Use Spartite to seal chainplates

[CassidyNZ]

Originally Posted by SVTatia

Your post above takes care of the bolts holding down the cover right?
I am concerned with gap around the chainplate itself.

My question exactly. My chain plate covers are identical to the OP’s except on GRP deck, not teak and keeping them water-tight is an on-going saga. So to the question.

Exactly how do you cut/form/place the butyl around the chain plate to stop water migrating down the blade? I get completely how you do the screws, forming an O-ring under the plate but that’s because the plate fully covers the screw hole. Will wrapping the butyl around the chain plate have the same effect since there is nothing pressing on the butyl where it faces onto the chain plate.

Wow, describing this is harder than I expected.

I guess what I’m saying is that in order to be watertight there needs to be positive pressure between the butyl and the chain plate blade (laterally). How is this created?

I know from own experience that Sikaflex is not a long-term solution. Geez, I really wish I could find one.

[badadim]

Originally Posted by CassidyNZ

My question exactly. My chain plate covers are identical to the OP’s except on GRP deck, not teak and keeping them water-tight is an on-going saga. So to the question.

Exactly how do you cut/form/place the butyl around the chain plate to stop water migrating down the blade? I get completely how you do the screws, forming an O-ring under the plate but that’s because the plate fully covers the screw hole. Will wrapping the butyl around the chain plate have the same effect since there is nothing pressing on the butyl where it faces onto the chain plate.

Wow, describing this is harder than I expected.

I guess what I’m saying is that in order to be watertight there needs to be positive pressure between the butyl and the chain plate blade (laterally). How is this created?

I know from own experience that Sikaflex is not a long-term solution. Geez, I really wish I could find one.

So... Spartite???

[CassidyNZ]

Originally Posted by badadim

So... Spartite???

I don’t know much about Spartite except to say that elsewhere in this thread it was mentioned that in its pre-set form it is runny and has to be supported from under the decks to prevent slumping. On my boat that is a significant challenge.

But thanks for the suggestion.

[badadim]

Originally Posted by CassidyNZ

I don’t know much about Spartite except to say that elsewhere in this thread it was mentioned that in its pre-set form it is runny and has to be supported from under the decks to prevent slumping. On my boat that is a significant challenge.

But thanks for the suggestion.

Yes, you are right - I used it for the mast (the original post on the very top shows the outcome). I understand that it was never used before to seal the chainplates. Trying to find out why not to do it?


Cons: more work and requires access from underneath, will be very hard to remove later on when chain plates must go out.


Pros: once it is cured it is there forever, it is runny and very liquid initially before it cures, so it will get into the smallest cavity and will seal it very well.


Will it cause corrosion of the chainplates? Will it survive the stress (I guess yes)?


I've contacted Sika - let's see what they come back with... TBC

[MJH]

Originally Posted by badadim

I used Sikaflex-292i to seal chainplaits covers. It lasted only for 2 years when I was expecting up to 5. Well, not all of the covers are leaking but one started to leak.

- is it unrealistic to expect covers not to leak for 5 years?
- should I re-seal the covers annually?
- what is the best sealant to use and was Sikaflex-292i right choice?
- timeframe for Sikaflex vs 3M vs butyl tape?
- will it be dumb to fill the gap between the chain plates and the hull with Spartite before applying any sealant under the covers?

I am very happy with Spartite on the mast - no leaks for 5 years now. Will it work on the chainplates?

Thank you!

A surveyor once told me to use 3M 5000 for chainplates but to put a new tube into hot water first so that it would run thinner and fill all the voids. But Practical Sailor says not to use it as it does not adhere well to stainless steel.

Has anyone on this forum used Silaprene made by Uniroyal. I read one very positive report where the owner used Silaprene #M6324 because it had better adhesion to stainless steel than 3M 5200 and also a wider operating temperature range. Does that mean it will be even more difficult to remove if you have to rebed again or that one bedding lasts a lifetime?

There are ads for Silaprene #M6325 on the web but I don't see any for #M6324.

~ ~ _/) ~ ~ MJH

[SVTatia]

Originally Posted by badadim

Yes, you are right - I used it for the mast (the original post on the very top shows the outcome). I understand that it was never used before to seal the chainplates. Trying to find out why not to do it?


Cons: more work and requires access from underneath, will be very hard to remove later on when chain plates must go out.


Pros: once it is cured it is there forever, it is runny and very liquid initially before it cures, so it will get into the smallest cavity and will seal it very well.


Will it cause corrosion of the chainplates? Will it survive the stress (I guess yes)?


I've contacted Sika - let's see what they come back with... TBC

My boats had deck-stepped masts so I've never heard of Spartite. I checked the Youtube video below, it is not that liquid... you could even skip the foam and just place the play-dough supported by masking tape from underneath to form the dam (assuming you have access). Not sure how permanent Spartite is though.
You really don't need it to adhere well to SS, if its good enough for aluminum I guess it would be good for SS. The top plate could be installed with butyl as I mentioned, further waterproofing the chainplate.

But is Spartite overkill? At $150 its steep! Irrespective of the price, I think Sika 291 covered by butyl would do just as good.

https://www.youtube.com/watch?v=PTakwY3JcY8

[sailcrazy]

We followed an old riggers advice when we redid our rig in 2011. We do have a teaK deck. I unscrewed the chainplate deck cover and raised it as much as I could along the chainplate. Then took a narrow wood chisel and cut the teak deck around each chainplate, then cut/chipped thru the teak deck and the f/g deck so I had a ~60* sloping opening from the deck down to the bottom of the deckplate. Then I filled/stuffed Butyl into that gap, lowered the chainplate deck cover and screwed it down, and removed the excess that squeezed out. Even today the Butyl remains pliable enough to move with the chainplate, doesn't crack or pull away, and totally stops any water ingress. It's been good now for nearly 10 years-with no water leaks along the chainplates. PS...we used West Marine Butyl...it was all we could get at the time-maybe not the best, but can't be all bad!

[SVTatia]

Originally Posted by sailcrazy

We followed an old riggers advice when we redid our rig in 2011. We do have a teaK deck. I unscrewed the chainplate deck cover and raised it as much as I could along the chainplate. Then took a narrow wood chisel and cut the teak deck around each chainplate, then cut/chipped thru the teak deck and the f/g deck so I had a ~60* sloping opening from the deck down to the bottom of the deckplate. Then I filled/stuffed Butyl into that gap, lowered the chainplate deck cover and screwed it down, and removed the excess that squeezed out. Even today the Butyl remains pliable enough to move with the chainplate, doesn't crack or pull away, and totally stops any water ingress. It's been good now for nearly 10 years-with no water leaks along the chainplates. PS...we used West Marine Butyl...it was all we could get at the time-maybe not the best, but can't be all bad!

Like this?

[sailcrazy]

SVTatia....yes, except I didn't use asny sealant on top of the Butyl. I just worked the butyl into the exposed area-all around the chainplate, then pushed the coverplate into it to further compact it, and then screwed the coverplate down. Cleaned up the excess, and nothing more. The butyl is still malleable, and continues to seal out the water as the chainplate moves around as the loading changes. I should note that I used 5200 before, and it sealed just fine....until the chainplate moved, the seal cracked, and it leaked! For a long time before I figured it out!

[sailcrazy]

I should also add that I used the same butyl to install and reseal both our flush-mounted deck glass prisms....and neither has leaked since!

[badadim]

Originally Posted by sailcrazy

I should also add that I used the same butyl to install and reseal both our flush-mounted deck glass prisms....and neither has leaked since!

Oh! Glass deck prisms is my favorit topic! A friend of my just took them out and fiberglassed it after many years of messing with it. I have two of those prisms on starboard. The forward one is too close to the chainplates and shrouds, I suspect that area of the deck is moving, not a lot but even slight constant movement results in that prism leaking sooner. I tried many different sealants, many of which provided "guarantee". The last one was Sikaflex something and it leaked. After talking to Sika, I followed their protocol with the primer and activator and for now no leaks for about 2 years. Quite a progress for me.