Anchor maintenance

[Alan Wheeler]

Surely if SS shackles were in fact The Grim Reapers playthings they wouldn't be a very very common item to see in use.

Yeah but what else do you use that doesn't corrode. A shackle anywhere else is in a less "mission critical" situation. If it breaks, you know and can replace it. If it is mission critical like Americas cup, then you use Titanimum. It is only under water that SST becomes a big issue due to electrical action working on the metal, especially around welds and forging work. This changes the crystiline state just enough to create and un-equal metal type and create a crevice corrosion. The SST item looks fine, free of rust but fails seemingly for no reason.

[skipperaris]

Originally Posted by Alan Wheeler

Yeah but what else do you use that doesn't corrode.

Rope. It doesn't corrode. And it is used at the other end of the chain anyway.

[Alan Wheeler]

Well yes, but no. If I understand Gmac correctly, he was talking SST shackels in general use above water. Like rigging etc. My reply to that was also in regards to SST shackels in general use above waterline such as Rigging use etc.
For Chain to Anchor connection, simple! A Tested Galve shackle. The chains Galv, the Anchor is most usually Galv so the Shackle should be Galve.

Here is a thought.
Back to anchoring, A SST shackle should ONLY be used if the Chain and the Anchor is SST as well. Think about a Calv/steel anchor buried in Ground, the boat above which has all sorts of electrical currents created in it and a chain connecting the two. Surely an dissimilar metal like a SST shackle is going to have a small electrical current produced across it. If the chain is SST, then the same goes for each and every link. Galv items are also subject to this, but the zinc on the items will be "sacrificing" to protect it all.
thoughts???

[GMac]

I was talking for anchoring and upwards but definatly not permenant immersion. Personally I'd use a SS before most 'tested' shackles, them little bu**ers being very high tensile.

Did you note how many 'mission critical' fittings, fixtures and keel supporting gear made of titanium let go during the last few Round the World races? So many they swapped most out for SS while in Aussie. Calculated to have stupid amounts of safety margin and still went snap. 3" rams going pop. That is spooky.

There is masses of SS connections on galv gear and we've yet to see anything spooky happening between the differing metals. Not saying this isn't any but I suspect not enough to be an issue.

Only realy seen one very spooky bit of SS anchor gear but when we sussed further (it was our gear supplied) we found it lived on bare carbon fibre in the anchor locker. 10mm to 3-4mm in 6 months. Chain replaced and locker lined. Last I spoke to them it was 4 years later and all was fine.

We make the floaty ring things found in marinas out of 316. Many have been living for many many years now without many worries. The only real worry is when you have a leaking boat, volts that is. The current will travel down the mooring lines and out through the legs of the floater. This has cause a small amout of wastage on some but still not that much considering the years taken.

Idealy you want to keep anchor metals the same but a smidgen of SS in a galv one does not seem to cause any problems. We have done a pile of all SS rodes and apart from the above one, without any problems. Actually the amount of SS being requested for anchoring gear is sky rocketing. People just love the bling on the pointy end.

I think when it comes down to it most people either swap out for new or do a Maui by hooking land and losing their gear long before the SS gets to be a if any issue.

[seafox]

Those shinney stainless anchors sure look pretty.

[cat man do]

Originally Posted by seafox

Those shinney stainless anchors sure look pretty.

These ones are real purdy,

And built in NZ by Manson,

Manson Anchors. Stainless Steel Ray Anchor

Dave

[seafox]

I wonder how they get the shackle off when it seizes?

[GMac]

I've fondled those very anchors. 2 x 650kg (if I remember right) of hand polished A1 grade Bling.

They did get me a tad excited, so much so I nearly had to have a cold shower. Anyone see mental heath issues just there

A pair of those hanging of your cat would look flash Cat Man. Hold you pretty well I would think

[Alan Wheeler]

Yeah at 650Kg a piece, it would be pointy end facing directly down.
Hmmmm, 1300KG! so the utes overloaded huh?!?

[cat man do]

Yep, definetly be aglub with those big puppy's on the front.

I know what you mean about getting exited fondling the shiny stuff GMac, did the same with my Andersen winches. oooohh baby

Scary

Dave

[skipperaris]

Originally Posted by seafox

I wonder how they get the shackle off when it seizes?

~ a shackle may have been riveted on its threaded part against the u-bolt for safety
~ a shackle may have been deformed -bent in a variety of ways - usually by too much load making it difficult to unscrew
~ a shackle pin head may shear off while attempting to undo the pin
~ a shackle may be suffering of some other disease that I cannot think of just now

BUT otherwise a shackle never seizes.
Means at your disposal to undo a shackle are:
- the wife
- WD40 for easy cases of mild steel shackles
- heating with a blow torch for harder cases (severe rusting) of mild steel shackles. (never heat stainless steel above 400 C - it changes the crystalline structure of the material and leads to brittle fracture)
- a vice to hold the head and a long lever to go through the U

If none of this works try black magic or send it to me.

[craigsmith]

Originally Posted by GMac

I've fondled those very anchors. 2 x 650kg (if I remember right) of hand polished A1 grade Bling.

They did get me a tad excited, so much so I nearly had to have a cold shower.

So how does this do it for you?

[GMac]

I'm off to have a cold shower right now

[craigsmith]

:kissy:

[GMac]

Now your just teasing