My friend Pat Hawley was commissioned to build an acoustic bass guitar. This guitar is to be nearly 20" (50 cm) wide, and he could not find any pre-cut guitar wood that was wide enough. But he had some wide mahogany shelves kicking around, so he brought those to my shop to resaw them.
Before resawing, we cut them to the actual width needed. The wider the board, the harder it is to resaw, so best cut to width first.
Here's cutting the sides.
After I cut up the really wide board for the front and back, Pat had the idea of taking some pictures and video of the process, so I figured might as well put them online. Unfortunately, there are no pictures of cutting the really wide 26 cm (10¼") board. These took up almost the entire cutting capacity of my old 18" bandsaw (with the guide moved all the way into the case).
It was slow cutting, but I ended up with some very clean cuts. I used just a 1/2" blade, about 3 TPI. That sort of blade is not designed to resaw 26 cm deep, but with a freshly sharpened blade, and cutting slowly, you can get away with a lot.
Pat, happy with his guitar parts!
As it worked out, the 21 mm thick boards yielded four layers of 4 mm each. The wood in the final guitar will probably be about 2.5 mm thick, and I figured it would be best if it wasn't too thick so Pat wouldn't have to use his thickness sander as much. It was fortunate coincidence that we managed to get four layers out of the boards!
Those boards came out pretty smooth, not obvious at a glance which surfaces were the planed outside surfaces and which ones are the milled ones.
If you enlarge the photo, you can see the saw marks (click photo to enlarge)
My 18" saw is not entirely dust proof. I had a hose to my dust collector clamped to the saw to catch airborne dust below the blade. Most of the sawdust went into the collection drawer at the bottom of the saw, but I guess a fair amount still made it out.