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Discussion Starter · #1 ·
Hello everyone! I have been researching how plywood and veneer is made. It's amazing to see a log "unrolled" into a sheet of wood but I've been wondering how thick can wood be cut using this method? Could a log be unrolled into a sheet that is half an inch thick? Or better yet, would a sawmill take a special order to cut wood in this fashion? I ask because I am researching a project that would require me to have complete control over grain orientation. Unrolling a log is the only method I've found so far that gives me this control. Thanks so much for your input, RockerBug17
 

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softwoods are regularly rotary sliced to 1/4" for use in making plywood, but I think 1/8" is more usual and I've never heard of anything thicker than 1/4". I think 1/2" would be pushing it for any wood (but MAYBE it could work for really soft wood although it seems unlikely to me) and even 1/4" wouldn't work for hard wood.

Rotary slicing is actually the WORST way to do thick slices since it combines the largest curvature of any slicing method along with a grain orientation that is most likely to split in that direction.

The kind of slicing where the cut is close to a tangential cut would be the one that could produce the thickest slices, but then you would be limited in width.
 

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Discussion Starter · #4 ·
My finished products would be anywhere from 12mm to 4mm thick, after sanding, lathing and calculating in error. Both those measurements would be at the utmost ends of my spectrum. I expect 8 to 6mm to be more typical though. Could a maple log be temporarily softened to achieve a rotary cut thickness of 8mm?
 

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My finished products would be anywhere from 12mm to 4mm thick, after sanding, lathing and calculating in error. Both those measurements would be at the utmost ends of my spectrum. I expect 8 to 6mm to be more typical though. Could a maple log be temporarily softened to achieve a rotary cut thickness of 8mm?

The log can be cut into lumber which can be resawn to any thickness you need.






 

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Discussion Starter · #6 ·
The log can be cut into lumber which can be resawn to any thickness you need.






Would I still be able to control the grain orientation (angle relative to cut)? To be more specific, I am trying to construct drum shells that resonate at specific frequencies. In order to do that I need to stress the grain in different amounts when bending it into shape. This is all so the wood will add it's characteristics to the sound of the drum. I could use a stave method to construct the drums. The only problem is the limitation to tune the drum to a specific frequency. Increasing the mass of the drum changes the frequency but decrease the resonance. I've also looked at steam bending but again there are limitations. My ideal scenario would be to have a single flat piece of wood that measures 8x10 ft. I could then adjust the angle of my cut in relation to the grain to achieve the desired stress while keeping the drum shell thin enough to resonate.
 

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Discussion Starter · #8 ·
That could be achieved by how the log was cut. Go to the link in post #2 and you can see the different cut methods.
I'm not sure if I understand the other veneer cuts. They all seem to have the grain running the same general direction.

These videos may help explain what I am trying to do. The only difference is I am trying to apply that method to thicker sheets of wood so that I can steam bend them into shape. If I were to make a 22 inch diameter by 18 deep bass drum I would need approx. a 70 inch sheet 18 inches wide. A compromise would be to use seven 10 inch pieces, steam them, and then glue them together.

Looking at the different veneer methods it seems I would need a massive tree to get the cuts I'm looking for with a minimal amount of pieces. Now, I may be spatially impaired at seeing the other veneer cuts working, but it does seem easier to take long and wide rotary cut veneer sheet and cut it from corner to corner to get the angle I want.
 

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Rotary cut would be the way to get a sheet of solid wood veneer that large. It's unlikely that you could buy it or order it that way and that thick because it would crack apart. Production veneers are usually machined in 1/40", 1/32", and 1/16". In large sizes rotary cut, are utilized to be a facing on a thicker substrate, as in hardwood faced plywood.

I don't know squat about the species of wood for drums or the grain direction. But, there are ways to get a wood faced substrate to bend. You can buy a plywood that is made to bend, called "bending ply", or "wiggle wood", and easily bend it on curves. It comes in a variety of thicknesses from 1/8" on up. Once that is formed, it can be veneered with the veneer of your choice.

Or, you can take any plywood and kerf the backside with sawcuts. That method consists of cutting parallel grooves across the sheet, evenly spaced. How close together and the depth of the grooves will determine the curving ability of the plywood for it's thickness. Once formed, if it has a hardwood face to start with you're done. If not it then can be veneered.

Or, if you are handy in the shop, you can cooper solid wood to form a curve, like in wine barrels.






 
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