Well, the title says it all ... a saltwater boat and salt WILL attack and corrode rivets, thus the boat will leak ‘someday’. That 'day' turned out to occur this year, but I do leave my boats out in the salt 24/7 at my boat club dock.
This is my old 14’ boat, as I had sold it to a kid ~5-years ago, and it wasn’t leaking when I sold it to him. He had completely stripped it and applied Steel-Flex, as he too used it in the salt, but we found out a crucial lesson. On this hull there is a hard domed or ‘V’-chine or rib that forms the keel going down the center of the boat. This is designed to be open and there are a few factory ‘weep’ holes in it, but he closed them all up with the Steel-Flex, doh – not a good thing to do! He bought a new boat this season and was so grateful that I had helped him out through the following years of his ownership (like tuning the motor or changing the impeller, even general boating & fishing advice) that he sold it back to me for about ½ what it was worth.
The rest of the hull is integral - no leaks anywhere. Thus ... with the small leak/weeping ... surgery has commenced! Look at the water weeping out of the keel section, so one can see it was getting trapped in there and not draining. My plan is to remove that keel section, clean it and the hull (also inside) up really well by mechanical sanding and white vinegar washing, then prime with 2-part self-etching epoxy-based tin primer, then reassemble and re-rivet it with closed rivets. I’ll use LifeCaulk or 3M 5200 as a sealant, with the piece held in place with Cleco fasteners as the re-riveting begins.
KEY Tips for the Repair – Most factory OEM rivets are 3/16” in diameter, but I don’t drill them out with that size drill, as I want my hole to remove them to be smaller. I drill the heads off with a smaller (like 9/64” or /32”) sized drill. Then is done so when I finally re-drill through for the new rivets, using a new cobalt 3/16” drill bit, a get a nice clean, sharp hole for the new solid rivet.
- Clean the rivet area well so you can see where you’re working; I used a sharp 3/8” wide chisel to cut through the Steel-Flex as shown – [Picture Step 1]
- Use a ‘prick punch’ (not a ‘center’ punch) to mark the center for the drill – [Picture Step 2]
- For this many rivets, only use sharp new drill bits, cobalt recommended, where a heavy feed and medium RPM cuts the best – do NOT burn out your drills. I also keep a catfood tin of cold water handy to dip the bit into.
- Drill through the rivet head only! Don’t try to drill the rivet out entirely! Again, I use a smaller than 3/16”drill bit to drill off the old rivets – [Picture Step 3]
- Sometimes, like 1 out of 3 on this repair, the rivet head sheers right off due to the drilling – you get lucky! – [Picture Step 4]
- Otherwise put that same chisel on a low angle and one solid punch should sheer the head right off
By partially drilling through the head, if your pin strike was off or the drill bit drilled off ... now you can “see it” well before you completely drill through the hull/rivet and now you can adjust your drill hole. Either re-punch the remaining rivet to get on-center, or tip the bit to drill through, targeting the center of the rivet.
Stay tuned for more pictures as this repair progresses ...