Cape Dory 36 chainplate issue: would you buy this boat?

[Cpt Pat]

I'm looking at an original vintage (hull number less than 71) Cape Dory 36 cutter.

Everything looked good - until I inspected the forestay chainplate belowdeck backing plate and anchor assembly (Cape Dory owners call this contraption "The Thing") in the bow chain locker. This vintage of CD36s used a mild steel plate, with welded rebar at the apex of the bow. The rebar is glassed in to anchor the chainplate backing plate and transfer streeses to the hull - not the deck.

Because the rebar is surrounded by glass, I can't see its condition. I can only see that the plate is corroded and that the plate has deliminated from the bottom side of the deck - presumably due to rust swelling under the plate. (Photos below: note the streaks of rust.) . If the plate fails or the rebar loses its bond with the hull, all of the stresses will tranfer to the deck, and the deck will almost certainly fail catastrophically without warning under that tension from below (not to mention the consequent dismasting).

Later Cape Dorys used bronze or aluminium because of the corroision issue. I suspect removing and replacing the plate would be a costly and major project. If I replced it, it would be very challenging to get a primary bond to the hull. The only practical correction I can envision is a conversion to an external stem, which would interfer with the boomkin.

All other things being equal, would you buy this boat? And if so, what would you do about the rusted and deliminated plate?

Thanks in advance for any opinions!

[Sailmonkey]

From the photos I don’t see anything particularly alarming, but then again lots of things look good in photos.

To me that doesn’t look like that massive of an undertaking to replace even if required.

[roverhi]

As Sailmonkey says doesn't look all that bad. From photos looks to be just a plate with a rebar welded on and a vertical. If the rebar was to carry the load out to hull via the flange for the deck doesn't look like it would do all that much. the vertical fin also seems questionable for benefit. If I was worried about the vertical pull of the stay bending the plate would have welded athwartship piece(s) or had athwartship channel pieces that the head stay fixing bolts went through and extended out to run under the deck flange. Doesn't seem to be much benefit from bonding the weldment to the deck. The weldment, for being mild steel, is in surprizingly good shape for its age. There has been very little, if any water leakage to cause corrosion. A tribute to the builders who did a good job of beddeing all the hardware on deck.

Would add it's very hard to see from the pictures what the exact condition of the piece is. Pictures never lie unless they do.

[Orion Jim]

Looks pretty solid after thirty years.

[rognvald]

The CD 36 is a great boat. However, if I were to buy this boat, I would have a marine engineer analyze the problem and give a quote for a professional repair before purchase. Then, unless you like projects, I would make the repair a condition for the sale with an independent engineer certifying the job after completion. Best, Rognvald

[Delfin]

Originally Posted by Cpt Pat

I'm looking at an original vintage (hull number less than 71) Cape Dory 36 cutter.

Everything looked good - until I inspected the forestay chainplate belowdeck backing plate and anchor assembly (Cape Dory owners call this contraption "The Thing") in the bow chain locker. This vintage of CD36s used a mild steel plate, with welded rebar at the apex of the bow. The rebar is glassed in to anchor the chainplate backing plate and transfer streeses to the hull - not the deck.

Because the rebar is surrounded by glass, I can't see its condition. I can only see that the plate is corroded and that the plate has deliminated from the bottom side of the deck - presumably due to rust swelling under the plate. (Photos below: note the streaks of rust.) . If the plate fails or the rebar loses its bond with the hull, all of the stresses will tranfer to the deck, and the deck will almost certainly fail catastrophically without warning under that tension from below (not to mention the consequent dismasting).

Later Cape Dorys used bronze or aluminium because of the corroision issue. I suspect removing and replacing the plate would be a costly and major project. If I replced it, it would be very challenging to get a primary bond to the hull. The only practical correction I can envision is a conversion to an external stem, which would interfer with the boomkin.

All other things being equal, would you buy this boat? And if so, what would you do about the rusted and deliminated plate?

Thanks in advance for any opinions!

Attachment 178998

Attachment 178999

Yes, I would buy the boat if this is all that concerns you. Owning it, I'd spray or paint on Ospho, rinse, then, sorry or paint a good 2 part poly paint. Better yet, I'd make the the current owner have it done by a yard as a condition of purchase.

if the rebar is fully encased, it hasn't rusted.

[Group9]

That desn’t look that bad, or even that hard to fix if it did turn out to be bad.

[guyrj33]

it does look like there's a leak above the plate that's causing the rust.
The damage doesn't look all that bad now, but if left unchecked will become serious.
As to repair, i'd start by stripping the deck above and try to get a rust neutralizing (phospo) in between the plate and the deck. Sand blast and paint everything than reassemble carefully sealing deck hardware.

[Cadence]

Originally Posted by Sailmonkey

From the photos I don’t see anything particularly alarming, but then again lots of things look good in photos.

To me that doesn’t look like that massive of an undertaking to replace even if required.

it may be a needle in a hay stack. Cape Dory made a good boat.

[NevisDog]

Originally Posted by Cpt Pat

... (Cape Dory owners call this contraption "The Thing")... If the plate fails or the rebar loses its bond with the hull, all of the stresses will tranfer to the deck, and the deck will almost certainly fail catastrophically without warning under that tension from below (not to mention the consequent dismasting).

Later Cape Dorys used bronze or aluminium ...

All other things being equal, would you buy this boat?

Cape Dory 36: with everything I've read about these boats - I'd buy it, no hesitation - but one of the first things I did on buying my current (not a CD) 33' was replace the under-spec stem fitting with heavier gauge stainless. I didn't ask the PO to do this as he crossed every ocean without any concern for that flimsy fitting, so I don't think it's the current owner's problem; looks plenty strong at present. I'd question the use of aluminium here too though.

So, just curious, what holds that flat wooden bowsprit in place on the CD36 - all those little bolts? It must be pressing back against an anchor windlass or deck fitting to take the forestay/bobstay compression loads, surely? From photos, both versions have a tang or bobstay running down towards the waterline from the end of the bowsprit, which appears to have multiple attachments through the deck, so it can't really "fail catastrophically" - it has plenty redundancy (especially the cutter version). I'd be really surprised to learn of any "catastrophic failures" of CD36 stem fittings, though it's worth asking around.

So, it doesn't look like an urgent repair. Personally I'd look at ways of bypassing "the Thing" by through-bolting the inner stay down to an internal stainless strap bolted to the lower stem where the bobstay attaches, like an extra chainplate for the inner stay. Then I'd toss some rust-kill on "the Thing" and leave it to enjoy its retirement. Just a suggestion, there's always more than one way to swing a cat - maybe there are even simpler repairs that CD36 owners can recommend.

[vonchris7]

I'm doing the exact same project on my Cape Dory 36 right now (hull No. 50).

Mine looks much worse than yours. It is a big job.

Here are some links to the Cape Dory owner's association from others who have done this:

The Cape Dory Board • View topic - Bow Sprite Replacement Project

The Cape Dory Board • View topic - What sealant to use between bowsprit and the deck?

The Cape Dory Board • View topic - Steel Bow Plate

The Cape Dory Board • View topic - Steel Bow Plate

Hope this helps.

Chris

[Benz]

Totally not a big deal. I would bypass it if it was too big a pain to grind or cut out, but my vote is for removal, glass over the damage, and engineer something better.
If the boat is a good price and you want it, don't let a detail like that deter you.
BTW, a "boomkin" is usually a framework aft that carries the backstay beyond the transom on marconi-rigged boats with long booms. Never heard it used for a bowsprit or bowsprit plank.
An inspirational blog about a CD 36 refit: farreachvoyages.com

[SSgtPitt]

I agree, farreachvoyages.com is a helluva site.
When you get done looking at the bow, go check out what’s holding up the Perkins engine. Climb in there and spend some time.