I need to re-bed a chainplate and am wondering what others preferences are with regard to either silicone or polysulfide. And if you have a preference, why? Thanks John
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They will probably leak again.
John: I suggest that you look at using Life Caulk, 4200 or one of the similar products from Sikaflex. Another product that is worth looking at is Buytl Tape. This is commonly used on windows in the auto business or RV business. You can purchase a roll of the tape (looks like putty) from an RV store or home improvement center.
John: I suggest that you look at using Life Caulk, 4200 or one of the similar products from Sikaflex. Another product that is worth looking at is Buytl Tape. This is commonly used on windows in the auto business or RV business. You can purchase a roll of the tape (looks like putty) from an RV store or home improvement center.
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Jack Tyler
John, here are some suggestions...
John, I don't see this the same way Steve does and would suggest the following: 1. When's the last time you inspected this chainplate? If it's been leaking, it's quite possible that by now the plate has suffered from some crevice corrosion - which can be found right in the deck/plate interface, an area you are unable to inspect without pulling the plate. Consider doing this. You'll get both peace of mind and a chance to do a 'real' sealing job on the plate. 2. I recommend using 5200. It's flexible but within limits, will hold up well over the long period despite temp/salinity/UV/moisture assaults. But this presumes a proper rebedding. 3. It sounds like your plate penetrates the deck thru a slot and is attached below decks to some part of the hull structure. This is a tough arrangement to seal because a) you're asking a bedding agent to hold in a very narrow vertical area between plate and slot edge while presenting lots of movement within this slot due to the rig working. To put the odds more in your favor, you need to increase the cross-section of the joint (where the bedding is located). Forespar makes chain plate covers with recessed areas around the slot for this reason. However, you can accomplish the same thing when pulling the plate by simply beveling the slot opening on the deck side, thereby providing room for a lot more bedding compound to accummulate before clamping down the plate. 4. Pulling the plate, cleaning it (3M scrubby & metal polish) and carefully inspecting it will provide you with complete peace of mind and a chance to properly reinstall the plate, fully bedded in place. Jack
John, I don't see this the same way Steve does and would suggest the following: 1. When's the last time you inspected this chainplate? If it's been leaking, it's quite possible that by now the plate has suffered from some crevice corrosion - which can be found right in the deck/plate interface, an area you are unable to inspect without pulling the plate. Consider doing this. You'll get both peace of mind and a chance to do a 'real' sealing job on the plate. 2. I recommend using 5200. It's flexible but within limits, will hold up well over the long period despite temp/salinity/UV/moisture assaults. But this presumes a proper rebedding. 3. It sounds like your plate penetrates the deck thru a slot and is attached below decks to some part of the hull structure. This is a tough arrangement to seal because a) you're asking a bedding agent to hold in a very narrow vertical area between plate and slot edge while presenting lots of movement within this slot due to the rig working. To put the odds more in your favor, you need to increase the cross-section of the joint (where the bedding is located). Forespar makes chain plate covers with recessed areas around the slot for this reason. However, you can accomplish the same thing when pulling the plate by simply beveling the slot opening on the deck side, thereby providing room for a lot more bedding compound to accummulate before clamping down the plate. 4. Pulling the plate, cleaning it (3M scrubby & metal polish) and carefully inspecting it will provide you with complete peace of mind and a chance to properly reinstall the plate, fully bedded in place. Jack
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John J
Thanks Jack
The rest of the story is..... This is a 310 hull #23 and less than 3 years old. The starboard main upper chain plate leaked when we took delivery, and I suspect the dealer did a poor job of resealing it. ( lets not all act to surprised here) When on the boat last weekend we saw some water marks on the bulkhead, so I know it is leaking. I will do the chainplate first, then some sanding and refinishing of the bulkhead later. You are correct that the plate is slotted where the shroud goes through. This is why I was thinking of Polysulfide, because it remains fairly pliable over time and may flex more as the shroud flexes. I Had not looked at using the 5200 as it is a permanent adhesive, and I may have to remove the plate sometime in the future. Thanks again John
The rest of the story is..... This is a 310 hull #23 and less than 3 years old. The starboard main upper chain plate leaked when we took delivery, and I suspect the dealer did a poor job of resealing it. ( lets not all act to surprised here) When on the boat last weekend we saw some water marks on the bulkhead, so I know it is leaking. I will do the chainplate first, then some sanding and refinishing of the bulkhead later. You are correct that the plate is slotted where the shroud goes through. This is why I was thinking of Polysulfide, because it remains fairly pliable over time and may flex more as the shroud flexes. I Had not looked at using the 5200 as it is a permanent adhesive, and I may have to remove the plate sometime in the future. Thanks again John
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Vic
Another vote for 4200 and against 5200 ....
Even though the 310 is well built ... still enough flex to pull away from the 5200 bond and releak. Maybe the shock of an unexpected gibe? and then to have to clean out the 5200 ... use a dremel and play dentist? Vic
Even though the 310 is well built ... still enough flex to pull away from the 5200 bond and releak. Maybe the shock of an unexpected gibe? and then to have to clean out the 5200 ... use a dremel and play dentist? Vic
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Rodd C.
Don't use 4200 or 5200!!!
I can't beleive people have been tricked into beleiving 4200 is easier to get off. I took a large chunk of gel coat off while removing something I had bedded with 4200. I recommend 3M 101 Polysulfide. It remains flexible and holds up to UV far better than the Boat Life producs! I did the chainplates on my 36 with 4200 and got half a season out of it! Very tough to remove and clean up. I rebeded with 101 and it is still dry a two seasons later..Just my .02! 5200 Sucks you might as well fiberglass your stuff on!!!!! Rodd C.
I can't beleive people have been tricked into beleiving 4200 is easier to get off. I took a large chunk of gel coat off while removing something I had bedded with 4200. I recommend 3M 101 Polysulfide. It remains flexible and holds up to UV far better than the Boat Life producs! I did the chainplates on my 36 with 4200 and got half a season out of it! Very tough to remove and clean up. I rebeded with 101 and it is still dry a two seasons later..Just my .02! 5200 Sucks you might as well fiberglass your stuff on!!!!! Rodd C.
NO to 4200 or 5200!!
I was told chainplates should be rebedded every couple of years because they move quite a bit as the rig works. LifeCaulk or another polysulfide is best here. If done right, recaulking is simply a matter of lifting the cover (aka "beauty plate"), tape it to the turnbuckle so it stays up, remove the old caulk, mask the deck and recaulk. Four plates should take an afternoon. 4200 and 5200 are permanent and virtually impossible to remove once the seal is lost (and you will lose it). Peter H23 "Raven"
I was told chainplates should be rebedded every couple of years because they move quite a bit as the rig works. LifeCaulk or another polysulfide is best here. If done right, recaulking is simply a matter of lifting the cover (aka "beauty plate"), tape it to the turnbuckle so it stays up, remove the old caulk, mask the deck and recaulk. Four plates should take an afternoon. 4200 and 5200 are permanent and virtually impossible to remove once the seal is lost (and you will lose it). Peter H23 "Raven"
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Jack Tyler
This advice misses several points...
First, it's not surprising that folks report failed bonds when 'pulling the plate, scraping out the old stuff and replacing it with new stuff'. The issue is most likely not the choice of bedding compound but rather the engineering presented by the chain/slot interface, coupled with the denial of the owner to change the situation. Second, I don't see any acknowledgement about the 5200 release agent now available. It is not the devil it used to be when removal is required. Third, it's not surprising that some folks (most folks!) believe it's normal to rebed the plates every year or two...but then only pull up the plates to rebed them. I'm wondering how many of those plates are suffering from crevice corrosion? The reason plates are rebed is usually because of leaks below decks; that's a clear signal that crevice corrosion can and perhaps does exist. U/V damage of 3M products needs to be considered; I've coated my 5200 with paint (not as bad as it sounds, but it was two more steps: mask, then paint with an artist's brush) for this reason. It's not by chance that Forespar makes cover plates with raised recesses so that add'l bonding area is possible. Beveling the slot's edges will accomplish the same thing but isn't nearly as attractive since most folks don't want to bother pulling their plates...at least, until one breaks. Come on, folks...if you're rebedding your plates every year or two, isn't it worth peace of mind to pull at least ONE plate which has been chronically leaking? Jack
First, it's not surprising that folks report failed bonds when 'pulling the plate, scraping out the old stuff and replacing it with new stuff'. The issue is most likely not the choice of bedding compound but rather the engineering presented by the chain/slot interface, coupled with the denial of the owner to change the situation. Second, I don't see any acknowledgement about the 5200 release agent now available. It is not the devil it used to be when removal is required. Third, it's not surprising that some folks (most folks!) believe it's normal to rebed the plates every year or two...but then only pull up the plates to rebed them. I'm wondering how many of those plates are suffering from crevice corrosion? The reason plates are rebed is usually because of leaks below decks; that's a clear signal that crevice corrosion can and perhaps does exist. U/V damage of 3M products needs to be considered; I've coated my 5200 with paint (not as bad as it sounds, but it was two more steps: mask, then paint with an artist's brush) for this reason. It's not by chance that Forespar makes cover plates with raised recesses so that add'l bonding area is possible. Beveling the slot's edges will accomplish the same thing but isn't nearly as attractive since most folks don't want to bother pulling their plates...at least, until one breaks. Come on, folks...if you're rebedding your plates every year or two, isn't it worth peace of mind to pull at least ONE plate which has been chronically leaking? Jack
Rebedding plates - for Jack
For me, rebedding the chainplates is routine maintenance, not a repair. When I pull the old caulk out, it is still in good condition and the chainplate seal is still watertight. I also use this opportunity to check for leaks. Both the gap in the deck where the chainplate goes through and the underside of the beauty plate are caulked. Usually I just replace the caulk under the beauty plate. The previous owner of my boat apparently didn't pay much attention to this area and I ended up having to replace a rotted bulkhead where the chainplate was bolted belowdecks. It was no fun. I'd rather caulk every other year than saw and epoxy ever again. Peter H23 "raven"
For me, rebedding the chainplates is routine maintenance, not a repair. When I pull the old caulk out, it is still in good condition and the chainplate seal is still watertight. I also use this opportunity to check for leaks. Both the gap in the deck where the chainplate goes through and the underside of the beauty plate are caulked. Usually I just replace the caulk under the beauty plate. The previous owner of my boat apparently didn't pay much attention to this area and I ended up having to replace a rotted bulkhead where the chainplate was bolted belowdecks. It was no fun. I'd rather caulk every other year than saw and epoxy ever again. Peter H23 "raven"
J
Jack Tyler
Follow-up to Peter's points...
Sounds to me like you've got a good grasp on the chainplate issue, Peter...and in a sense, were forced into it by circumstances (the gift of a rotted bulkhead passed along by the last owner). But for others, let's just be clear that "seeing" a bedded joint between the deck's slot and the chainplate (after removal of the cover plate) isn't really possible. The geometery of that joint simply doesn't allow us to know whether that joint is watertight or not. And the problem with crevice corrosion is that, by definition, water that lies alongside stainless in the absence of oxygen creates the corrosion - which is not inconsistent with having small penetration of water that reaches the plate at its deck interface but with little leakage showing up further down the plate. This is why pulling plates every X years is considered good medicine in the same respect that replacing standing rigging is - visual inspections are good interim behavior but not an absolute solution. How often? I surely don't pretend to know, but how varied the temperature swings, how often, where and in what fashion the boat is used, and the nature of the plates (316 polished? 304 rough finished?) would all be factors I'd suggest be considered. Jack
Sounds to me like you've got a good grasp on the chainplate issue, Peter...and in a sense, were forced into it by circumstances (the gift of a rotted bulkhead passed along by the last owner). But for others, let's just be clear that "seeing" a bedded joint between the deck's slot and the chainplate (after removal of the cover plate) isn't really possible. The geometery of that joint simply doesn't allow us to know whether that joint is watertight or not. And the problem with crevice corrosion is that, by definition, water that lies alongside stainless in the absence of oxygen creates the corrosion - which is not inconsistent with having small penetration of water that reaches the plate at its deck interface but with little leakage showing up further down the plate. This is why pulling plates every X years is considered good medicine in the same respect that replacing standing rigging is - visual inspections are good interim behavior but not an absolute solution. How often? I surely don't pretend to know, but how varied the temperature swings, how often, where and in what fashion the boat is used, and the nature of the plates (316 polished? 304 rough finished?) would all be factors I'd suggest be considered. Jack
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