How to fix these buried chainplates?

[Greg K]

Agree with others about replacing.

Have read nothing but praise about Pacific Seacraft build quality, so rather surprised they decided on encapsulating these chainplates into the hull during the original build. I believe I've read someplace here that Island Packet had the same practice in building some of their boats. Wonder why any builder would do that? Aside from stainless needing oxygen, it only makes the inevitable, eventual replacement so much more difficult.

[sophiedaisey]

Originally Posted by WaldPinkler

I'm trying to find out if the pacific seacraft is the same as the crealock. I mean from the outside it looks just the same.

Unfortunately I can't look at it right now. I went through with a surveyor who said they need to be inspected. I need to find a dinghy first so I can get out to the mooring.

The PSC 40 is a Crealock. I would not do anything until I talked to Thumper at the Pacific Seacraft factory. He is the go to man for all PSC. He is extremely helpful re anything you want to now about a PSC model.

Would contact him at the factory. There is also a PSC owners group on Facebook which again is totally helpful. Can also reach him by email. It will get that and post for you. Don’t do anything without talking to him.

[boatpoker]

Originally Posted by Greg K

Agree with others about replacing.

Have read nothing but praise about Pacific Seacraft build quality, so rather surprised they decided on encapsulating these chainplates into the hull during the original build. I believe I've read someplace here that Island Packet had the same practice in building some of their boats. Wonder why any builder would do that? Aside from stainless needing oxygen, it only makes the inevitable, eventual replacement so much more difficult.

Perhaps they had no one on staff with marine corrosion training.

[roverhi]

Don't think Ive ever seen as much BAD advice as on this thread.

If I'm seeing this right, the chainplates are bolted to the inside of the hull with carriage bolts from the outside. They are probably glassed over though that may just be thick paint and caulking. In any case the leaks are coming from the deck not the bolts. That is a major problem because the unexposed portion of the chainplate is starved of oxygen which is a breeding ground for crevice corrosion in the presence of water which others have mentioned. Would be willing to bet that there is crevice corrosion where the chainplates pass through the deck. Fixing the deck leaks won't do anything for the crevice corrosion that has already happened. Those chainplates need to be pulled, inspected and probably replaced if there is any sign of more than light surface corrosion. A single small corrosion pit would hide more severe corrosion under the surface and necessitate replacement of such a critical part.

If it was me would cut off the chainplates below the deck and use them as backing for external chainplates. Glass in where the chainplates pass through the deck after determining that there is no core rot in the deck. Core rot is probably not an issue as the deck should be solid glass that far outboard. You could remove the old plates and replace but you will still be fighting leaks where they pass through the deck. Not impossible to seal but always an area of concern.

All the work could be done in the water with the stick in place. Halyards substituting for shrouds will hold the mast up just fine. Might do the repairs in sequence so at least one lower or upper wire is holding up the mast while working on other shrouds but I've worked on a mast with nothing but halyards holding it up. Doing the work on the hard will be way easier especially if you'll be drilling ss from the outside of the hull.

Staining of the hull with external chainplates is more about rust from the rigging wire than the chainplates themselves. Oxalic acid solution will remove the stain with no more physical labor than brushing it on and hosing it off. Lots of experience with my Westsail 32.

[adjo]

I really dislike embedded SS chainplates. Good bronze is OK but how often do you see that being used?

Assuming the chainplates are SS the most likely damage from crevice corrosion is where they pass through the deck so an inspection of this area will give a good indication of the likelihood of significant corrosion. I've seen quite a few that have been removed and this is invariably where they have been in the worst condition.

I would drill around them from outside and then remove the loose material with a chisel. This is much less dusty than grinding inside the boat and would give useful information. Checking for cracks at this stage with a penetrant dye and a jeweler's loupe would be the way to go.

If the metal is good here it is almost certainly acceptable further down and I would seal them up again (but I'm not particularly risk averse). Don't forget that the cross section of the plate is significantly greater than the cross-section of the pin that connects it to the rigging.

An alternative solution might be to simply cut them off at deck level and bolt internal plates plates onto the embedded ones either by drilling into them and tapping in bolts or by through bolting from the outside with countersunk bolts and making good the holes through the GRP.

Given the irregular nature of the surface it would be necessary to use a high density epoxy spacer such as resin thickened with aluminium dust (though adding colloidal silica might be considered adequate as it is very tough).

As for holding up the mast while doing the job. Not a problem.

[rdowall]

Any idea what caused the dimples or bumps located between the two chain plates?

According to your Crealock 40 boat specs (Bluewater.org), your hull is cored above the water line..."Hull construction is solid and traditional. The fiberglass is hand-laid with osomsis-resisting vinylester resin with balsa coring above the waterline (and away from any through hull fittings like chainplates)". But remember that you have about 40 fasteners on your 8 chainplates. Also check for leaks at the fasteners on the rub rail.

Given the coring and the appearance that the chainplates may not have been inspected or rebedded in 40 years I would think about doing a major exploration to make sure water hasn't migrated into the hull coring, replace the fasteners and the chainplates if deemed necessary. Given the age of the boat, find a corrosion guy to inspect the chain plates.

Be sure to check the chainplates for the inner forestay running backs. Ditto the forestay, inner forestay and backstay.

My best guess is that the leaks are the result of the old caulking at the point where the chain plates exit the hull.

[jimbunyard]

Of course we can't be sure but I'm thinking that glassing-over job doesn't look much like a factory option...

[coopec43]

Normally when there is a design problem with a yacht you will see other people on different threads asking for advice on how to remedy the problem. With a quick search I haven't found anyone with a problem with the Crealock chain-plates.

As sophiedaisey said maybe contacting the Pacific Seacraft(?) is the way to go? As there appears to be a Pacific Seacraft Owners Community and a Pacific Seacraft Owners Group I'd be contacting them for advice straight from the horse's mouth. (You will only get people airing their general theoretical knowledge here unless they have been/are a Crealock owner)


From the photo I don't know that anyone can assume there is a problem. (I'd need more evidence) Cutting out one chain-plate anchor (as has been suggested) and using that as a guide as to the condition of other chain-plate anchors seems to be very sensible advice.


Here is a relevant thread
https://www.sailnet.com/threads/coat...nplates.62484/

[coopec43]

Maybe this is the way to go?

Stumble
Marine Service Provider

I will repeat this in every chainplate thread ever. Buy titanium nice, and you never have to deal with chainplates again. You could encapsulate them permanently in stagnent salt water and it wouldn't matter. For a job that is going to take a lot of man hours, the small price increase in the materials is absolutely worth it.
__________________
Greg

https://www.cruisersforum.com/forums...on-154775.html

[WaldPinkler]

Lively debate and thank you. I'm in Australia but I'll contact Pacific Seacraft tomorrow. I'll update the thread.

The boat is built in 2000. I have no idea on the history if that was repaired. It is sloppy glassing and that paint/flowcoat on the grounding wires gives the impression it may not be factory.

[Searles]

First step ,remove the mast totally ,try to undo the chain plates bolts you can find and remove totally ,I would use a sharp wood chisel to cut away the glass overlay over the chain plates ,should then be able to drive them down into the boat ,a lot of the interior glass can be removed by chiselling out ,sharpen chisel often ,looks possible to fit external chain plates,if possible use the old ones as internal doublers ,go to at least 2 by 3/8 317L or 2205 .good luck ,not cheap, but not hard .⛵️⚓️

[jimbunyard]

Well, one thing we can be sure of is that there's plenty of 'bad' advice from both the 'brush it off' side and the 'rip it all out now' crowd.

At first, and even second and third glance it looks pretty bad, but on closer inspection, a different picture is revealed.

Almost certainly the partial 'encapsulation' was added by an overly-fastidious owner. Look at the close-ups below. Also note the velcro stapled to the ribs in the original picture to hold a panel hiding those 'ugly chainplates'...

The chopped strand mat neither meets in the middle of the individual chainplates nor is it under the washers under the nuts securing the chainplates.

You can also see the bottom edge of the left hand chainplate itself.

The problem could be something as simple as some bozo using plain carbon steel washers (note the double-nutted bolt in the second picture), combined with a leaky deck, to a complete honeycombing of the chainplates by crevice-corrosion (but at this point I'm betting against that)

My guess now would be 50-50 they need to be replaced, maybe even 60-40 against.

But there's no way to make that decision without removing the ill-advised 'cosmetic improvements'.

The simplest, quickest way to achieve that would be with the sharp chisel originally advised. It will make very quick work indeed of removing even a several-layer lamination of CSM.

Only then can an informed plan of action be made...

[Searles]

To jimbunyard,pritymuch spot on ,as a person in the trade you like myself often wonder about the slap dash advise often given here ,we all con only comment on wot we can see ,plu a life time in boat and yacht building and repair ,more power to you .⛵️⚓️

[coopec43]

Originally Posted by Searles

To jimbunyard,pritymuch spot on ,as a person in the trade you like myself often wonder about the slap dash advise often given here ,we all con only comment on wot we can see ,plu a life time in boat and yacht building and repair ,more power to you .⛵️⚓️

+1 Absolutely!

If they've had to fiberglass in a chain plate they wouldn't be part of the 'rip it all out now' crowd before doing a proper assessment.

Maybe WaldPinkler could look at this thread which appears relevant.

wsmurdoch

#8 • Mar 21, 2017

You might want to open the Search This Forum box, type in chainplates, and look at some of the past Pacific Seacraft threads on the subject. Among them is http://www.sailnet.com/forums/pacifi...-followup.html

Bill Murdoch
1988 PSC 34
Irish Eye

[wsmurdoch]

Pacific Seacraft in Fullerton, CA went bankrupt in about 2007. Steve Brodie bought the company's physical assets and moved operations to Washington, North Carolina. There they both build new boats and restore older boats. I own a 1989 PSC 34 and have had excellent support from the new owners. Contact either Steve Brodie, the owner, or more to the point, Thumper Brooks, the operations manager, Monday when they open. 1-252-948-1421

I would not do anything without their advice.

Bill Murdoch