying on another species of wood won't tell you how well it will work with spruce.

Good luck and let us know what you did if you find a successful way to do this.

Shane

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Canada

It's doable...but I wouldn't try it without some really sweet gear and an ideal setup. You will need to attach the piece of spruce to a backer board to stop it from warping mid-cut and ruining everything, and then you'll need to release it from that afterward. And, in the middle, you'll need to make a really clean cut with a thin kerf blade on a perfectly set-up saw.

I've done cuts like that, but the cost of setting up the cut isn't worth it on anything but Brazilian. It's about two hours of setup plus cutting time for one cut.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

Math and statistics of success are against you. If the force is strong in the operator, perhaps, but that's a heck of a cut. Getting a .100" out of that on both sides after sanding wow, those odds are greatly against in my opinion. Now my dad could have pulled it off in his tool and die workshop, but typical high end woodworking...I don't know.

What about those wide blade veneering saws?

Ask a veneer specialist. Maybe someone at SawmillCreek can help you.

Hey! We can send a man to the moon..

Mike

Well, you guys have been far from encouraging but unfortunately I tend to be stubborn. I might be buying one of those saws soon. I was shopping for a more conveniently sized one anyway, but the long one is OK too. If I get it I'll build the "jig" and run a few tests cuts in packing grade spruce. If it won't work I'll still post here, say sorry for wasting your time with a stupid ideea etc etc

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Build log

De debil ees strong wid dis one....

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Here is what a Parlor Guitar is for!
http://www.youtube.com/watch?v=oEa8PkjO6_I

Check out Dave. http://www.borsonresaw.com/

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Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

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Alex, I tried this once, I lost two tops but they were wrc. If the board is roughly 210 mm X 480, you resaw with your blade across the 210 dimension then you have to keep the kerf from deviating less than .3 degree while sawing along the entire 480 dimension to maintain less than 1mm changes in thickness (if I calculated it right). Maybe with a special made jig that will hold the blade very straight over the entire dimension.

Also you still have to joint the top halves, unless you get them perfectly lined up you likely will loose about 1/2 mm.

Good luck, if you succeed tell us how you did it because I have a lot of honduran rosewood that I end up with a thick third unmatched piece each time I resaw it.

Tony, that is maybe a bit harsh. I already mentioned it's for classical guitar. For the small width and bracing style I use, thinning heavy and stiff tops down tot 2 mm is nothing unusual. And precisely because I wouldn't want to ruin 300y old spruce I posted this thread, to get advice. With all the negatives, it's turning unlikely I will try it even on packing grade material.

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Build log

Hmm Alexandru,

Me tink dat meybe Frei hee eez onto someting. I look at u avata and me see dat that debil, him already has been putting dat ebill saw in to your hand ready to do hees wok no?

Cheese

Keeem

I have a laguna 24 with a 300.oo blade on it I've cut thou. of tops and back and sides I WOULDNT do it Joe

Don't do it !

Maybee if eet don work out, you can make de double top...

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Here is what a Parlor Guitar is for!
http://www.youtube.com/watch?v=oEa8PkjO6_I

Why does that guy remind me of some eccentric person I have seen on tv?

However, got to admit he appears to have it down. Send the wood to him. It only costs you shipping and if he cannot do it, then no harm done.

I book marked that page.

Mike

Alex my friend I have one set of BRW that is .300 thick and I have been temped, very tempted, to consider the possibility of resawing it for the same reasons that you are tempted to resaw your German top. Other OLFers have even suggested that I do so too.

But with my need to join plates at about .140 - .150 and having had a father that used to tell me that it is better to do one thing well than to do two things (insert colorful word here.....) I plan on keeping this set as one set.....

But I understand the temptation fully.

Have you studied Mr Borson's site? Spoke with him? I have. He is a very nice guy. And smart too. I intend to build a resaw setup based on his ideas (and Iturra's too). But I doubt even if I had it, I would try this myself. I just think David has an awsome setup that anyone wanting to do any resawing should have (albiet on a smaller scale for me). Me personally, I would send the pice to David and ask his advice. He glues the billet to a stiff block. Obviously that means some loss there. But it appears absolutely essential. It is the stability of the billet that matters most.

Mike