Ten Degrees of Bench Building
After a few weekends out of town and my time in the shop kept to a minimum, I finally had some shop time this week to really make some progress on my latest original design. Working from the 1:5 scale mock-up has really made the process go smoothly. I definitely see more small scale mock-ups in my future as a key part in building my design chops.
The ten degree angle is a repeated design element on this bench. The tenon shoulders, leg tapers and even the exposed end-grain elements on most of the vertical parts carry a common ten degree angle. Part of this is due to allowing the end grain to quickly drain off any water – this is because the bench will sit outdoors. I worked in a bit of a hybrid technique for cutting the ten tenons for the three cross braces. I initially cut the cheeks on a table saw tenoning jig, but their size started to get a bit unwieldy when making the adjustments to remove the waste accurately.
I thought of a technique I’ve seen Jeff Miller use when cutting tenons for chair parts. It uses a combination of a corresponding block of wood cut at the angle intended for the cheeks, then clamped against the workpiece and cut with a flush cutting saw. The block was simply an off-cut from my chop saw when I cut the cross pieces ten-tegree angles.
The technique worked perfectly, and only required a bit of finessing with a chisel. The clamping block serves as a consistently flat reference surface for both the flush cutting saw as well as a chisel. Having the split-top Roubo workbench didn’t hurt either when clamping the piece down to a comfortable position.
I’ve begun to dry fit all of the major parts, including the vertical arm braces that will support the large slab arm-rest pieces. It’s starting to look a lot more like the 1:5 scale prototype, but much, much heavier. The next step is to begin cutting and fitting the seat back, and arm rest elements, all coming from a single massive sapele board.