Chain plate or impact.
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I do know that Seafever pounded on some piles hard enough at some point in in its past when its mooring chain failed and broke open most of the starboard side of the boat
There was not really much obvious external damage as the rubber rub rail hid it very well
It was not obvious how bad it was unit I stared re-coring the foredeck section of the hull and I was able to lift the deck by hand
There was not really much obvious external damage as the rubber rub rail hid it very well
It was not obvious how bad it was unit I stared re-coring the foredeck section of the hull and I was able to lift the deck by hand
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Friend of mine with a lot more experience than me took a look over the week end and proclaimed it impact, minor and I was a wuss (I stopped all sailing in mid-august when I found it).
I'm waiting for the thermal imaging - should be Wednesday.
I'm waiting for the thermal imaging - should be Wednesday.
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The survey is done, I don't have the report yet so I can't share the images.
Per the verbal report all my chain plates show signs of moisture intrusion - and we found additional spider cracking (less obvious) at other plates - some in the white gel below the cove stripe (blue).
The only good, dry plate is the forestay.
I reckon I'll be in the vendor tents at the boat show, talking to riggers
At this point I'm not sure if I'll be going at them from the inside or the outside.
Per the verbal report all my chain plates show signs of moisture intrusion - and we found additional spider cracking (less obvious) at other plates - some in the white gel below the cove stripe (blue).
The only good, dry plate is the forestay.
I reckon I'll be in the vendor tents at the boat show, talking to riggers
At this point I'm not sure if I'll be going at them from the inside or the outside.
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Jim,
I saw no images that indicated a major imminent collapse or disjointed chain plate.
I'm perhaps operating under an abundance of caution, but I always handle safety issues that way.
I have no training in thermal image reading (and I didn't stay at a Holiday Inn Express), but I do have a minor bit of metallurgic training including NDI from my days as a USAF Metals Processing Specialist in my early 20's. I think by the time a thermal image would show a break I'd be picking up mast pieces.
With encapsulated plates it's not like a weak spot can develop and part of the plate pull upwards, the entire surface area of the plate is essentially glued to the hull.
The good, and confusing news is that other than gel coat cracking - there is no sign of movement or delamination.
Obviously I'm continuing to educate myself on this.
I saw no images that indicated a major imminent collapse or disjointed chain plate.
I'm perhaps operating under an abundance of caution, but I always handle safety issues that way.
I have no training in thermal image reading (and I didn't stay at a Holiday Inn Express), but I do have a minor bit of metallurgic training including NDI from my days as a USAF Metals Processing Specialist in my early 20's. I think by the time a thermal image would show a break I'd be picking up mast pieces.
With encapsulated plates it's not like a weak spot can develop and part of the plate pull upwards, the entire surface area of the plate is essentially glued to the hull.
The good, and confusing news is that other than gel coat cracking - there is no sign of movement or delamination.
Obviously I'm continuing to educate myself on this.
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Chuck,
As you are aware, I'm new to all of this, so please forgive any naievity in my questions. I understand that there is some water in that area, that make sense to me. All boats leak, you're going to see water around the chainplates. How far away, how much, etc., is another story, but I find it hard to believe that any boat will be perfectly dry, especially around an area like that that is subject to dynamic loads. The deck penetration is a weird shape and it's got to be tough to keep that properly sealed (not that you shouldn't try!).
But what I don't get is how the surveyor connects the moisture at the deck to the problem you showed in the picture. If it was winter, I could understand that water got into the area, froze, and then created the cracks you saw. Obviously, that's not the case. Is the surveyor saying that the water also penetrated deep enough that it weakened the chainplate/hull joint so that the forces were concentrated on a small portion of the chainplate? If so, is that cracking near the bottom of the chainplate?
Sorry, I don't mean to dwell on this, just trying to learn.
As you are aware, I'm new to all of this, so please forgive any naievity in my questions. I understand that there is some water in that area, that make sense to me. All boats leak, you're going to see water around the chainplates. How far away, how much, etc., is another story, but I find it hard to believe that any boat will be perfectly dry, especially around an area like that that is subject to dynamic loads. The deck penetration is a weird shape and it's got to be tough to keep that properly sealed (not that you shouldn't try!).
But what I don't get is how the surveyor connects the moisture at the deck to the problem you showed in the picture. If it was winter, I could understand that water got into the area, froze, and then created the cracks you saw. Obviously, that's not the case. Is the surveyor saying that the water also penetrated deep enough that it weakened the chainplate/hull joint so that the forces were concentrated on a small portion of the chainplate? If so, is that cracking near the bottom of the chainplate?
Sorry, I don't mean to dwell on this, just trying to learn.
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I honestly don't have an answer at this point Jim.
I know (and knew when I bought it) that at some point there was a leak in the area of one plate.
Like you I know all boats leak, somewhere, sometime.
I can understand water leaking around a chain plate's cover and corroding the top couple of inches of my cap plate (teak) and bulwark (4-6 inches high in that area - and that's before it gets to the 'hull' or the deck level.
How is would continue down the encapsulated - which I take to mean solid fiberglass and resin wrapped plate and then delaminate of cause movement enough to crack gell coat - I'm thinking that's rocket science and only a grinder can tell.
Unfortunately, but the time I have it ground out to see if there's a problem, well it will need to be replaced won't it.
I know (and knew when I bought it) that at some point there was a leak in the area of one plate.
Like you I know all boats leak, somewhere, sometime.
I can understand water leaking around a chain plate's cover and corroding the top couple of inches of my cap plate (teak) and bulwark (4-6 inches high in that area - and that's before it gets to the 'hull' or the deck level.
How is would continue down the encapsulated - which I take to mean solid fiberglass and resin wrapped plate and then delaminate of cause movement enough to crack gell coat - I'm thinking that's rocket science and only a grinder can tell.
Unfortunately, but the time I have it ground out to see if there's a problem, well it will need to be replaced won't it.
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Take them out from the inside - don't even THINK about going through the outside. Remove them intact and take them to a machine shop that does stainless - they can simply cut new ones from bar stock and use yours as a template for any drilling.
Sand and polish the new ones then get them electropolished - they will outlast you.
The simplest install would be to drill through from outside the hull and mount them in their original places inside the hull (after grinding those areas smooth).
Sand and polish the new ones then get them electropolished - they will outlast you.
The simplest install would be to drill through from outside the hull and mount them in their original places inside the hull (after grinding those areas smooth).
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The plate is not totally encapsulated. It protrudes where the rigging attaches. Stainless expands and contracts at a different rate than fiberglass. There is not a way to permanently seal this with fiberglass. Same issue occurs with rudderposts made of stainless inside fiberglass rudders - they all get wet eventually.
In my opinion that is the worst way to attach chainplates - at least for whoever owns the boat after a few decades.
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Chuckles, there is a lot to recommend putting them on the outside of the hull where they can be easily inspected. In your case, you won't lose any sheeting angle as the chain plates are not going to move very far outboard, if at all. You can have them manufactured out of beefy flat bar and make matching backing plates to take the load. If you bed them with butyl (on the outside plates only), you'll never have another leak.The survey is done, I don't have the report yet so I can't share the images.
Per the verbal report all my chain plates show signs of moisture intrusion - and we found additional spider cracking (less obvious) at other plates - some in the white gel below the cove stripe (blue).
The only good, dry plate is the forestay.
I reckon I'll be in the vendor tents at the boat show, talking to riggers
At this point I'm not sure if I'll be going at them from the inside or the outside.
If you haven't already cut everything open, how about just cutting plates off under the deck and remove the bit that sticks thru the deck .Glass the opening and use the remaining plate as backing for new plates on the outside of hull. Drill thru from outside and bolt it all together.
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I think it would be worth it to remove the plates from inside the hull and mount backing plates on the inside where you can see them. Metal plates embedded inside the hull will eventually cause problems as they expand and contract at different rates. Digging them out and reglassing isn't such a big job.
Interesting thread - I've learned quite a bit from reading it.
To the guys who say things like 'removing the plates and re-glassing aren't such a big job'...I don't think that's the case for everybody.
I've done a fair amount (altho much less than most on this forum, to be sure) of repair work, involving some glass, lots of resin; sheathed a wooden boat in glass, etc..., but I find that significant glass work like this always makes me nervous, especially when it's structural in nature...How many other guys feel like that??
On a side note - Chuckles - in the original picture, are you actually standing in your dinghy, in the water, with an extension cord hanging over the side of the dinghy while operating a power tool???
I hope this is an optical illusion, and there are some safety precautions that I don't see in the picture, or I suspect self-electrocution is a much larger worry for you than a dismasting.
To the guys who say things like 'removing the plates and re-glassing aren't such a big job'...I don't think that's the case for everybody.
I've done a fair amount (altho much less than most on this forum, to be sure) of repair work, involving some glass, lots of resin; sheathed a wooden boat in glass, etc..., but I find that significant glass work like this always makes me nervous, especially when it's structural in nature...How many other guys feel like that??
On a side note - Chuckles - in the original picture, are you actually standing in your dinghy, in the water, with an extension cord hanging over the side of the dinghy while operating a power tool???
I hope this is an optical illusion, and there are some safety precautions that I don't see in the picture, or I suspect self-electrocution is a much larger worry for you than a dismasting.
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Glass work is what is referred to as "semi-skilled labour". Most boats other than high tech ones are laid up by low paid workers. It takes very little experience to get quite good at it. Experience mostly makes your work neater, not stronger.
Cutting out those chains would be nasty work due to all the cutting & grinding it would require but it wouldn't require a lot of skill. Having a second person holding a powerful vacuum next to the tool would help a LOT.
That's assuming they aren't also buried behind cabinetry - removing that without damaging it would require some finesse.
People who haven't done glass work are often intimidated by it but if you can wallpaper you can laminate glass. I find it easier than papering actually because you don't have to be so precise - the seams don't have to be perfectly aligned.
Cutting out those chains would be nasty work due to all the cutting & grinding it would require but it wouldn't require a lot of skill. Having a second person holding a powerful vacuum next to the tool would help a LOT.
That's assuming they aren't also buried behind cabinetry - removing that without damaging it would require some finesse.
People who haven't done glass work are often intimidated by it but if you can wallpaper you can laminate glass. I find it easier than papering actually because you don't have to be so precise - the seams don't have to be perfectly aligned.
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Alright folks.
Here are the images I got back.
This is an image taken from the outside.
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The red is a fixed window, the purple going through it is the chain plate - not yet going through the deck.
The arrows are highlighting areas that show moisture. There is literally no way to tell is there is corrosion or not. The curving line is my jib sheet and the horizontal band is my toe rail (a 2x3 inch teak rail).
Go back to my first post in this thread - the bottom arrow points to the spider crack
The yellow line is a bookcase shelf, the lighter vertical band is a chainplate, the arrows point to water/moisture. Note the moisture is to aft of the plate - gravity would take it that way.
Earlier in the thread there is a photo showing this area - the water damage lines up with the moisture area.
Directly underneath the above photo - surprise, I have two drips (it was raining the day before. This is on the side as in 'wipe with finger' water, not inside.
For all I know all the moisture is inside, not internal. I'll know more once I de-construct the furniture.
That will be a new thread, I'll stick a link to it in this thread.
Here are the images I got back.
This is an image taken from the outside.
The red is a fixed window, the purple going through it is the chain plate - not yet going through the deck.
The arrows are highlighting areas that show moisture. There is literally no way to tell is there is corrosion or not. The curving line is my jib sheet and the horizontal band is my toe rail (a 2x3 inch teak rail).
Go back to my first post in this thread - the bottom arrow points to the spider crack
The yellow line is a bookcase shelf, the lighter vertical band is a chainplate, the arrows point to water/moisture. Note the moisture is to aft of the plate - gravity would take it that way.
Earlier in the thread there is a photo showing this area - the water damage lines up with the moisture area.
Directly underneath the above photo - surprise, I have two drips (it was raining the day before. This is on the side as in 'wipe with finger' water, not inside.
For all I know all the moisture is inside, not internal. I'll know more once I de-construct the furniture.
That will be a new thread, I'll stick a link to it in this thread.
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The chainplates are probably fine, but this just isn't something that you leave as a question mark hanging over your head.
I'm sorry that you have to go through all this work, but at least it's near the end of the season, and you can spend the winter working on it.
I'm sorry that you have to go through all this work, but at least it's near the end of the season, and you can spend the winter working on it.
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Here's the follow on thread:
http://www.sailnet.com/forums/gear-...hain-plate-maint-replacement.html#post1105689
http://www.sailnet.com/forums/gear-...hain-plate-maint-replacement.html#post1105689
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