More important, what would you use a massive beam like this that would require jointing?
I could see resawing it, but edge jointing? Must be one heck of a big project.
I needed 12/4 stock and one of my local suppliers located a distributor out of state, that had three that size that were supposed to be S2S. I thought I could get away with just two, but since they were the same stock and their yield would all look very similar, I thought...why not. I can always use Mahogany.
As for cutting to size first, that would have been a start, but I did not have a good edge to start with. This lumber was for one of the Mahogany bars I have posted in the past. It was also for some dining room cabinetry and crown moulding to include a tray ceiling.
I needed to first rip some long lengths to resaw for crown and other moulding.
Don't know of any planers that could handle 20" plus an 18' long sled. Cabinetman was asking about edge jointing.
If it could be crosscut into more manageable pieces it would be easier. I'd still use winding sticks, straightedges and handplanes. The 20" width would be the biggest pain for me, as the top edge will be up a lot higher than I would prefer. My left face vice on my bench doesn't have a lot of depth. The right leg vice wouldn't be too bad. I'd probably remove the left vice and make some supports and clamp the board to the leg.
Nothing that long, I've got a 48" metal one that is accurate enough for wood. If I was working with wood that big I'd probably have at least a 6' level.
If I had to joint the full 18' length I'd probably set up a laser parallel to the top and do spot measurements as I move along the board.
Another thought, If the edge was really rough I'd probably snap a chalk line and plane to it. If there was a lot of material to remove I'd remove a bunch with a circular saw and a sawboard.
Just read what I wrote and laughed. Auto correct really screwed me up there.
Also I guess I misread your question and didn't see the edge part. For some reason I thought you wanted to face joint. I've only edge jointed some that thick and long one time and I used my Festool track saw to do it. But my piece was only a little under 8 feet. I suppose you could put several rails together if you had access to them. Or perhaps make your own long rail by putting together several pieces of ply.
Short of that maybe you could mount the stock on top of a really long straight edge (multiple pieces of ply? ) and run it through a tablesaw?
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