My friend Patrick is building a Roubo-style workbench.. He and I saw-milled out six large Southern Yellow Pine timbers for the bench top a few months ago and they have been air drying in his shop since. On Friday we jointed and thicknessed them all and then did the massive glue-up. The joints came together perfectly, and although we clamped them up on a less than ideal surface (sawhorses), the slab came out about as flat as we could have hoped. We let it all sit in clamps for about 24 hours and then trimmed the ends square.
The pictures below show some of the process...The last picture is the 24"x8' slab loaded up in Patrick's truck headed home for some cleanup and mortises for the legs.
As I have said before, I thoroughly enjoy it when folks come over and we work on a project together. It's some of the best time spent in the shop for me.