Hi Jeff, Regarding epoxy, I can still get my chainplates out. That’s why I put a releasing agent on them. Once the epoxy hardened, I took them back out, and now the cutouts are a better fit around the chainplates. But you have a point about movement. Next time I get in there, I’ll have to inspect for effects of that.
Regarding knees, I remember a story on this list I think, within the last few years, about a Redwing that had to be totaled due to complete destruction of one of its knees. When I did my resealing job and unbolted the chainplates from the knees, I’m pretty sure I concluded the knees on my boat are solid fiberglass. I didn’t see any wood core in the bolt holes, and there’s pretty heavy matting/roving visible on the surface of the knees. That would be in keeping with the rest of the hull construction on the early 30 MK I boats - solid glass hull, built like tanks. I also inspected the metal chainplates as best I could with a strong magnifying glass, and didn’t see any signs of hairline cracking etc. Cheers, Randy > On Mar 21, 2022, at 4:12 PM, Jeffrey A. Laman via CnC-List > <cnc-list@cnc-list.com> wrote: > > I second the sealing with butyl. Do NOT use silicone or 4200. The epoxy idea > may be ok, but messy and no going back. "Beefing up" the plates wont do any > harm but isn't necessary. These plates effectively protect the sealant. > That's it. Check the balsa core around the penetration. Depending on extent > of decay, determine how this will be remedied -- from digging out a small > amount balsa and fill with butyl to cutting out glass from above or below to > repair and anything in between. Overfill with butyl fron above and below, > then gradually tighten the cover plates to compress butyl and force it into > all voids. Carefully trim all excess butyl that oozes out from under the > plates and remove. Check frequently for leaks and gradual oozing of butyl. > > The chain plates move in and out, perpendicular to the deck under load, > unload. The sealing material must be able to move also. Epoxy will not move. > Silicone will for a while, but it's difficult stuff to remove later if it > fails. Same with 4200 but even worse. Butyl is the solution. > > Also, I encourage you to carefully inspect the knee connection where chain > plate bolts to hull. Remove bolts and poke around with dental tools. Make > sure plywood is intact and not rotting. Inspect in the bottom of the space > below knee, poking and tapping everything, checking for hollow sounds and > decay. If there have been leaks at the deck, water runs down chain plate and > into all the plywood knee structure and can damage it. So, there is more to > preventing water at the deck core. Much more. > > I am sure others on the list have stories to tell. A lister has an 81 C&C36 > that is in for a major major repair (thousands $$) of the knees due to a > leak. The rig nearly came down while racing. I was crew. Scary. So I > immediately checked my C&C34. Leaking but very little decay. Dry as bone > after butyl and 4 months -- haven't been to boat since about November, but > under winter cover. > > Jeff Laman > 81 C&C34 > Harmony > Ludington Mich > > Get Outlook for Android <https://aka.ms/AAb9ysg> > From: MICHAEL BRANNON via CnC-List <cnc-list@cnc-list.com> > Sent: Monday, March 21, 2022 5:38:59 PM > To: Stus-List <cnc-list@cnc-list.com> > Cc: MICHAEL BRANNON <ff1...@aol.com> > Subject: Stus-List Re: Chainplate Sealing. > > John, I’ve owned my 36-1 since 1997. I’ve yet to make the chainplates quit > leaking but I’ve certainly reduced the amount. First, I doubt that the > balsa around your chainplates is sealed. Mine wasn’t. I had to replace core > material on the starboard side. Second. Those aluminum trim pieces are > flush to the deck. I raised mine about 3?16” and that is what made the > difference. Lastly, Like everything else above the waterline I used butyl > as the sealant. It remains flexible and easy to remove. My advise is to > ask the butyl from both sides of the deck. Install the trim plates and see > if it is sealed? > > Cheer, and best of luck. > > Mike > > Mike Brannon > Virginia Lee 93295 > 1978 C&C 36 CB > Virginia Beach, VA > > PS, mine need to be done again this year. > > >> On Mar 21, 2022, at 5:28 PM, Marek Dziedzic via CnC-List >> <cnc-list@cnc-list.com <mailto:cnc-list@cnc-list.com>> wrote: >> >> John, >> >> Many would suggest 3M 4200, but silicone has issues. I swear by butyl tape >> (it never hardens out completely and it is very flexible). The best source >> is Maine Sail (Compass Marine https://marinehowto.com/ >> <https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fmarinehowto.com%2F&data=04%7C01%7C%7Ccb4a36365894410f988c08da0b8354c1%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637834955941777818%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=D%2FsSTOSoM9PpuLLRcc3qaZkNgrXXIzXYu0hYQVIVSvk%3D&reserved=0>), >> though, I am not sure if he still sells this stuff (he had a bad hard >> attack last year). >> >> Marek >> Ottawa, ON >> >> From: John McCrea via CnC-List <cnc-list@cnc-list.com >> <mailto:cnc-list@cnc-list.com>> >> Sent: Monday, March 21, 2022 4:28 PM >> To: 'Stus-List' <cnc-list@cnc-list.com <mailto:cnc-list@cnc-list.com>> >> Cc: johnmcc...@comcast.net <mailto:johnmcc...@comcast.net> >> Subject: Stus-List Chainplate Sealing. >> >> Hello. I have a leak on my port side chainplate that needs addressing. I >> pulled both chainplate cover plates and noticed that I had a stainless rod >> on starboard that holds the two chainplates pieces together. One on port is >> missing. Maybe that is causing excess movement and more adapt to leak? The >> covers are original and thin 1/16 aluminum. I am getting them beefed up to >> 1/8 stainless. >> >> Looks like the PO had only sealed them with clear silicone. So that will all >> be dug out. I am also inspecting the hull tabbing below with the chainplates >> etc to ensure that I do not have any issues there. What is the best sealant >> to use when installing the new cover plates? Thanks! >> >> Regards, >> >> John McCrea >> Talisman >> 1979 36-1 >> Mystic, CT >
