Not everything goes to plan the first attempt. Any decent woodworker has internalized that fact. Take, for example, a jointing sled I recently made for my thickness planer. It’s a jig consisting of a tried and trued 2x4x96 with four boards glued and screwed at 90 degrees to the jointed edge. And it worked okay, I guess, on the first try.
See, here’s the thing: I consider myself to be a hand tool woodworker. But after truing one face and squaring one edge of a board, bringing the other face and edge into parallel by hand starts to feel an awful lot like actual work. That’s where a thickness planer comes in.
But for a very twisted board, even squaring that one edge to a trued face can be more of effort than I’m willing to expend. And that’s where this jointing sled comes in. I can clamp the trued face to the uprights with F-Clamps and send it through the thickness planer to square the edge. A quick hand planing will address any errors and then back to the thickness planer for S4S. Just as if I had done the donkey work of hand squaring that first edge.
But my prototype sled didn’t work perfectly. Just clamping to the 90 degree uprights didn’t support the board enough. Compression from the planer’s rollers bowed the wood and planed a big hump along the length. I tried using brass bar stock to support the beam but they kept falling out or shifting because of vibration.
In the end, I added adhesive-backed sandpaper to the uprights and used hot glue to shim under the length of the beam. Just like a normal planing sled. This made the whole thing quite a bit more rigid and minimized the hump, even if it did add a bit of prep time.
But it was still less pretp time than hand-planing that edge square.