How to fix these buried chainplates?

[Manateeman]

Manatee crew advice. Pull mast. Cost, X dollars. Reason... If chainplates looked bad, who knows what’s going on where rigging meets mast or at spreaders. Has manatee crew ever seen keel step mast fold at spreaders...yes. Cost, X+.
Grind glass inside boat. Spend Y dollars for plastic, tape, tyvek suits, blower filters, mask. Manatee crew still finds minute amounts of dust everywhere. They take nasal swabs to friends lab. Doctor prescribes further pulmonary testing. Also lectures them on lung tissue damage. Cost Y+. Lecture doubles Physician fees.
Manatee crew now wearing custom tee shirts calling for the French scientist who was responsible for naming Australian Sirenia “Dugongs” to be sent to Madame Guillotine. He died long ago. No matter. His grave covered with empty beer cans and pizza boxes. Like their Elephant cousins, they never forget.
Happy trails to you.
Mark and the manatee crew.

[coopec43]

Originally Posted by Manateeman

Manatee crew advice. Pull mast. Cost, X dollars. Reason... If chainplates looked bad, who knows what’s going on where rigging meets mast or at spreaders. Has manatee crew ever seen keel step mast fold at spreaders...yes. Cost, X+.
Grind glass inside boat. Spend Y dollars for plastic, tape, tyvek suits, blower filters, mask. Manatee crew still finds minute amounts of dust everywhere. They take nasal swabs to friends lab. Doctor prescribes further pulmonary testing. Also lectures them on lung tissue damage. Cost Y+. Lecture doubles Physician fees.
Manatee crew now wearing custom tee shirts calling for the French scientist who was responsible for naming Australian Sirenia “Dugongs” to be sent to Madame Guillotine. He died long ago. No matter. His grave covered with empty beer cans and pizza boxes. Like their Elephant cousins, they never forget.
Happy trails to you.
Mark and the manatee crew.

What's the point of that cXXp! Geez!!

[alaskanviking]

Do not leave the old plates in the glass! There is very likely water around the plate. It will continue to corrode and rot, affecting the bolts. it could delaminate the glass. If it really decays over the years the voids and gaps will weaken the backing plate could allow bad things to happen.

Titanium is an option. It's come down in price. A bit more than stainless. Some boats like island packets replace glassed in chain plates and glass the new ones in. I don't feel comfortable with that, bug if it was the rout I took I would have done titanium. Stainless is actually a really bad metal for a chain plate and glasses in removes the "stainless" part of the stainless. Titanium doesn't corrode. I don't like not being able to inspect later so I switched to a bolt on setup.

Aluminum bronze is a good external plate material. Better than stainless. But even with stainless you can inspect regularly with external. For external I contacted a bronze foundry but they were too busy beyond initial communication. Copied the hull curve onto plywood but Never got a warm fuzzy about where to send in old plates, or dimensions. For easier straight chain plates bronze is easy to work and you can cut out from plate yourself, I've seen this done.

Biggest problem with external plates is you don't have a template to make new plates. The hull curves making it difficult to get your hike pattern correct. This is where it's probably best to have someone else do it, as replacing mistakes can get expensive.

If you grind out the old plates and install in the same position, use sister plates (external backing plates).

I would call both locations in advance to see if the yards there has done this kind of work. Each boat is unique and therefore the solution will be unique to your boat. I showed you pictures of what I did, that may not be the best solution for your boat. I had 3 different riggers look at it, searched forums, contacted experts over the years to get to a point where I felt I could take action. If the yard doesn't understand or hasn't dealt with this more unique issue try to find a yard that has. Call rigging shops also. Some work with this kind of chain plate conversion

Grinding fiberglass in the boat isn't a big deal. Just sheet everything off with good plastic to contain the mess. Yard workers also put down a sign board type of plastic that helped keep the interior deck nice. White heavy duty tape held everything down. Poopy suit is a must but hot. The dust is still going to get in, just accept it and the itch that comes later. Use a really good respirator and full facemask. You don't want this crap in your eyes trust me. Even then the high concentration of dust can overwealm the small area, and you have to pause to let the air clear, even with a vacuum running and fans blowing it away. I had to grind inside the cabinets so I had to grind a bit, than rest an let the vacuum clear the air then repeat. The fine dust was attracted to the face shield so I had to clean it a lot. Not fun but not hard. Cleanup after sucks also fine dust gets everywhere. Vacuum, and brush, then wrap up the plastic. Get a bucket of simple green or similar and got water and wipe down everything.

It was 14 solid hours of grinding and cutting, an beating/prying old plates out. In San Diego at $100 - $160 per hour that's $2000+ just in labour to remove old plates and at least a full day or weekend. Does not include cleanup time or the grinding the boat yard workers did to get through the core and shape the area for new glass. Better for you to grind out the plates yourself.

I didn't think about the asthetics when I started thinking about this. Its one of the better reasons to take down the mast and have the yard or rigging shop do the work, other than the "warranty" aspect. It's a lot more work than I realized to make sure everything is measured out and aligned properly. Hull is curved makes things complicated. Fiberglass likes to grab a drill bit and pull it slightly off from where you want it to cut. Keeping the drill level and square isn't nessesarily the easiest task and they yard had 2 people for this task 1 to help watch the angle of the drill.

[mcon12000]

I’ll keep it short and I’ve done this job from removal to complete fabrication of the parts from raw materials.

1. Cut them all out the problems are in areas that can’t be inspected while installed on the boat. This is true with externally mounted stainless steel plates as well.

2. Replace them all with silicon bronze, 316 Stainless or Titanium

3. Replace all the hardware do not reuse anything and you’ll realize why when the bolt heads pop off during removal.

4. Remove the mast. Not removing it in an attempt to save time is only kicking the can down the road. You’ll realize the importance of this either when you inspect it on the ground or when you’re at sea and a strange bolt or screw appears on the deck.

5. If you’re making the plates yourself and using stainless you’ll want to use annular bits on a decent drill press at the lowest speed available. The holes need to be 1/32” oversized and although you can polish them yourself it’s very time consuming. Electro polishing is the way to go.

6. Use the old plates as your drill guides. There’s really not a better approach than clamping them to the new material and using this method if you want reassembly to go smooth. The original mounting holes in the bulk heads and knees where likely drilled by hand so left and right may not be easily interchangeable but look identical.

7. Put an anti Gaul product on all the threads.

[Wolfhound]

Many old-timers liked Monel better than stainless or bronze. How it compares to titanium I don't know.

[Manateeman]

If someone asks how to do this repair, and further, asks what are the risks, do you think they are professional boatbuilders who have some idea of how to try to lower these risks ? Are you helping them with advice to go ahead and suit up for grinding inside the hull. Do they know how to do this without step by step training. Do they understand the risks?
Your lungs can’t deal with fiberglass. They cannot clear it. You risk permanent lung damage. Period.
There was a time boatbuilders believed all the filters, plastic and suits would be sufficient to protect them, but unfortunately that is not the case. Glass dust kills.
It gets stuck on everything and transfers to others through the air .
Look at asbestos, coal dust, micro plastics. You get one set of lungs. You want to risk them for a boat?
Have you ever seen someone on a ventilator? Talked to doctors about what brain damage happens...about the difficulty of getting patients off a ventilator?
I’m not going to grind fiberglass ever again and I know a lot of other boatbuilders who feel the same. You can buy the very best equipment, get the very best training on getting into and out of equipment, but in the end, the crap just gets past your best efforts and into your lungs. A boat is not a clean room. It’s impossible to remove it. It’s in every new glass boat, thankfully, most of it is stuck in place, but you can find it because it was once airborne. Boatbuilders deal with a lot of materials which can damage your lungs like aerosil and epoxy. The industry actively try’s to improve the risks but everyone knows the risk of permanent lung damage is nothing to be taken lightly.
Under no circumstances would I recommend someone who is untrained, to grind fiberglass inside a boat.
Happy trails to you
Captain Mark and his crew of professional boatbuilders.

[Clivevon]

Originally Posted by Manateeman

If someone asks how to do this repair, and further, asks what are the risks, do you think they are professional boatbuilders who have some idea of how to try to lower these risks ? Are you helping them with advice to go ahead and suit up for grinding inside the hull. Do they know how to do this without step by step training. Do they understand the risks?
Your lungs can’t deal with fiberglass. They cannot clear it. You risk permanent lung damage. Period.
There was a time boatbuilders believed all the filters, plastic and suits would be sufficient to protect them, but unfortunately that is not the case. Glass dust kills.
It gets stuck on everything and transfers to others through the air .
Look at asbestos, coal dust, micro plastics. You get one set of lungs. You want to risk them for a boat?
Have you ever seen someone on a ventilator? Talked to doctors about what brain damage happens...about the difficulty of getting patients off a ventilator?
I’m not going to grind fiberglass ever again and I know a lot of other boatbuilders who feel the same. You can buy the very best equipment, get the very best training on getting into and out of equipment, but in the end, the crap just gets past your best efforts and into your lungs. A boat is not a clean room. It’s impossible to remove it. It’s in every new glass boat, thankfully, most of it is stuck in place, but you can find it because it was once airborne. Boatbuilders deal with a lot of materials which can damage your lungs like aerosil and epoxy. The industry actively try’s to improve the risks but everyone knows the risk of permanent lung damage is nothing to be taken lightly.
Under no circumstances would I recommend someone who is untrained, to grind fiberglass inside a boat.
Happy trails to you
Captain Mark and his crew of professional boatbuilders.

I have no special knowledge on the subject but this sounds very believable & like very good advice to me. I'll be taking it anyway.

[double u]

Originally Posted by Sailmonkey

This is terrible advice!!

When stainless is encapsulated it’s unable to interact with oxygen. Once it’s gotten wet and starts bleeding rust there’s very high probability that the chain plates are done or near done.

Pumping in a brittle substance like neat resin will only exacerbate the problem. It’ll serve to further block oxygen as well as encapsulate more saltwater in with the stainless.

second that!
Italian sloop docked a few boats down from us - minus it's mast: chaniplate broken just inside the transition-point through the deck, severe crevice corrosion. stainless chainplate. nearly 3 decades ago - problem still current with stainless though.

[double u]

"...anti Gaul..." - hilarious! (what's with your francophobia? )

[Nicholson58]

Older boats with SS buried chain plates may have crevice corrosion just below the top of the deck. This is an oxygen starved, high salt zone and can form micro galvanic cells that progressively cut the plates in two. You must find a way to inspect them in full, in hand. On our 1984 Camper & Nicholson, a prime age for this, I removed the bolts, attached a halyard and a safety restraint line and jacked them until they flew out. This required some severe hammering to release the epoxy bedding. Once in hand, I polished with a D-A Orbital sander and fine paper. The cracks were plainly obvious. All four have been replaced with Gr5 titanium.

[coopec43]

Originally Posted by Fore and Aft

Jimbunyard I would say Boatpoker and myself have surveyed countless chain plates and seen the consequences of a chain plate failure on more than a few occasions. We only have one photo to go on but the OP said he got a $5000 discount because of the chain plate issue so myself and a few others cannot be the only ones thinking they should come out?
Its really an easy job once the mast is craned off and the boat interior taped up. I used to put my sperm suit on and do all the grinding and cutting in one go. Then do a meticulous vacuum and a wipe down with water to get any residual dust. Then its a matter of assessing the job in a clean environment and working out the best way forward. Any more glassing can be done in epoxy with peel ply on top to avoid the grinding issue.
I am not sure why the Dugong herd is worried about grinding inside the boat, Spongebob Squarepants can just wipe them down afterwards!
Cheers

I think this is the post I am looking for in regard to re-glassing in new chain-plates with epoxy. Up until recently I would have agreed with you but now I would certainly use polyester (or vinyl-ester) rather than epoxy to glass in chain-plates.

When I glassed in the anchors for the steering pulleys (at the quadrant) and the autohelm the resin supplier asked why I was using epoxy? He said I should be using polyester. When I thought about what he was saying it made sense.

I ground the surface of the hull and laid a square meter of glass cloth using epoxy. I should have used polyester and completed the job with polyester.

Polyester is almost as strong and about X5 times cheaper than epoxy. I find polyester easier to use anyway. This article explains the logic very succinctly.

https://www.lbifiberglass.com/about-us/


WHICH RESIN TO USE?? EPOXY vs. POLYESTER vs. VINYLESTER

• Tech Guides
• 8 Comments

More than 95% of all boats, truck & car bodies made of fiberglass are made primarily of E-glass, an orthothalic polyester resin and isothalic polyester gelcoat.
Therefore, items constructed with these materials should be repaired with the same or compatible material. LBI’s 301 orthothalic polyester resin is a good choice for most repairs. It provides a chemical bond to the existing laminate with similar strength & flexural characteristics.
Ortho polyester, isothalic polyester and vinylester resins are compatible, they all have styrene (commonly known as the “fiberglass smell”) and chemically bond to one another.
When higher strength, bond and water resistance is required (such as keel, rudder repair, or out-board transom replacement) use LBI’s 302 Isothalic Polyester Resin.
To achieve the highest bond strength and water resistance use LBI’s 901 Vinylester Resin.
Vinylester is essentially a styrene modified epoxy resin. It adds excellent strength, rigidity, adhesion, water and chemical resistance.
KEEP IN MIND

• Epoxy adheres to wood much better than polyester does. To cover wood, a laminate using epoxy resin and 10 oz, cloth will yield a much better job than 10 oz. cloth and polyester resin. The epoxy/cloth laminate is comparable to using polyester resin with 3/4 oz. mat and 10 oz. cloth however the epoxy laminate requires much less labor to fair.
• A polyester laminate job is somewhat less expensive in material costs than an epoxy laminate project of the same size.

REMEMBER

• Fiberglass mat should not be used with epoxy because the binding material in the mat will NOT dissolve in epoxy resin.
• Either mat, cloth or woven roving may be used with polyester or vinyester resin.
• Since mat sticks much better to wood than does cloth, always make mat your first layer against the wood to be covered in a polyester laminate project.
• We recommend using a layer of mat between layers of cloth for maximum adhesion between layers.

[coopec43]

Originally Posted by double u

second that!
Italian sloop docked a few boats down from us - minus it's mast: chaniplate broken just inside the transition-point through the deck, severe crevice corrosion. stainless chainplate. nearly 3 decades ago - problem still current with stainless though.

Surely that is extremely poor design for a chain-plate?

I wonder how long chain plates last in a properly designed yacht? Are there yachts that have never needed the chain-plates replaced in (say) a 40 year life?

[rossdv8]

Originally Posted by Fore and Aft

Same with yourself, suit up and mask up.
You could muck around and keep the mast up and do one side at a time. But for me the quicker the itchy work is done the better.

Something I discovered recently was 'the Cordless Stick vac'. It is far too late for me and my fibreglass sanding adventures since my last Quarter Tonner was destroyed in as cyclone (just as the previous one was ten years prior).

Obviously the suit up, mask up part is the most important, but I would have killed to have the suction, and convenience of one of these lithium jobs, especially with the long tube removed so it could vacuum exactly where I was grinding.

There might even be special versions in hardware stores, although the couple I bought recently for household use were $100 and have been copping a hiding. I've vacuumed fibreglass that I've been cutting with a diamond blade and sanding, and the hepafiltery thingy seems to work great.

I had similar looking chainplates and leaking, albeit on a smaller scale. When I investigated, the stainless plate under the fibreglass wasn't damaged in any 'obvious' way. However, removing one nut at a time, showed some nasty problems with the bolts.

Fortunately on mine, although it was a pain in the r's I could get at one bolt at a time and replace it, leaving the mast up.

Then clean grind, sand and clean up the leak area, replace what was supposed to be the Sikaflex (which didn't flex at all after 30 odd years) with the only thing I had on hand, Selleys Wet Area Silicone Bathroom Sealant.

I carried the silicone bathroom sealant because I found it can seal leaks around cabin windows 'while they are leaking'. Once you know how to build up the initial film on the wet, leaking surfaces.

I wouldn't recommend using Silicone to seal through deck fittings like chain plates though. It probably rots stainless...

The new bolts and nuts worked a treat, and although the mast was broken in half and torn down (by the vessel that dragged her off her mooring) when the boat came ashore the chainplates were still holding the mast to the boat.

Sorry if I sound angry. I'm picturing my poor little yacht lying in the mangroves and rocks.

[coopec43]

Originally Posted by Nicholson58

Older boats with SS buried chain plates may have crevice corrosion just below the top of the deck. This is an oxygen starved, high salt zone and can form micro galvanic cells that progressively cut the plates in two. You must find a way to inspect them in full, in hand. On our 1984 Camper & Nicholson, a prime age for this, I removed the bolts, attached a halyard and a safety restraint line and jacked them until they flew out. This required some severe hammering to release the epoxy bedding. Once in hand, I polished with a D-A Orbital sander and fine paper. The cracks were plainly obvious. All four have been replaced with Gr5 titanium.

Well they apparently lasted 36 years? I suspect Camper and Nicholson is a well engineered yacht but why has it been suggested chain-plates should be replaced every 10-15 years? How well are they designed?



I posted these photos earlier on of the chain-plates on the yacht I am building. How can salt water cause crevice corrosion on those chain-plates? Any sea-water getting below decks would end up on the cabin floor surely?

[Sailmonkey]

Originally Posted by coopec43

Well they apparently lasted 36 years? I suspect Camper and Nicholson is a well engineered yacht but why has it been suggested chain-plates should be replaced every 10-15 years? How well are they designed?



I posted these photos earlier on of the chain-plates on the yacht I am building. How can salt water cause crevice corrosion on those chain-plates? Any sea-water getting below decks would end up on the cabin floor surely?

Your chain plates are susceptible where the bolts penetrate the deck. I’ll wager that unless they’re pulled and re-bed every few years you’ll end up with corrosion on the bolts. They don’t need to even visibly leak for this to happen.