Chainplates with a photo

[higgs]

This photo is not the clearest, but it shows the problem. There is no way to lift the cover up high enough to ensure that the slots for the plates are properly filled with sealant. When the chain plates are completely removed there is good access to the slots, but when pushing the plates back into place, the sealant is disturbed and, because the cover has to be installed at the same time, there is no way to be sure the slots are properly filled.

I only see two options. Either cut the cover so it can be put on in pieces or cut off the spacers that are welded to the chain plate.

 

[Eric M]

Looking at your photo, the spacers are in the load path of the rigging, the cover is not, so if I had to make the choice, it would be the cover to be modified. If you are going to the trouble to completely remove the chain plates, why not have new ones made enough longer so you could raise the cover enough to check and in the future, reapply sealant around them? On our boat, the covers can be raised about an inch, just enough to be able to check the sealant and reapply, but it is a real knuckle buster job.

 

[mitiempo]

Or if you are going to remove the chainplates have new ones made that are the same thickness top to bottom so they don't need the doublers where the toggle attaches. A bit of extra height would be a good idea as well.

 

[Ross]

Do you even need the cover?

 

[Rich Stidger]

If you lengthen the chain plates, you may need to shorten your stays.

 

[DianaOfBurlington]

Why are you not using quality stainless U-bolts for this application? However that was designed originally, it sucks (pardon mon francaise). The application is a recipe for disaster.

Before you go filling it with more sealant (and I pray you are using 5200!) you ought to check the condition of the structure just below it. From what I can see of that photo you have been taking water into the deck for some time.

I have posted often about U-bolts, most recently yesterday or the day before. If you search the posts you'll get good suggestions.

 

[RON20406]

This photo is not the clearest, but it shows the problem. There is no way to lift the cover up high enough to ensure that the slots for the plates are properly filled with sealant. When the chain plates are completely removed there is good access to the slots, but when pushing the plates back into place, the sealant is disturbed and, because the cover has to be installed at the same time, there is no way to be sure the slots are properly filled.

I only see two options. Either cut the cover so it can be put on in pieces or cut off the spacers that are welded to the chain plate.

Higgs, have you tried to inject the sealant under the cover plate with a West Systems syringe? This should give you the extra you're looking for without having to raise the plate or cut it. Unless you're dealing with an inferior engineering concept (which is doesn't seem to be) or a part in need of replacement, it is always better to use what you have and solve the problem accordingly. Good luck on your project, Ron

 

[mitiempo]

4200 or Sika Flex are much better choices. 5200's adhesive strength is not required and if you ever remove them it can pull gelcoat off the deck.

 

[Merlin Clark]

U bolts will place all the load to the underside of the deck, even with backing plates, where chainplates transfer the load to either the hull or a strong interior bulkhead that will be attached to the underside of the deck too but also glassed to the hull which spreads the load out over a greater area.

 

[Mitch Witt]

Unfortunately many things are not designed to be maintained. The other posts I see have some good simple suggestions. As you contemplate modifications check and be sure that none of the surrounding deck has water damage. Also, examine all SS parts that penetrate the deck for pitting, cracks & corrision. If old parts are determined viable have them cleaned and either electropolished or acid passivated before reassembly. If new parts are ordered make sure they have the same treatment (after any welded) - to forestall corrosion. Best of Luck, M Witt, SAMS ams

 

[sailaway78]

I wouldn't

I would not continue to try to force, or apply any epoxy or sealant under there without knowing whats there. That just adds more gunk, which almost never works. I like a couple other posters, would be very suspect of whats under there now. Whatever you decide to do, I would start with removal and inspection.

 

[kloudie1]

I agree with Nice&Easy on this one.. Can ya unbolt the plates from the hull and slide both the chainplates up along with the cover to inspect/clean/rebed the entire shooting match ??

 

[zeehag]

5200 is NOT a bedding compound. it is a GLUE ...not to be used for bedding chainplates or filling gaps nor caulking boats. it is a glue. where did i learn this????? I READ THE PACKAGING!!!!!!!!
silkaflex, boat life, 4200, polysulfide--are among bedding compounds. butyl tape is a good one also--see maine sail....
if the chainplates are older than 20 yrs, is a good idea to consider replacement. is not as costly as that sounds-- go to metal place to get metal, then have a fab artist make em--mine were specially made for under 100 dollars each. also change out the fasteners.

 

[mitiempo]

Agree 100%.

You should need a license to use 5200 on a boat.

 

[higgs]

Thanks for the comments. I am removing all chain plates. Decking area around chain plates has been inspected and is solid. The plates themselves attach to solid glass pads built into the hull, which is already very thick fiberglass.

I will not use 5200 or 4200. My problem remains as to how to be sure the deck openings are properly sealed since the covers cannot be lifted more than a quarter inch off the deck.

I think the real issue is what the cover plates actually do. It seems to me they help bed the sealant, protect the joint from damage, and act as a UV cover. What am I missing?

 

[mitiempo]

Mine were like that but for my new chainplates there is a separate cover plate. A chainplate will move against the deck a bit and the leaks I had I believe were caused by the cover plate moving with the chainplate. A separate cover plate allows some movement without breaking the seal.