HELP, mushy plywood under bow chainplate - SailNet Community
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post #1 of 8 Old 04-20-2019 Thread Starter
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HELP, mushy plywood under bow chainplate

8.5 hours at yard yesterday accomplishing much prior to spring launch.

Then, 0.5 hours of SCARE--

Anchor roller at bow loose. Next to the anchor roller is the horizontal / deck portion of forestay chainplate. See the attached photo.

FYI, this is a 1982 Catalina 30.

I decided to explore bolt access for these two fixtures. I found that all bolts accessible in anchor locker (albeit a bit tough to reach since they are well forward).

While feeling for the bolts I felt water. I poked a bit and pulled glops of mushy wood out with my fingers.

ADVICE PLEASE! I am a bit freaked out to say the least!!!!

The goal of this post for me is to learn about the early 80's Catalina bow anatomy and potential fixes. I also posted to the C30 forum.

So, please, if you can speak knowledgable about related things, then I eagerly await (and also appreciate) your advice.

Here has been my train of thoughts over the last 12 hours (some rational, some irrational):
  • Oh no, yard will cut off bow and completely rebuild it for purchase price of the boat. I will not be in water until July.
  • Mast is gonna come down to fix, so $$$ (~$700 for unstep/step near me) on top of the $$$ for the actual repair.
  • Can the mast stay up with the forestay disconnected (i.e. use a halyard attached attached forward during the repair.
  • Maybe deck can be repaired from underneath. No mast unstep necessary. It will take long arms and mirrors to access it in the anchor locker.
  • Maybe, just maybe, the wood is just extra support.
    • This is what I am really hoping!
    • I read this online somewhere about another boat make (ha ha it must be true if it's on the internet).
    • Theory is that the plywood is extra beef for the deck at this critical area.
    • If this is the case, then maybe the glass is just fine. This could be why the chainplate feels solidly anchored despite the mushy wood in the area.
    • Then again, the chainplate could be stationary because of the bolts securing it "around the corner" on the part of the bow that angles down to the water.
    • If the real anatomy is plywood as extra support, then I hope the mushy stuff can be picked out, new wood epoxied, and then good to go....
I eagerly await your input. Thank you.
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post #2 of 8 Old 04-20-2019
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Re: HELP, mushy plywood under bow chainplate

Not sure what you are dealing with but I did do a complete refit on my boat and for the most part it was removing the mushy wood and replacing. Using some kind of epoxy mix to fix and strengthen. Just get in there take it out and put in new stuff it will give you peace of mind in the long run. The other side of the coin would be what an Old sailor told me just go sailing till it breaks then fix it. The other one was is held up for 30 years just patch it up and keep going. Regardless of good luck and my personal experience has been things that look really bad end up not being as big of a deal as one might think.
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Re: HELP, mushy plywood under bow chainplate

I hope it's as you say--remove and replace mushy wood.

I appreciate your experiences--usually there is a solution and I hope I'm experiencing "simply" fear of the unknown.

Some things I use until they break. in this case, a break can mean dismasting. So, I'm inclined to fix now.

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Re: HELP, mushy plywood under bow chainplate

Just a guess!! and from looking at some photo's of Catalina 30's. Your Chainplate should extend down the bow, likely solid glass, and be thru-bolted. Not sure what they used as a backing plate, I would hope another stainless bar. I'd also guess that the wood you're pulling out is some kind of backing plate for the anchor roller and the top attachment for your fore-stay.

You'd have to get in there to remove all the rotted wood, clean up, and then fabricate a new backing plate. I think I'd want to make a wood model to align the holes, then perhaps get a machine shop to fabricate one from the model using stainless.

As far as removing the mast, If you're in a cradle you could secure the fore-stay to that with strapping that you can tension. I've done that with shrouds, while replacing bulkheads. Otherwise, you'd need to secure it to something. You could probably get everything cleaned up and fabricated before you get set to install, minimizing the time needed to secure the stay.

You'll probably want to lift and re-bed the anchor roller. That water was getting in from somewhere.

Just an Arm-Chair guess.
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post #5 of 8 Old 04-20-2019
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Re: HELP, mushy plywood under bow chainplate

I am guessing that the anchor roller was added by a PO and used plywood as a backing plate. If so, this will be a (relatively) easy fix.
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Re: HELP, mushy plywood under bow chainplate

Paint us a picture of the underside of the bow where the bolts for your stemhead (the chainplate attachment at the bow) go through the deck. If the underside of the deck looks like fiberglass with the bolts coming through and nuts on them then we are talking deck core that is rotted and not just a backing plate as mentioned earlier. A backing plate would not be sandwiched into the deck, it would be exposed.

The issue with rotted core in a structural area like this is that it's meant to bear the upwards pulling force from the forestay. That force is supported by the nuts on the bottom of the stemhead bolts, and then to the underside fiberglass layer, then through the core, and to the top layers you see on the deck. If the core is rotten then you essentially only have the 1 thin layer of underside glass supporting those nuts\washers. They could pull through would be your worst case, and since we are talking forestay here, would most liklely result in a dismasting.

Yes the forward edge of the stem head is bolted to the bow, and should be strong, however the bolts on the deck are there for a reason and weren't put there just for looks. It's not often production boat builders added extra parts\work without reason.

You won't need to pluck the mast most likely, as long as you can secure it with a halyard or two as far forward as possible. When I changed the stemhead on my Mirage 33 I used the main jib haly and spin haly to support my mast. I ran them as far forward on the toe rail as I could (about 6" short of where my forestay attached) and winched them up tight. The mast never moved. I would not rely on a single halyard to hold it, but that's just me being extra cautious. If you are in a rolly marina, and are already in the water, and your fix may take a few days to do, you may consider plucking the mast.
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Re: HELP, mushy plywood under bow chainplate

If you could pull out handfuls of mushy wood, it does sound like a plywood backing as previously suggested. Biggest challenge is the boat-yoga required to fit into the anchor locker to replace it - preferably with something rot-proof.

Also, you can remove a chain plate without pulling the stick if you have to. You just loosen the standing rigging, then use a halyard tied to a suitable point (like a cleat) to take the load off the chainplate you need to replace and voila!
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Re: HELP, mushy plywood under bow chainplate

If you give Catalina a call they can probably tell you how that part of the boat was constructed. If you are lucky the stemhead is bolted through an area that is solid glass. I agree that the roller may have been added by a PO (and not bedded properly to keep water out).
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