Has anyone had a CD chainplate failure?

[Russell]

One of my big worries on my boat is chainplate failure. The CD chainplate setup is rather unusual, and its use of mild steel as well as the lack of visability to much of the system makes it a cause of worry for me. I know a lot of boats who have experienced chain plate failure while underway or when investigating found chainplates ready to fail very soon. But oddly I have not heard of anyone on this board, which shares a lot of info pro and con about our boats, ever having a chainplate fail.

So, I am curious, has anyone experienced failure, or found theirs in need of serious repair? Most of our boats are at the age where chainplate replacement is typically done, so I am suprised to not hear much about it here.

[Sea Hunt]

Russell:

In the February 2007 issue of Practical Sailor there is an article about marine metals and their degradation, including what to look for.

The article's author, Ralph Naranjo, apparently owns a Cape Dory Typhoon (not clear if it is a daysailer or weekender model). His article shows a photo of what was left of one of his chainplate backing plates. At page 30, top center photo. As the article described it, it really did look like "cornflakes". Mr. Naranjo was sailing and a bolt from the starboard chainplate snapped when the backing plate (now cornflakes) could no longer support the stress.

He was fortunate to be able to quickly take corrective measures and save his rig and CD. Had it been me at the helm there is little doubt of the results - a sunk CD and a barely floating skipper.

Mr. Naranjo suggested that "mild steel" was used instead of stainless steel for the backing plates. Practical Sailor at page 29, middle column.

There is also an article/letter in Good Old Boat July/August 2007 from Jule Miller about steel degradation in her CD 22.

Lew Gresham also posted a picture of a crumbling metal chain plates on 15 February 2007on this board. His post was titled:

"Chain Plates + Backing Plates + Rusted Out!"

[Lang]

The 1st time I raised Eleanor mast, the chainplates pop out from the deck. After looking, we found that the backing plate was rusted gone and the bolt was hanging loose with a stack of washers. The bolt broke in the middle and out goes the chainplate.

The original chainplate itself was in excellent condition. We replaced the bolts with bronze bolts and a new stack of large diameter washers.

[bill2]

FWIW

Awhile back ( around 2 years ago maybe ) I was on a reasonably well kept cd27. The average person would question the rust streaks on the inside of the hull beneath the chainplates. I surmised they must be an early warning sign of things going seriously awry at some time in the not to distant future - at least IMHO. I suppose they could fail without leaving the streaks also ?

Fenix' solution appears much more elegant by comparison . . .

[Greg Kozlowski]

Hi Russell,

When we bought Sherpa I went over everything, including chainplates with the thought that we would be doing some serious ocean miles.

When I inspected the chainplates, it was clear that one of the portside chainplate thrudeck bolts had been leaking. This, in turn, badly rusted the mild steel in the chainplate underneath. I brushed back all of the rust as much as possible, treated it with Ospho and added an additional 1/4 inch SS plate of the same dimensions over the rusted piece and replaced the thru deck bolts.

I strongly suggest that you have a look at your chainplates if you haven't yet. Their condition wil be immediately obvious upon inspection from the inside.

Best regards,

Greg

[Neil Gordon]

Had it been me at the helm there is little doubt of the results - a sunk CD and a barely floating skipper.

Let's not overstate the outcome. Chainplate fails, mast falls down. That's it. Usually it takes more than one thing going wrong to sink a boat. (Sometimes, it's what the skipper does to fix the first thing that causes the boat to sink.)

[fenixrises]

Hi All,

While this topic has been talked about at length it is a good one to review.

Many of you may find the repair-replacement of the nefarious steel backing plates to be a bit daunting. This need not be so, BUT be prepared for a bit of work.

#1 problem is access. If your boat is like mine, trying to do the work through little holes in small lockers is near impossible and a real struggle. My suggestion follows.

Most people would prefer to retain the appearance of a smooth sided hull and not opt for exterior thru bolted chainplates. In either case you should realize there is going to be a bit of surgery required to make the task far easier.

In my case removing the head furniture and hanging locker face and top was easy. The plywood was not glued to the cleat stock and the cleat stock was not glued to the bulkheads. Even the teak plugs in the screw holes were not glued in place. Therefore with some careful work the "offending" interior parts can be removed.

Then real access is possible. Some of you may gag a bit at this but the next step is to cut out a bit of the liner that is normally inside the lockers. The cutouts do no need to be deep vertically, say 6-8", but should be as long horizontally as possible. Now you have the room to work. Simple painted plywood panels can be fabricated to cover the holes. Design them so as not to interfer with the original plywood. Yes you need to put on your thinking cap to pull this off.

Although in my boat a semi-fix was done by a PO the evidence left behind is that the original steel plates were NOT encapsulated in f/g. They were held in place by mish-mash until the pad eyes were installed.

Your cases may vary but with sufficient elbow room removing the old steel plates can now be done with far greater ease. Installing new plates should be a simple reversal of process. The material to use is personal preference. Predrilling the holes for the pad eyes would be a good idea, possibly using the old plate as a template.

Use epoxy mish-mash to secure the new plates by dry fitting the pad eyes as clamps. A bit of grease on the threads will keep the epoxy from sticking to the through bolts. After the epoxy cures reinstall the pad eyes with appropriate bedding and I highly suggest that you use all new fasteners, clean-up, re-install the funiture and viola you have new backing plates.

If you opt to install external chainplates the above process is the same except that you should make the cutout deeper. This is to make it possible to add three layers of f/g to the inside of the hull where the chainplates bolt through the hull.

Now the backup plate in the bow of the 28,30 and probably 31 is a nightmare of a different flavor with no easy out. It took me many hours spread out over days to remove mine and a lot of colorful language.

The stern "Thing" was not too dificult but still a bit of a challenge. The f/g, mish mash and tight quarters made it tough to extract. On my boat it was still in v/g condition but I removed it anyway because I did not need it anymore.

Take care,
Fred

[The Patriot]

... Take care, Fred

Fred, when you get back to the States, consider this. My wife and I have a guest room with full amenities. We can put you up at no charge for 8 to 10 months. If you get bored, we can always wander down to the boat yard and mess a bit with my CD 28.

Just a thought.

[Derek Matheson]

I have stared at the CD28 chainplates on Gaelic Gal for a while now (really these are the backing plates). Thinking about replacing the rusted chainplates. Thinking about replacing with aluminum, thinking about replacing with bronze, thinking about replacing with stainless steel.

Then I thought about fiberglass. The chainplates are there to spread the load from the rigging through to the hull. Fiberglass is very stiff, doesn't rust, is cheap.

1/2" thick by 3" wide FRP (fiberglass) barstock of 6' length is available from McMaster (part number 3345K24) for $24.35. This would spread the load nicely, and I can epoxy in place, and cost about $2.03 each for a length of 6". Clearly, more is involved, like a stack of washers, access plates, etc.

I will share results if I ever get around to this.

[fenixrises]

Thanks for the gracious invite.

As a matter of fact when I return to the US, about a year and a half from now, I will probably go to that area. My family lives just north of Philadelphia.

And wait 'till you see my current project. Pics and details to follow, when the job is complete.

Take care,
Fred

[Carter Brey]

I have stared at the CD28 chainplates on Gaelic Gal for a while now (really these are the backing plates). Thinking about replacing the rusted chainplates. Thinking about replacing with aluminum, thinking about replacing with bronze, thinking about replacing with stainless steel.

Then I thought about fiberglass. The chainplates are there to spread the load from the rigging through to the hull. Fiberglass is very stiff, doesn't rust, is cheap.

1/2" thick by 3" wide FRP (fiberglass) barstock of 6' length is available from McMaster (part number 3345K24) for $24.35. This would spread the load nicely, and I can epoxy in place, and cost about $2.03 each for a length of 6". Clearly, more is involved, like a stack of washers, access plates, etc.

I will share results if I ever get around to this.

Derek,

I used this material (3/8" FRP) as backing plates for the lifeline stanchion bases on my CD25; I think it would work great for the shrouds as well:

[img]http://pws.prserv.net/cbrey/6-8-040002.jpeg[/img]

Cheers,

Carter Brey

[Sea Hunt]

Carter:

I don't know for sure, but that looks an awful lot like duct tape to me

Just kidding.

I buy duct tape by the case Don't ask why. Just know that it provides temporary repairs to a lot of "oops" jobs.

I am not sure what is more difficult. Learning how to post pictures or actually taking some of the incredible pictures that are posted on this board.

[Russell]

Interesting to hear the responses on this subject. I have actually tried my darndest to inspect my chainplates(backing plates) but cannot see them well enough. I have to use a small mirror and flash light to get behind the wire conduit which blocks my view and I really cant see well. Greg, your CD being an older vintage perhaps does not have this conduit? All my thru deck fittings along the hull deck joint are blocked by this even after removing the finishing trim. Its part of the liner so cannot be removed without literally cutting it away. I think I am pretty much stuck with the fact that I need to cut, fortunately my fein saw fits into lockers well and cuts this pretty easily, I just hate to do it, but seems nessisary.

I am actually of freds line of thought and have been for awhile now. the CD chainplate system is a bit odd, and I would feel much more comfortable with traditional chainplates. But thats why I asked this question in this thread about failures, thinking perhaps I was overly concerned and its not a problem. But reguardless of what I hear, I suspect if I find my chainplate system in need of major repair then I will be changing to external. And for what its worth, I dont think it spoils the looks, in fact I think it makes the boat even more traditional and salty looking, and a lot of peace of mind to boot. Last year I examined this whole idea and found that for the most part I just need to remove the ash strips that line the hull to do this job, I dont think much furnature disasmbly is required (knocking hard on wood here, as I realize likely its going to be harder then I think). But if after cutting away that conduit I find the chainplates are in good shape, then I will leave things be until I do find a problem.

[The Patriot]

Thanks for the gracious invite.

As a matter of fact when I return to the US, about a year and a half from now, I will probably go to that area. My family lives just north of Philadelphia. ... Take care, Fred

You may be interested to know that CD 28 # 181 was owned for quite some time by a close friend of mine who is now in Florida on a Bristol 40. I lived through many of the modifications that you discovered when you rebuilt most of her systems and structure. For example, Bob added the fireplace, the cockpit table fittings, and the seat back modifications. He also cut out the interior joinery in way of the galley to get better engine access.

I can't recall all the work, but I remember when we modified the coolant feeds to the MD7A so we could sail all winter on Barnegat Bay. After returning to the yard following some frostbiting, we'd just turn a valve to flush the raw water side with antifreeze. I think he put an Origo in there also. Many times Bob would remove teak parts from the deck (rails, cockpit coamings, etc.) for the winter and carefully refinish them at home. He always had the boat finished bright and Bristol fashion.

Further I think I know why you encountered a de-laminated bulkhead in way of the old galley location aft on the port side. When Bob bought the boat she was blocked and the port aft jackstand was essentially causing a large "dimple" about 1 inch or so deep. She had been blocked incorrectly and Bob never made the repair. Some minor modifications included changing over from blue to brown for the bottom, getting rid of the old blue decks and adding some sort of tan non-skid panels to the deck, adding tons of 5200 beading to the toe rails and rub rail, adding the bronze rub strake, etc. There were quite a few more items that escape me just now.

Needless to say, she is a completely different and amazing yacht now. If and when you do get back to the northeast I hope I get a chance to tour the "new and improved" CD 28 # 181. Congratulations, Fred.

[Carter Brey]

Carter:

I don't know for sure, but that looks an awful lot like duct tape to me

Just kidding.

I buy duct tape by the case Don't ask why. Just know that it provides temporary repairs to a lot of "oops" jobs.

I am not sure what is more difficult. Learning how to post pictures or actually taking some of the incredible pictures that are posted on this board.

That's genuine Cape Dory factory-installed duct tape! I have no idea why they put it there, under the chainplate bolts, but I certainly did not want to sunder that which East Taunton had joined.

Cheers,
Carter