Rust or degalvanized issue with anchor shackle

[Zoid]

Take a look at the attached picture. At the end of my first year cruising the anchor shackle had considerable rust build up (it was brand new at the start of the season). I soaked it in some water and vinegar and the rust came right off. Problem solved, or so I thought. I put it back on and after a week or so just in the air (not in the water) it started to look like the picture. Has it lost its galvanization? Any thoughts on suggestions on what to do?

[rdempsey]

If it looks like that after 1 year I would buy a new one.
Or you can use cold galvanizing spray to extend its life.

[Cheechako]

Buy a new one. many of the ones sold today in "marine stores" are from asia and the galvanizing is just no good. Not sure why.... other than those places don't specify exactly what they want, because they just want to make a fast profit sale.
Consider something from McMaster-Carr or the like. I often used forged stainless without issues, but lets not open that can of worms!

[rwidman]

For the $5 that piece that costs, I would just replace it and not worry about trying to repair it. You should probably go to the marine store, not the home center.

[Zoid]

This is the one that came with the boat that was purchased new from Lagoon. Everything else has been good to great quality, just not sure why this one deteriorated quickly. I'm Sicily right now and the selection generally is of the cheaper Chinese options and for an anchor shackle I don't want to risk it. Looking for a replacement but just wanted to see if others had seen this or if my vinegar and water bath had done more damage than good.

[monte]

Ours always looks like that Kenny. Funnily I noticed last week our year old Lagoon shackle pin has snapped inside the thread of the shackle and appears to be holding on by a thread, literally. I have a stainless one as backup with the original for now till the next chandlery.


"I think multihulls require less IQ to sail than a monohull" - Duckwheat

[onestepcsy37]

Looking at your photo it appears that you may be able to use a shackle one size larger, always a good thing. I'm not certain, but it also appears your shackle is not wired shut, a giant nono.

And like everyone else says buy a new one. Buy two and have a spare.

[barnakiel]

Yep. Cheap shackle. Upgrade.

I too think it looks maybe one since up will fit.

Mice yours unless you have a good reason not to.

b.

[monte]

Those shackles have a recessed head that takes an Allen key. No way to seize it I guess. Would be unlucky to have an anchor shackle loosen itself once it gets a bit crusty. We just inspect ours occasionally (luckily as it's about to carc it) will likely be a hacksaw job...


"I think multihulls require less IQ to sail than a monohull" - Duckwheat

[Seymore]

Replace the shackle, specifying firmly that the new shackle be "hot dipped galvanized". Ensure that both the shackle and its pin are "hot dipped galvanized", and that neither is painted.

In the picture, it looks like the chain and anchor are hot dipped galvanized. The shackle was merely electrogalvanized or painted or varnished. You can see the difference in the store, looking at the shackle, it's obvious.

In "hot dip galvanizing" the part is dipped into molten zinc, which puts a relatively thick rough nonporous coating on it.

In "electrogalvanizing" the part is electroplated with zinc in an electroplating bath. The coating looks OK in the store, but it's thin and porous, worthless in a seagoing environment, as you've seen.

I've found zinc rich paint to be one step down from electrogalvanizing. There can be a good zinc buildup, but it's too porous to be of any value.

Edit: Vinegar is a weak acid. It ate the light rust off, leaving bare steel which then rusted again real fast.

[Zoid]

Thanks everyone for your responses, this helps a lot. Now if I could only find a decent chandlery in southern Italy. A trip to Malta might be the answer.

[rwidman]

Originally Posted by monte

Those shackles have a recessed head that takes an Allen key. No way to seize it I guess. ..........

That's when you use thread locking compound.

Yea, the kind you can lock down with wire are a better choice unless the shackle has to pass through a hole or bracket and gets hung up on it.

[monte]

Kenny svb do cheap fast deliveries all over Europe. Have a browse of the site and it won't take long to fill up a little box of stuff you 'need'
http://www.svb24.com/en/galvanised-s...-shackles.html

[Zoid]

Seymore, I think you are right about the galvanizing method of the shackle. Monte, thanks as always for your input, always great to hear from you. SVB it is going to be, now I just need to stay still long enough to receive delivery. Thanks again.

[monte]

No worries Kenny, cheers. Also if it's just the shackle you need, a lot of fishing harbours have a small chandlery for the fishing fleet that usually stocks decent hardware, just not so much yachty stuff, a local professional rigger will likely sell you one out of stock. Where are you off to this year?