Patching from the inside, I applied some liquid electrical tape, and then I folded the bellows and wiped off the excess a few times. Seems to work it in really well... It's doing a brilliant job so far, and from the outside of the camera it's impossible to tell. It doesn't seem to be making the camera any harder to open, but i'll have to wait for it to dry completely. This stuff is just the ticket for fixing my 8x10, we'll see how well it works on a camera that folds it's bellows very tightly soon...