My chainplates as epoxied into the deck!?

KompetentKrew

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Hello,

I have to inspect and (surely) replace all my chainplates.

I wanted to do these midships ones first because their fabrication seems more complex - it appears to be a stainless steel tube welded to the flat SS plate at each end.

However I cannot remove it - it appears to be epoxied into place. I was surprised by this - is this common?

My boat is a Van De Stadt Caribbean 40 - it was built in the 90's by a small Dutch jachtwerf. It's epoxy composite, and I believe the deck is ply.

Video:


Pics:

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I have tried hitting the top of the two of the chainplate with a hammer and all that happened was that I split the block of wood I was using to protect the top of the chainplate from damage. I guess protecting it from damage doesn't really matter if I'm replacing it, but I was hitting it bloody hard and I don't think it would make any difference at all if I was doing so with the hammer directly on the chainplate - my blows were just bouncing off.

So far my best idea is that my multitool has a fairly fine cutting blade, like 1cm wide, and to use this to kinda "edge" around the chainplate and cut it from the deck.

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Does anyone have any better suggestions for removal, please?
 

RunAgroundHard

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I think nibbling away at the glue with a multitool blade as you suggest is likely the easiest solution. Don't force the blade, because it is easy to deflect and cut away from the slot. Let the blade do the work without significant effort.

Screws epoxied in place can be removed using a soldering iron placed on the screw head to soften the epoxy, but before resorting to a scaled up version of that, such as with a blow torch, defo try and cut out the glue.
 

Tranona

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Unusual but seems a good design as it avoids a flexible joint at deck level that often causes problems with leaks and crevice corrosion where the strap goes through the deck. No sign of that at deck level because of the epoxy sealing the deck and presumably good sealant under that cover plate. Why do you want to change them? Can't see any signs of corrosion or water ingress and the attachment at the lower end looks sound. To replace I would imagine you would have to cut out the deck around the exposed plate, although it is not clear whether the tube is part of the strap or just a cover. Don't think any loads re taken by the deck, but go straight down to the knee the lower end is bolted to. Presumably that is connected to some sort of bulkhead under the berth to transfer the loads over the hull structure.
 

KompetentKrew

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Well, I assumed corrosion.

You can certainly see rust staining lower down. Here's the foot of the chainplate:

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You can also see obvious water ingress on the adjacent chainplate:

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It looks like that one may also be epoxied?

I was hoping not to have to admit this, but the chainplates suddenly became a priority because this second chainplate actually broke in a storm, whilst I'm on the hard:

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RunAgroundHard

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Admitting the breakage is not a problem as it gives context. Because off the breakage, they all need to be removed and all inspected. It looks like quite a simple design. I wonder if it could be improved by having it made from solid rectangular bar in one section, rather than welding onto a tube. This is how some inner forestay chain plates are made, straight through the deck and onto the hull, no transition pieces. Inside they could be covered with vinyl backed foam to match headlining, or just polished to leave a handhold.
 

Tranona

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OK your new photos make sense. That is a common problem with through deck chain plates as I described. The seal failing at deck level and creating crevice corrosion conditions where the strap goes through the deck. The difference with yours is that the seal through the deck is a solid epoxy mix rather than the more common sealant such as Sika. The answer to removal is the same - the sealant/epoxy needs to be cut out so that the strap can be drawn out from below. Hopefully water has not got into the ply deck. Maybe a redesign of the strap as one piece as suggested. Not as elegant as the tube. However once you have it out you may find it is sound and only need cleaning up and replacing with a good sealant at deck level rather than the solid epoxy.
 
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