Chainplates - Redesign?

[Wotname]

Originally Posted by RaymondR

I would not do that with SS chain plates. SS is very prone to failure when welded and even 316L is not immune from the process which causes the cracking problem.
........

So how about silver solder - would that be a safer option?

[TeddyDiver]

Composite chain plates! No holes when it's done.

[Wotname]

Originally Posted by RaymondR

I would not do that with SS chain plates. SS is very prone to failure when welded and even 316L is not immune from the process which causes the cracking problem......

And yet I see steel boats with welded on SS tangs for all sorts of things including standing rigging - are they bad too?

[RaymondR]

Originally Posted by Wotname

So how about silver solder - would that be a safer option?

Silver solder would be better, not as much heat and more evenly applied. No heat at all avoids the problem though.

[Cheechako]

Originally Posted by Jim Cate

would not those welds create stress risers and potential weak points in the chain plate itself?

We've had similarly shaped collars that were simply screwed to the deck, but not welded to the plate... dunno if they really help, though!

Jim

Assuming the plate size is substantial in the first place, I don't think they will, but any welding could create an area more prone to corrosion if not done properly for sure. The TIG welding could just be done with minimum penetration to hold the plate on. It's not a structural weld and if properly dressed, passivated or etc after should be fine.
The advantage is at the chainplate vertical surfaces you are not relying on sealant alone to block water intrusion. A slip on chainplate cover does allow that. Sealant gets old, hard and shrinks to some extent. But any new chainplates, properly done will last 20-40 years anyway. So....
SS is not prone to failure when welded if done properly.
(ex Aircraft welding engineer)

[Wotname]

Originally Posted by Cheechako

Assuming the plate size is substantial in the first place, I don't think they will, but any welding could create an area more prone to corrosion if not done properly for sure. The TIG welding could just be done with minimum penetration to hold the plate on. It's not a structural weld and if properly dressed, passivated or etc after should be fine.
The advantage is at the chainplate vertical surfaces you are not relying on sealant alone to block water intrusion. A slip on chainplate cover does allow that. Sealant gets old, hard and shrinks to some extent. But any new chainplates, properly done will last 20-40 years anyway. So....
SS is not prone to failure when welded if done properly.
(ex Aircraft welding engineer)

Emphasised section - that's it in a nutshell!

Thanks for posting an alternative view re SS welding.

[RaymondR]

Originally Posted by Wotname

And yet I see steel boats with welded on SS tangs for all sorts of things including standing rigging - are they bad too?

In comparison with carbon steel SS is a very poor performer from both ease of making reliable welds and fatigue failures viewpoints. This is the reason that your insurance company will insist that you replace your SS rigging every ten years.

There is a grade of 316 SS called 316L which is more suited to welding.