Chainplate leaks.

[Gordonmc]

I am about to paint the deck again and wonder if there is any perceived wisdom about curing the leaks which accompany through-deck chainplates.
The deck is canvas over marine ply. The chainplates are mounted inboard on the hull ribs, bolted through with a rebate in the planking.
When I got the boat I had the chainplates regalvanised. On fitting I used caulking cotton and sikaflex in the gaps in the deck, but flexing now means water is getting through.
One suggestion from a yard worthy was to use neoprene or tuffnol grommets, but I can't see how that would help... and in any czase I don't want to obstruct the gap between the chainplates and the toe-rail which would stop water flowing to the scuppers.
Short of moving the chainplates to the outer hull, how can I stop the leaks?

 

[Peterduck]

Moving the chainplates to the outside will certainly cure the problem. Why is it a problem for you to move them? One measure which you may like to try is to warm the chainplates with a hot-air gun and put shavings of beeswax against them, so that the wax melts and runs down the chainplate into the gap. Keep doing it until the gap is filled.
Peter.