I used this behind my 1990 Mastercraft's rubrail.  The hull had seperated from the deck where the previous owner had bumped something and water was coming between the seam.  Also used it on all the rivet holes.  Mine took about a week to fully cure the first half of the boat that I did.  I kept the woodstove going in the shop to keep the temp up to aid in curing.  Later I read it actually cures with moisture as well as a good tempurature.  Since my wood stove/furnace actually dries the air out, I used a spray bottle and lightly spritzed water on it a couple of times a day.  Seemed to help cure the other half quicker.