Thanks for the tips, FME. I was thinking about using this stuff
to seal the seams, but tyvek tape would be a lot easier and look better.
And speaking of hip belts. I've pretty much finished the base part of the hip belt, meaning I made the padded part, but I haven't attached the webbing or buckle. I hope to post a picture before too long. But, I'm not really happy with it. I think it's too short. It would probably work for me, but I'm really thin. If anyone ever wants to borrow it, it probably wouldn't be long enough to cushion their hips. I also don't think I made it wide enough, especially since it doubles as a lumbar pad. I'm going to re-do it.
I also had to re-make the shoulder straps. The ones in the picture are the second and, hopefully, final version. The first version was based on the G4 "J" straps, but I made they WAY too big. Here's hoping making everything twice won't be a continuing pattern.