It doesn't matter that you rebuilt your boat from the ground up or sailed the Caribbean, when I tell a fellow sailor I patch my sails with 3M 5200 fast cure they lose a little respect for me. Well that's fine because it is fast, easy and it just works. And before they recover from that, I tell them I patch our hypalon dinghy with it too. Thou I do know how do these repairs correctly, this just works better.
Early on, for large sail repair jobs I would have to remove the sail, find a location to lay the sail out that also had 110 volts ac to run a sewing machine. Or find a loft that could do the repairs. This option was not possible with the sailing we have been doing for the last few years. For the smaller holes and ripped seams I would have to hand sew the heavy dacron material. Often multiple layers. The sewing is difficult and adds a perferated row that weakens the sail that is asking to rip again.
Enter 5200. This product was at one time my enemy. It's most often used as a bedding compound but it is difficult to remove and will leak after a while, so I use butyl tape (that is another post). As for sails it is a perfect match. I have even started calling it "Liquid sail." For holes I cut a dacron patch and glue it down. For blown seams I simply spread it in the seam and put push it together and let it cure for a couple hours. Done. It is flexible and UV resistant which makes it great for patching holes in our dinghy too. I will not even begin to write about the "proper" way to patch hypalon dinghy material, but will say you nearly need to have a doctorate in chemistry or you can deflate the tube, scuff the area with 60 grit sandpaper, smear on some 5200, wait a couple hours and inflate. For a nicer finish I apply a patch of pvc with the 5200, but usually I use the smear technique because it is best not to have the nicest looking dinghy at the public dock.
