I kept thinking about everything I didn't like about the seat I made (henceforth "the prototype") and realized that all its issues stemmed from me making simple stuff complicated. Stuff I did wrong:
-Made a full pocket for the bump stop. This meant I couldn't pull the material taut.
-Made it out of waaay more pieces than necessary, which meant I had to figure out lots of seams, plus multiplied my chances of screwing up. On the new version, I only used 4 pieces of leather.
-Glued patterns to the backs of all the pieces. This meant I had all that paper to deal with, and also the glue made everything want to wrinkle and pleat. On the new one, the only glue I used (3M 77 spray) was to stick the foam on the back of the seat top.
-Figured out a stitch length that looked cool for the pleats and then stuck with that. This resulted in pretty weak seams. On the new one, I lowered the stitch length after I did the pleats, plus I did double hems.
-Went to lots of trouble to measure out 1/2" hem margins on everything. This time around, I just drew the seat top and bump stop on the foam with Sharpie and cut it out 1/2" outside of that. Somehow it didn't occur to me yesterday that A: the hem margins don't have to be super exact, and B: I know damn well what a half inch looks like. Once I had done that, it was just a matter of sewing a 3" wide strip of leather onto the seat top and another onto the bump stop, leaving 3" X 3" tails on all 4 ends. Sew the resulting 2 pieces together, and Bob's your uncle.
It still ain't perfect, but I won't be embarassed to put this on my bike:
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