Moving chainplates outboard (from "through deck" configuration), I have a question..

chrisncate · #1 (**permalink**) 02-21-2011

Moving chainplates outboard (from a "through deck" configuration), I have a question..

Alberg 30 btw..

Ideally, I'd like to go with a shape similar to this (this is a rough mock up, and the tang part would be further in of course), but I am wondering about the bends as roughly indicated in the cardboard mock up in the pic below. I have a metalworker who has my silicon bronze flat bar stock in hand, and he is waiting for my templates so he can get to work.

My question is whether or not I should make bends like that, strength wise, or if I should go with a more conservative approach and connect it to a built out toe rail like the second pic below (pic taken from some other boat, obviously).

The reason I do not want to connect the chainplates to the toe rail is due to the possibility of "flex" and leaks, and having my chainplates become part of my toe rail (thus combining two things I don't want to combine, really).

Thoughts on this? Would the chainplate design I did below hold ok structurally with those bends? The stock is 2"x 24"x 1/4" silicon bronze, and will be hand forged...

sailingdog · #2 (**permalink**) 02-21-2011

Chris—

Without the support of the toerail, the chainplates are far more likely to flex and if they do, it will cause the chainplates to fatigue. I think you do need to incorporate the chainplates into or with the toerail.

Don't forget, the angle of the mast tangs needs to be modified to match the angle from the new chainplates, which are now further outboard.

SlowButSteady · #3 (**permalink**) 02-21-2011

I've seen some older boats with outboard chainplates that have a sort of "rub-rail" (for lack of a better term) below the toe-rail, with the chainplate bolted below that. The chainplates bend over the top of this rub-rail, and are thus held just outboard of the toe-rail.

mitiempo · #4 (**permalink**) 02-21-2011

Like this:

gtod25 · #5 (**permalink**) 02-21-2011

but eventually compromised on this;

Full saga here

Boat is a Whitby 42, big daddy to your Alberg 30.

chrisncate · #6 (**permalink**) 02-21-2011

Quote:

Originally Posted by gtod25

but eventually compromised on this;

Full saga here

Boat is a Whitby 42, big daddy to your Alberg 30.

Wow, scary pics from your blog!

The stuff of nightmares..

I think you guys have confirmed the obvious for me, I will need to "build out" the toe rail in some manner in order to support them properly. Btw, I have never seen chainplates as long as the ones posted in the pic by SBS, do they go all the way around the boat? I like!

I want to not only replace the C/P's, I want to get rid of the tabbed gussets the old ones secured to inside to free up the room (always an issue on an A 30).

I am wondering about the best way/shape to go about these for my boat. I really want to experience the joy of a leak free toe rail for the very first time in my life, and I am thinking about how to achieve this with CP's attached in some manner to the toe rail.. again, thoughts?

mitiempo · #7 (**permalink**) 02-21-2011

You will sacrifice a few degrees of pointing ability with the chainplates mounted outboard. Not a disaster but something to be aware of.

I think chainplates can be seaaled properly through the deck. gtod's link is one example. The other issue is that most leaky chainplates have been ignored for 20 to 30 years. Properly done, which requires the most work, will take the longest time. Pulling them for inspection in 10 years and rebedding them won't take as long.