Anchors, One to watch

Does seem highly unlikely that the shank fractured. The one I tested was HSLA, a strong steel widely used in modern engineering. It is tough, strong and unaffected by heat treatment.

The man who suggested two shackles is probably close to the truth.
 
When we're underway (or should it be underweigh?), our (non) Rocna anchor is restrained by more than just the anchor chain. :rolleyes:
 
Thank you for the link-I always find your anchoring thoughts interesting and enlightening.
 
Poor fabrication?. Brittle fracture?, (although not very cold to produce brittle fracture where they located). It would have been good to get more background information to help to understand the cause.
 
CAPTAIN FANTASTIC said:
Poor fabrication?. Brittle fracture?, (although not very cold to produce brittle fracture where they located). It would have been good to get more background information to help to understand the cause.
Click to expand...

See post #3. HSLA steels are not susceptible to brittle fracture down to at least -40C. Ductile/brittle transition temp of HSLA 100, a widely used grade, is -80C
 
I have a 20 Kg Rocna that is now my backup anchor (primary is a Mantus 65 lb) and I find it extremely unlikely that the shank could have broken at the eye. Of course anything is possible but I'm inclined to think that there was second shackle or swivel that parted ways.
 
If the anchor had fractured and fallen into the depths as claimed, there would still be the broken part of the anchor from the eye upwards, remaining in the deck recess pictured.
 
I'm equally questioning but I'm not prepared to say the OP is trolling or offers a fictional account. There is a distinct absence of information - we rely on the integrity of the OP.

Its a yacht - anything can happen.

I note Vyv's comments on the steel - that is not to say its the steel used now.

If there were an issue with the steel then CMP do not make 'single' anchors they make lots from the same raw materials - and I would thus expect more failures - not one isolated case (by a user who admits to being something of a neophyte - so hardly likely to stress any of his kit)


I tested an anchor recently and bent the shank - it was obvious - but then I look for these things. I commented to the manufacturer - they admitted it was mild steel - but did not say why it was not more robust.


A point I would make, and my post was not to troll:

It is easy every time you are on the bow - look at your anchor, a quick glance. Is the shank true, is the toe bent (more than designed) does the mousing look tired, has the Loctite failed? You should be doing the same quick check with all of your shackles etc etc - just add your anchor to the list. If you have bought shackles from a reputable supplier - they will not fail - except through operator error.

Like Norman - when at sea our anchor is tied down (stops it wobbling), the chain is slack (so as not to keep the windlass underload). Our chain is also restrained with a chain hook secured independent of the windlass - real belt and braces. Our shackles are all gal alloy steel (Crosby, G209a), bow shackles with the pin through the chain. We only use one shackle, no swivel. On most of our anchors we use 3/8th" shackles (UTS 10t) but on one anchor the shank is a bit beefy and to stop the shackle 'locking up' we use a 1/2" shackle (that looks enormous compared to the 3/8th") and use a CMP Titan Black Pin shackle (though would not use the 3/8th" version - Crosby are, much, better).

As an aside - I am trialling use of gal hammerlocks - instead of shackles.

Note some anchors have enjoyed no independent tests, Vulcan, Lewmar's fortress clones (the LFX), Mantus and in the wings Lewmar's new steel anchor and Viking - both yet to be released. People are buying them - but there are enough 'tested' anchors out there, Rocna, Supreme, Spade, Ultra, Excel, Fortress and all of these have been Proof Tested and holding capacity defined - such that no-one need be the 'white rat'. Excepting the fact we have no idea if the 'tested' anchors use the same raw materials as the one bought - we rely on the integrity of the manufacturer - make you own judgements.

Jonathan
 
I do find the idea that the shackle eye on the shank suddenly and catastrophically failed and there were no previous signs of stress on the shank (or shackle) - unusual and unlikely. But anything is possible, however unlikely

However I would not be surprised that the shackle pin, on many anchors I see, becomes loose and the anchor fall off. Thinking back many shackles are not moused and many are moused using cable ties (that deteriorate in the sun) or using a rusting wire. Most anchors I see are simply held tight against the bow roller with the tension on the chain and windlass and no sign of a chain lock (which would not secure the anchor independently anyway) not the anchor lashed (there are usually 2 holes in the shank conveniently located for just this task).

And do not drill a hole in the shank so as to allow a locking pin to secure the anchor to adjacent holes in your bow roller.(I've seen it). If the shank was meant to be perforated - it would be! and the hole you drill will rust.

Obviously many people might be using Loctite to secure their shackles - but I doubt it.

I am sure the OP lost his anchor. Just make sure your mechanisms and techniques to secure your anchor are adequate (and better - belt and braces). And check the trueness of your anchor - they do bend.

Do check the bitter end of your chain - make sure it is lashed securely (such that you can cut it free in an emergency) - if your anchor is not lashed AND you do not use a chain lock - AND your clutch slips (it has happened) - you might deploy your anchor and chain over the seabed in 1,000m!

Now that would be embarrassing - and expensive.


Jonathan
 
Next XXXwhatever anchor will have disappeared because it was cleverly discovered it was made of cheap effervescent metal, just adding salt water and away it slowly disappeared into a bubbling cloud of gas :rolleyes:
 
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