Busted!

Nov 22, 2008
3,562
Endeavour 32 Portland, Maine
I put this picture of one of Strider's chainplates in a Facebook album so I could link to it for my previous post. It wasn't supposed to show up on Facebook but, due to some FB weirdness, went out to several friends newsfeeds.



One of the friends is a retired Transport Canada inspector, now a boat surveyor and consultant so I have to take seriously the comments he posted about the photo.

Dissimilar metals, poor quality stainless steel, to short cotter pin and wrong screws attaching the chainplate cover.... Bet the deck core is pretty rotten underneath..

On scores of boats I've surveyed I've found water ingress into the core through the cover screws. Agreed on the dissimilar metals, I'd want to look closer.... But then as a surveyor I'd want this whole lot taken apart for closer inspection because I suspect there is insipit corrosion cracking lurking.....
Maybe Ken will join us here for further discussion but here is my response:

No dissimilar metals. Everything in the picture is stainless but all the stainless on Strider is stained after after 3500 nm of sailing last year. The turnbuckles are Sta Lok which is a pretty good brand, but even their upper ends are stained. Something about the lighting makes the staining look worse than it is but I've got to clean the stainless soon.

The clevis pin is not the one that came with the turnbuckles. The yard that replaced my standing rigging lost the original pin and replaced it with one on hand. It's an experienced yard so, other than the lack of as nice a champher on the end of the pin, I wasn't too concerned. Looking at the difference in the amount of staining between the two sides now however, I think I'll swap that pin out when I can.

As for the cotter, that's the way the great rigger Rod Stephens told me it should be done back when both Ken and I were working with him on the design of the Corwith Cramer (seen in the animated GIF in the previous post). The short legs are sufficient to keep the pin in place. Minimum bending avoids changes to the metal. If something does snag, the shorter the legs, the less leverage there is to bend them further. Here is a picture of Ken, Rod, myself, and the other committee members taken aboard the Westward.



Ken is fourth from right looking sideways at Irving Johnson. Rod Stephens is second from right and I'm third from left.

Cover plate screws into core are a major source of deck problems. However, the deck on the boat is solid glass and quite thick in way of the chainplates so no concern there. The chainplates are not dependent on the cover plates to stay watertight. When re-installing them, I cut out a wedge shaped area which is filled with butyl tape caulk. That was left proud and the cover plates put down over 4200 bedding compound which compressed the butyl and then squirted up through the cover plate slot when the screws were tightened. There has not been a hint of leakage around the chainplates since. Since these screws dead end in solid glass and there is no load on them, there didn't seem to be any point in changing from what was already on the boat. The screws were each removed individually after all the bedding had set up and reinserted coated in more bedding compound.

The chainplate installation on these boats is a bit unusual but very robust. I corrected the angles when re-installing them as you can see in this drawing which also shows the butyl tape caulking.



More details of the chainplate beefing up and re-installation, along with new lower shroud mast tangs, can be found here:

http://www.cruisingonstrider.us/2011WinterProjects.htm

I am keeping my eye on those vertical stain lines which can be starting points for crevice corrosion. I spent hours polishing the fittings before reinstalling them trying to work down below the surface metal changes. Evidently, I didn't go far enough. However, as described in the link, the upper shroud chainplates were doubled in thickness as part of the project with new 316 s.s. so I'm not concerned about their integrity.
 
Feb 20, 2011
7,990
Island Packet 35 Tucson, AZ/San Carlos, MX
I wasn't going to say anything about that, figuring you were looking for a new boat to sail to Cuba upon.

Caveat emptor, and all that. ;)
 
Feb 26, 2004
22,759
Catalina 34 224 Maple Bay, BC, Canada
Our chainplate detail thru and above the deck is identical to yours. I also use butyl tape, although no 4200, I used butyl tape where you used the 4200. Works just great on the three or four of my six I've done in the past year.
 
Mar 26, 2011
3,399
Corsair F-24 MK I Deale, MD
I'd also watch that bent toggle; I've had 2 of those crack across the tops. Stress from manufacture, I'm sure. Keep them visible.
 
Oct 3, 2007
2
- - Orange Park
Great old photo of the group on Westward. I realized in a second glance that Parker was there too, and Wallace Stark of course. Thanks for sharing.
 
Apr 13, 2009
53
Irwin 33 St Pete, FL
Good answer to fair comments. He made his judgement based only on a photograph, which is not quite the same as eyes on deck, so to speak.
Nice to see a few people in the photo I have never met in person but respect deeply for their impact on sailing and sail training. Sadly I will never meet the ones you mention.