While I wait for fuel plumbing to arrive in the mail, I'm attempting a saddle from a few layers of neoprene rubber glued down to a fiberglass substrate which will then in turn velcro to seatpan that nests onto the frame. Some rainy day I'll upholster the assembly but for now it'll just be raw foam.
I'll form the 'glass substrate directly off the seatpan using my usual processes. Begins with a layup formed around the contours of the seatpan. I'll then attach foam rubber to the resulting part. Here I've prepped added some cardboard reliefs for the seatpan's mountpoints and prepped with tape&PVA.
Before gluing up the foam, I epoxied a bunch of 1/8" ID washers and drilled out their interior holes so that I have some support for pop-riveting the seat cover in place. Not sure I will need this or not but figured it was an easy enough thing to do, might as well.
I used a glue called "Barge Cement". It's a wonderful glue that I use whenever I need a really strong, yet pliable glue for soft/porous materials like foam (or bicycle handlebar tape, or shoe repair). Its process is much like contact cements where you apply to both faces, allow to dry for some minutes, then press together.
Here's teh second layer. Looks kind of rough but If I'm going to cover it, then it will be okay. One noteworthy item is how quickly the foam dulled the Exacto blades I used to cut it. Really amazing.
Another gratuitous profile :-)