And then there was Proseal. Vans’ instructions cover this process pretty well, and I used Dan Checkoway’s narrative as well to help visualize the process.

It’s really helpful to have everything you need in one place before doing any mixing and sealing. I found a relatively cheap digital scale which made it relatively easy to measure out the Proseal. I also spent a fair amount of time cleaning the skin and stiffeners with MEK to get them nice and clean. It’s important to have lots of latex or nitrile gloves – you’ll need ’em. Also have lots of rags and MEK (or naptha) on hand for cleanup. I also put a couple dozen rivets in a glass jar with some MEK to keep them clean.

There’s not much I can add to Dan’s process, so I won’t try – except to emphasize the difficulty in checking shop heads on the back-riveted stiffener rivets. There’s one rivet there I’m not proud of on the right tank skin, but it wasn’t worth the trouble to drill out – and it’s covered with Proseal anyway. Here’s my first attempt at tank sealing…