Got a couple of hours this weekend to haul everything up out of the basement and work on putting together the frame for the top shelf. Since this frame is so narrow along its length I was unable to clamp the back side of the assembly when attaching the 2nd rim to the members. As a result the twists in the wood were not pressed square for the joins and now the whole assembly is racked despite all the connections being flush and square. I may just live with this fact and attach the shelf so that the top surface is level. Otherwise I’ll be cutting new member pieces and spending another couple of hours disassembling and reassembling this piece. I will have to devise a way to press the pieces flat from all sides in order to achieve this end, however.
It’s always lovely when work was really just a dry run for getting to rework it later. No matter which side is laid flat on the ground there is about 1-1.25” twist so that one corner or the other is lifted from the ground. I didn’t have this issue wit the other frames because the frames were as wide as my work surface allowing me to clamp the rear of the assembly flat while also clamping the front area I was joining. I noticed as I moved down each member the rear was lifting higher and higher. I would have needed clamps with about 20” of throat depth to be able to clamp them. I suppose I’ll have to rip some plywood to provide an adequate work surface for the next attempt.