I have seen posts in these forums for the use of 3M 5200 adhesive to seal gaps, for example, between strips in a strip-built, all-wood canoe. I had never used it but recently found an excuse to give it a try (not on a canoe). It has now been 3 days and this stuff can still be smeared around with a fingertip! How long does it take 5200 to get hard? What I have learned is that if you are in a hurry to move on to the next step, don't use 5200. Tom McCloud