Why in the world---

[Windtherapy]

....didn't O'day weld the slotted deck piece to the chain plates? Why would you have chain plates run through a slotted metal piece on deck where water can penetrate instead of a welding that and making a tight seal! I bought new chain plates from Rudy and plan on replacing them and butyl the hell out of the cover and screws but now I am thinking about welding the slotted cover to the chain plates.

Is this a no no due to the chain plates possible moving even a 1/16'th of an inch and doing deck damage? Is that why they aren't welded--only reason I can think of. If that's the case, how can one keep water from rolling down onto the bulkheads ever? Are all chain plate designs equal on sailboats?

If I do not finish my overhaul of my new to me 26' this summer, I will replace the bulkheads this fall and beef up the chain plate anchoring area on the bulk heads like so many others have done. I think I will use 1/8'th inch thick aluminum sheets on the forward side of each chain plate area.

 

[CloudDiver]

If you use aluminum anywhere near your chain plates I will fly to Michigan and beat you about the neck and shoulders with a rubber hose...

 

[Jackdaw]

Are all chain plate designs equal on sailboats?

No. And IMHO O'day frankly has the worst. Due to both questionable design and construction techniques, I've seem more chain plates pulled straight out of the deck on O'days than on all other brands combined. One of the weak spots of otherwise OK boats.

 

[Stu Jackson]

Notwithstanding Jack's comments, if they look anything like mine, this is how to bed them with butyl

http://c34.org/bbs/index.php/topic,7265.msg49430.html#msg49430

Not so hard to do right.

 

[Maine Sail]

....didn't O'day weld the slotted deck piece to the chain plates? Why would you have chain plates run through a slotted metal piece on deck where water can penetrate instead of a welding that and making a tight seal!

Because these boats move.... The chain plates on most are supported by bulkheads that are usually screwed into place or in-other words "free floating". The deck and bulkhead may not be moving in unison thus the "floating" cover plate... This movement is why this type of design leaks so often.

 

[Windtherapy]

If you use aluminum anywhere near your chain plates I will fly to Michigan and beat you about the neck and shoulders with a rubber hose...

WHY?

 

[Windtherapy]

OK so I won't weld the slotted cover to the chain plate and just butyl the living hell out of it. It just doesn't make any sense to have a moving part that goes through the deck and therefore has the opportunity for water infiltration (but what do I know, I'm new to sailing). .

 

[CloudDiver]

WHY?

I'm just bustin your chops a little... You shouldn't use aluminum against stainless steel because of bi-metal corrosion. Now that's only a problem when exposed to water, and that re-enforcement is on the inside, but as you mentioned there are potential leaks with chain-plates. Hopefully a good application of butyl tape solves your issue and should not leak since it remains flexible. Post some pics of your chain plates, inside and outside, and maybe we can give you some better ideas on how to re-enforce them without using aluminum.

 

[Windtherapy]

You know after I sent the WHY I thought immediately that it would be because of two dissimilar metals.

 

[Indysailor]

OK so I won't weld the slotted cover to the chain plate and just butyl the living hell out of it. It just doesn't make any sense to have a moving part that goes through the deck and therefore has the opportunity for water infiltration (but what do I know, I'm new to sailing). .

I don't know that you have to "butyl the hell out of it". Just get good butyl tape and follow the instructions Mainesail has made available in a variety of places. I followed his examples and have had great results.

 

[Benny17441]

That is the answer, it is a floating plate necessary to allow movement. Understand that production boats are all about offering the best product possible at an affordable cost. The slotted plate is a simple proven design that allows a part to be fabricated with existing tooling at a low cost. The problem is that timely maintenance is usually overlooked well past the point that the original weather proofing was good for. Boats designed with components that will figuratively perform forever are usually in a price class out of reach for most.

 

[Ward H]

Yep, that trim piece is just that, a trim piece covering the slot for the chain plate. I replaced mine.
I taped the inside, brushed the slot with epoxy and filled the trim plates screw holes with epoxy. I then wrapped butyl tape around the chain plate low enough that the when I installed the chain plate butyl tape was pulled down into the slot nice and tight. Then I put another rolled piece of butyl tape on top of that so when I pushed the trim plate down some butyl squeezed up between the chain plate and trip plate. Screwed down the trim plate and was done.
I saw someone once on here who did weld the trim plates to the chain plates but you still need to seal the water out well.
Consider this. If you weld the plates, then bolt them on the bulkhead they will not adjust position so you cannot screw them down tight to tightly seal under the trim plates.

 

[Jackdaw]

That is the answer, it is a floating plate necessary to allow movement. Understand that production boats are all about offering the best product possible at an affordable cost. The slotted plate is a simple proven design that allows a part to be fabricated with existing tooling at a low cost. The problem is that timely maintenance is usually overlooked well past the point that the original weather proofing was good for. Boats designed with components that will figuratively perform forever are usually in a price class out of reach for most.

I see the point you're trying to make but it's not totally correct.

Though better design it it is very possible for even production builders to make much better, much more secure chainplates.

1) Don't put deck penetrations through core. This includes chainplates. Smart builders incorporate their deck hardware layout when designing the deck, and make those area solid glass. Even it it ends up leaking, it's super solid. On boats that do this, normally areas on the deck that are solid don't have antiskid.

2) Don't use structural wood. Tie the chainplates to the hull with a stainless steel rod. Or tie it directly to the hull. Skipping the wooden bulkhead again allows leaks to not compromise the boat.

3) Design it stiff. That flexing is a function of design. Stiffer boats flex less and don't work the chainplate sealant away at nearly the same rate.

 

[CloudDiver]

At the risk of getting my head chopped off... because we all know silicone has no place on sailboat (except the proper products for window use only), why not try Dow Corning 795 in this application (chain-plates)? I only say this because of 795's expansion/contraction (joint movement capability) of +/- 50%? I know butyl tape remains flexible indefinitely as well, but at least 795 cures and I think its flexibility/elongation/compression is actually better than butyl rubber. BTW, keep in mind 795 is actually defined as a structural sealant or building sealant, not a window adhesive. Also, there is a 'correct' product that actually dissolves and removes cured silicone products, DS-2025 Silicone Cleaning Solvent (Dow Corning).

 

[25yearslater]

At the risk of getting my head chopped off... because we all know silicone has no place on sailboat (except the proper products for window use only), why not try Dow Corning 795 in this application (chain-plates)? I only say this because of 795's expansion/contraction (joint movement capability) of +/- 50%? I know butyl tape remains flexible indefinitely as well, but at least 795 cures and I think its flexibility/elongation/compression is actually better than butyl rubber. BTW, keep in mind 795 is calling a structural sealant or building sealant, not just a window adhesive. Also, there is a 'correct' product that actually dissolves and removes cured silicone products, DS-2025 Silicone Cleaning Solvent (Dow Corning).

Into fourth year with the same chainplate/decorative cover setup common to Oday. I also used 795 and have yet to see a drip inside. I know it can't penetrate the core since I put a thickened epoxy window around the area during the restoration. I also coated the holes in the plywood bulkheads with epoxy before securing the chainplates. No problems thus far.

 

[Davidasailor26]

MHO O'day frankly has the worst. Due to both questionable design and construction techniques, I've seem more chain plates pulled straight out of the deck on O'days than on all other brands combined. One of the weak spots of otherwise OK boats.

Jackdaw, I'm curious if you've seen these types of problems on larger odays or just the smaller ones. Our 28 had the chainplates go to stainless rods and down to the pan as you reference in your later post, which I always thought was pretty robust.

 

[Stu Jackson]

because we all know silicone has no place on sailboat (except the proper products for window use only)

Yes, but I'd modify that a tad: only for Beckson ports.

 

[Jackdaw]

Jackdaw, I'm curious if you've seen these types of problems on larger odays or just the smaller ones. Our 28 had the chainplates go to stainless rods and down to the pan as you reference in your later post, which I always thought was pretty robust.

The oday 28 (which I've always liked) is a rare o'day where the mast is not set over the bulkhead. So they have to use rods which is good. When the mast is at the bulkhead like on the 25, 26, 34 etc the boat uses chainplates set into the wood bulkhead, like this 34. The 34 does use rod for the aft lower.

 

[Davidasailor26]

The oday 28 (which I've always liked) is a rare o'day where the mast is not set over the bulkhead. So they have to use rods which is good. When the mast is at the bulkhead like on the 25, 26, 34 etc the boat uses chainplates set into the wood bulkhead, like this 34. The 34 does use rod for the aft lower.

Thanks for the clarification. I didn't know that the 34 or any of the 28+ models had the bulkhead set arrangement.

 

[Pat]

The O'day 302 and 322 both had the chainplates/rod rigging tied to the pan/structure of the boat...as noted above the O'Day 28 also had rod rigging tying the chainplate
system to the structure of the boat.....