Chain Plates

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JHubb
Posts:19
Joined:Wed Feb 26, 2020 5:13 pm
Chain Plates

Post by JHubb » Wed May 20, 2020 6:00 pm

I have a question about the SJ chain plates.
The outside looks pretty rough and in need of attention.
On the deck, the cover is riveted on.
On the inside, it is glassed over.
How do i go about making sure everything is in working order?
Drill out the rivets?
Cut out the fiberglass?
I've included a couple of pictures.
Thanks for any help,
Jeff
Attachments
Chainplate Int.jpg
Chainplate Int.jpg (39.85KiB)Viewed 13816 times
Chian Plate 1.jpg
Chian Plate 1.jpg (170.25KiB)Viewed 13816 times

kingtoros
Posts:33
Joined:Mon Mar 18, 2019 7:51 pm

Re: Chain Plates

Post by kingtoros » Thu May 21, 2020 5:18 pm

This looks like a Mark I expert question... On the Mark II and III, the chain plates are mounted to bulkheads. See my post here of what a refurb on them can look like: viewtopic.php?f=16&t=10359&p=14111#p14107

On that note, I think the metal should be fine if they're holding weight? Perhaps some silicone? I'll let the Mark I guys give their advice.

kuriti
Posts:243
Joined:Tue Sep 13, 2011 12:48 am

Re: Chain Plates

Post by kuriti » Fri May 22, 2020 12:29 pm

I would drill out the rivets, then remove the chain plate. Using the bent nail method, drill out all the wood to about 1/4 inch past all four corners p, so you have a 2x3”ish void. Tape up the hole from the bottom, Mix up epoxy and colloidal silica to a mayo consistency or slightly thinner. Pour that in and poke at it to get rid of any air. Then drill and dremel/sand a new hole for the chainplate. You can use the cover plate as a template for where the chainplate goes. Replace the cover plate held with small stainless screws. Fixed for life.

This is how I handled mine and all through hull fittings. This way when (not if) they start to leak, it doesn’t really matter other than water in the cabin. If you aren’t familiar with the bent nail method, happy to elaborate.

Also, with respect, don’t ever use silicone on a boat. Use 4200 or 5200. Silicone is impossible to remove and when sanded just contaminates everything around it making it impossible to paint or get an epoxy bond on that piece of fiberglass in the future. There are some exceptions for portholes, but better alternatives even in that situation.

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Gman377
Posts:58
Joined:Sat Dec 02, 2017 2:03 pm

Re: Chain Plates

Post by Gman377 » Thu May 28, 2020 1:43 am

I did mine exactly like Kuriti did And I have had no leaking through the deck where the chain plates go through, that is definitely the way to go. I ended up taking the wooden bulk heads out and I found some quarter inch steel that I made into these bulk heads (see attachment below). I cut them and welded them and had them powder coated so they will never rot like the original bulk heads. And it really opened up to the cabin space:
download/file.php?id=336

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