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Replacing the ply that the front Chainplates screw into...

Nick Mitchell

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No, have never heard of anyone doing that. Usually this part of the boat is reinforced with West System epoxy and fibreglass, so it would not ever need attention.

What makes you think it needs replacing?

Supposing the timber there has become waterlogged and rotten, I guess I'd install a hatch-cover on the deck, scrape out the rotten bit leaving as much timber as possible behind. I'd use duct-tape and sheet plastic, like an ice-cream container, to form a flat mould over the outside, then lay the boat over so that this was the lowest point. Go some carbon-fibre cloth and Epoxy resin (not Araldite or polyester), to add layers on reinforcing on the inside of the hull. When pouring the resin, it should flow through to outside and fill the mould, leaving a perfectly flat, strong repair job.

Hopefully it doesn't require anything like that! More common leak points in a timber PT are the rudder pintles at the back of the boat. An easy way to test is just watch where the water dribbles out of when you get back from sailing.

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Thank you very much for your reply and the additional information.

It's a Polyester resin set of hulls. I sent in a tiny camera to examine the marine ply where the chainplates screw into. They seem ok... but...

I removed the chain plates and tidied the area up... when I screwed them back on, I noticed that some of the screws had very little purchase. What I will do in the short term (for this summer) is inject some Araldite into the screw holes. I will investigate further how I can replace this timber.... I'd rather avoid having to install an inspection hatch! But we'll see. Pride cometh before a fall!

In respect of the transom plintels, I have gone to town refurbishing both hulls on the inside of the transom. One of the plintels had pulled out... I cut away the rotten areas and repaired with cloth and resin. I resin-ed in fibre cloth going from the small size of the hold right up to two layers almost the size of the area on the transom.

I'm very grateful for the tip on these being a high leakage area. I haven't drilled the new holes yet. I will do so and fit the plintels with great care (and silicone) based on your advice.

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Sikaflex instead of silicone; it seems to stick better and flex more, so works better in situations like that.

With Araldite; the 5-minute Araldite is not waterproof; it turns to soft jelly crap. The 24-hour stuff might be OK, but if it's a polyester hull, why not use polyester resin?

Good luck!

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If I understand the issue correctly, your boat fibreglass boat has had ply impregnated, which the chainplates screw into.

This must be similar to Laser dinghies, which have a strip of wood between mast and cockpit that cunningham plate and cleats mount to.

In the case of the Laser, when the screws pull out it's common to install an inspection port, drill through the screw holes, and install bolts with nyloc nuts and large washers or a backing plate.

Considering the chainplates hold up a huge amount of force, I'd recommend this.

Inspection ports/hatch covers are really easy; jigsaw the hole, glue and screw them in. Like this one: http://binksmarine.com.au/store/yacht-fittings/other-yacht-fittings/venturi-s-inspection-hatches/nairn-inspection-port-5

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