Chain plate/Bulkhead help please.

[Jimbocky]

No wonder I couldn’t get the screw out.

 

[Jimbocky]

5 hours later.

 

[tenders]

Here's the documentation of a fix I made to my bulkhead rot problem 16 years ago. I basically cut a trapezoidal shape out of the bulkhead removing all the rotted area, and glassed in a 1/4" G10 trapezoidal replacement patch using eight layers of fiberglass.

I'd do it again like this somewhere else if I had to. Hopefully I won't have to.

Chainplates and Bulkhead - replace?

I had the same issue on my boat - minus the chainplate fissure - and successfully scarfed in a new section, which through periodic inspection, has proven sound. Knock on 'wood.':rolleyes: Fortunately, the rotted part was only the girth of the salon chainplate covering box, so I didn't have to...

ericsonyachts.org

 

[Jimbocky]

I now have full access to the bulkhead. Is there a material that is waterproof to replace the plywood.

I plan to properly reseat the chain plate.

Thanks for all the feedback.

 

[Pete the Cat]

True marine plywood should be fine. The bulkhead tabbing looks sort of wimpy to me. I this a lower shroud chainplate? I think you are going to be visiting a metal shop for the deck plate anyway so getting a new chainplate made might not be a big deal in the scheme of things--you can reuse the SS backing plate. As I look at this, I think your best bet is radical surgery of the bulkhead and splurging on some metal work. This is probably one of the most important structural points on the boat and you do not have a lot of furniture you are trying to save.

 

[Jimbocky]

Yes a lower Shroud. Marine plywood would be a huge upgrade from what is originally there. Thanks.

 

[Prairie Schooner]

Yes a lower Shroud. Marine plywood would be a huge upgrade from what is originally there. Thanks.

Impressive progress, Jim.
Plywood is a remarkably strong material. You can seal it in penetrating epoxy. Most critical is end grain. The grain is like a soda straw and sucks water by capillary action. When I replaced our sole I used .25" T&H ply laminated to .75" marine plywood. Once all cutting and drilling was done I saturated the panels in thin epoxy. Others have reported good protection with this method, as well.

 

[jim faugust]

When you say better, do you mean for strength, aesthetics, price, or something else?

1. Is the deck sound in the area through which the chain plate passes through. I had machined an oversized backing plate cut to slide up the chain plate to the underside of the deck where it was tapped to receive threaded bolts from the deck above into the into the backing plate. You may want to consider a gasket above the underside plate so as to be able to draw it up snug. As for the bulkhead cut out the bad stuff and replace it a plywood backing plate, oversized to spread the load, fill in w/a dutchmen fashion, glue and screw it back together and refasten your chain plate.

 

[gabriel]

Is there a way to detach and float that top plate short of having new ones made.

yes, that’s how my e25 is, the plate is separate. Harder to seal though. I would just have the CP remade, prob not worth grinding off, especially if they might need replacement anyways.

Also isn’t there something better than marine grade plywood to replace the bulkhead with?

There really isn’t, everything is either heavier, weaker, more expensive etc.

Consider baltic birch plywood before buying marine ply for bulkheads. the 1/2 is stuff is 9x ply’s, stiff and very high quality with no voids. It’s somewhat heavy. Also comes in 1/4“ and 3/4”, all metric so not exactly, but very close.

 

[Jimbocky]

Thanks. I already ordered marine grade. $150 for one sheet.