Playing with Fire - Anchor Question

To return to original questions.....

Size of anchor. We have a Bavaria 38 and a 20kg Rocna (shaft still straight). It holds fine in high winds (60+ knots on occasion) on 8mm chain. The OPs Bavaria 36 will be fine with the 16kg Mason. No harm in going up a size but if Manson recommend 16, go with it.

Swivel. We have used Knog swivels for years. That’s because we were forever getting the anchor up to the roller inverted and it was a pain to sort out without the swivel. Fitted originally straight to the anchor shank, we gave that up in favour of chain, swivel, chain, shackle anchor because we bent the jaws on the first swivel we fitted. Read up on various threads on here about the bit of chain and it works.
We anchor most days through the season in Greece, so the anchor gets a lot of use. We fitted the Rocna 7 years ago now and I sleep soundly most nights. Last couple have been exciting with the winds we’ve been getting but the hook hasn’t budged. Going to be fun getting it out though.
 
SiteSurfer said:
I spoke to the nice chaps at Force 4 and they will allow me to carry the anchor out the back door and try it on the boat (the Chandlery is next to the boat in a spookily convenient turn of events!) :)
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Final tip; attach borrowed anchor with some string when playing, else pch a Seasearcher magnet! You wouldn't be the first :)
 
While you are checking that the anchor fits the bow roller, also check that there is enough room for your swivel/chain/shackle between the anchor and the windlass gypsy for the anchor to self stow on the roller.
 
SiteSurfer said:
Just to clarify the offshore thing.
The Manson website asks whether you would be going 'offshore' and suggests a heavier anchor if that's the case (at least they did for my weight of boat).

I'm not certain that their definition of offshore is the same as yours, I took it to mean 'venturing away into unknown grounds in all manner of conditions' rather than 'dropping a hook in 50m of water'
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I take it to mean - do you pick your weather to anchor overninght or, are you living on anchor regardless. Strangely, Manson tables recommend 27 kg for my boat (12m 9,000kgs) whereas when I bought the Supreme a few years ago, 20 kg was recommended size and has proven quite adequate in some quite gusty blows. I use 10mm chain with Kong swivel and short length of chain to anchor + snubber of course.
 
SiteSurfer said:
Just to clarify the offshore thing.
The Manson website asks whether you would be going 'offshore' and suggests a heavier anchor if that's the case (at least they did for my weight of boat).

I'm not certain that their definition of offshore is the same as yours, I took it to mean 'venturing away into unknown grounds in all manner of conditions' rather than 'dropping a hook in 50m of water'
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Apparently offshore waters can be even deeper than 50m, but I did understand - :)

I'd not ignore Knox, they were spuiking some discounts at a Scots boat show - Kip? - I don't know when it was, is? but I"d contact them and ask - if you do not ask, you will not know. I know you might be a bit far from Scotland (but in Oz that distance is 'just up the road') but maybe the deal will be on for mail order - ask?

I find it refreshing the numbers who are questioning the mantra of 'oversizing anchors'.

If anchor makers recommended anchor that were undersized and did not perform - there would be a rash of threads and the insurance companies would hit the manufacturers - hard.
 
SiteSurfer said:
We (family) would normally anchor in 5m of water around the Solent in less then F6 conditions.
Its because we are thinking about venturing a bit further that I am checking in advance whilst i am in the process of buying it all.
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Thanks SiteSurfer.

Nothing the recommended size of anchor would not deal with in your normal day to day usage. If you are planning longer trips where the weather is a bit more lively, e.g. the north west coast of Scotland or western Ireland then going up a size is worth considering.

Personally, I like the Knox but I am not going down the "best anchor road" :)
 
For some reason the image did not materialise

But for some reason, because I'm psychic, I deduce it is a Titan Black pin shackle. The strength of 7t is the UTS (the min at which it will break). It is the Working Load Limit you need - it would be higher, or as close to, the WLL of the chain as possible. You also need to check that the shackle pin will fit the chain and the bow of the shackle fit the anchor.

There were a couple of threads recently on getting a shackle to fit the chain, metric chain is a bit parsimonious and the hole in the link is a bit small. NormanS suggests unit a drift and Vyv a vice to enlarge the hole, of G30 or G40 chain, as this will allow use of a slightly larger shackle but allowing the shackle to have a higher WLL than the chain.

But I'd also look at replacing the Titan Black pin with a Crosby G209a - which has the same dimensions - but is a better shackle. The Crosby might be a bit dearer a very few stg - but it is not significant. You can get Crosby shackles from Knox and Tecni - but get the G209a, Platinum Pin, not the, confusingly called, G209.

And the pins are not platinum :). they are just aluminium (silver coloured) painted.

Jonathan
 
If you can comfortably manage the larger anchor then that would be my pick. In the weather some forum members have been experiencing lately, I doubt you would be regretting the decision.

People sometimes become carried away with the drawback of what is only a small weight difference. 4 kg is only the same as a 3m length of your 8mm chain.

Swivels do have some useful purposes and are fine if they are a quality product installed correctly. A Kong swivel with few chain links between the anchor and swivel fits this description. I understand you already have the swivel, in which case I would use it, but for others I would suggest trying without the swivel at first. The cost savings help offset the cost of a better anchor.
 
The 7T WLL is for the 3/4" shackle shown in the picture on the 7/16" page. You might struggle to get this to fit the 8mm chain! Confusing or what? If you look on the Titan table the 5/16" shackle has a 3/8" (10mm) pin and should fit the chain and has a WLL of 750kg (BL 4500kg). Best check the shackle sizes at the same time you check the anchor fitment. As said above the whole system should have a similar WLL and break loads - including cleats on the deck.

sorry - crossed with above posts
 
If I interpret correctly 4kg difference in weight is a difference of 100stg - which to some will be peanuts, to many - not to be sniffed at and better in the OP's pocket than in that of the anchor maker - if there is no justification - other than gut feel.

In the grand scheme of things - anchor are cheap - except when you need to pay 100stg more.

Jonathan

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And don't buy the Yellow Pin shackles - they are not as good!
 
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Ok, so some great thoughts posted (thanks to all).

I don't have the swivel yet (my last one would have been too small), and understand about the shackle - the image clearly wasn't the right one for the job!
I'll look at the Crosby shackle - that's a name that crops up a lot (probably with reasons) and in saving the 89 pounds on the swivel I am almost at the 20kg anchor anyway.

My mantra is to buy once and crack on, it seems that whilst I don't absolutely categorically need the heavier anchor, it may prove useful in the (unknown) future and especially if I am saving the best part of the cost by not adding the swivel - then perhaps this is a reasonable approach.

I'll check the fitting, placements and storage before committing and act accordingly.

I may need to replace the chain as on inspection, whilst serviceable did appear to be a bit ropey in places where the galv had worn off.
 
If you have not lost 'steel' then you could re-galv the chain.

The 8mm is the nominal size of the wire from which the chain is made. It is then galvanised which will add around 100 micron of coating. If you 'lose' 10% of wire steel thickness the chain should be retired. The chain loses steel at the crowns, the curve of the link where 2 links rub and along the length of the link, where they abrade on the seabed. If the chain has not been 'end for ended' then unworn chain will be in the locker and worn chain near the anchor.

If you want to evaluate the issues of regal - and where to do it - I'd start a new thread - or use the search facility, it is a common issue here, on PBO (and common practice in the UK).

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The first few links, nearest the shackle (and anchor) preferentially corrode and would normally be chopped of, maybe 3 links. That would be normal and might be an annual procedure. So don't measure them, chop them off. Measure from a few metres back. But if you need to enlarge the link to get the shackle pin to fit - remember you will need to enlarge the new end link when you chop the corroded links off - or your new shackle will not fit!

Jonathan
 
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Neeves said:
But I'd also look at replacing the Titan Black pin with a Crosby G209a - which has the same dimensions - but is a better shackle.
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My vote would also be for the Crosby 209A, but there is only a small difference between this and the Titan black (or brown) so if you have the Titan I would not contemplate going to the expense and trouble for a swap.

Be aware they are not exactly the same size. The Titan has a slightly smaller pin diameter than the Crosby in some sizes. So the Titan will sometimes fit where the Crosby is too large. For example the Titan Black 3/8 pin is 11mm the Crosby 209A 3/8 is 11.2mm.

The actual dimensions of shackles often differ a little from the specifications so check on an actual shackle if it close. Usually the pin diameter is the limiting factor.

Don’t assume if Titan black fits that the same sized Crosby 209A will also fit.

It is also worth checking the chosen shackle does not have a tendency to bind or lock in place with oblique pull. This is something you have to try with the actual anchor, chain and shackle combination. If this does happen a different shackle will be a better choice.
 
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SiteSurfer said:
The chain is on the boat and is 8mm.
The anchor would be a Manson Supreme 16kg Galvanised - the boat is a Bavaria 36.
The swivel would be a Kong
The shackle would be a Titan from Force 4
The middle bit of chain (as I understand it) would be 3 or 4 links.

.
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The chain sounds good to me.
Anchor is on the light side - exactly the decision I made for my intended use.
I have used swivels but don't now - don't miss them either.
As already mentioned the Titans come in different grades, mine says 3/4 ton (I think) less than the chain but ok for me. I chose a shackle, from the bin, that had some thread protruding so I could peen it over. The galvanizing is holding up ok, I think they are hot dipped, much better than the usual offerings.

Going oversize is fine if you have a winch and stow the thing on the bow. For smaller boats it can raise(sic) problems. Bulky anchors are also a pain if you want to stow the anchor inboard and/or get it through the pulpit.
 
I'll find out tomorrow if the anchor fits and work backwards from there, the only question left for me then - is the one about the shackle.

I'm going to ask this because I need to be certain. Is the working load stamped on the shackle comprised of a calculation of the weight of the boat + a bit added on for luck or some other figure?

Just wanting to make sure I buy the right damn stuff.
 
A far a I can ascertain the Titan Brown Pin shackle is a Yellow Pin shackle - with a slightly different colour of pin, the paint has changed not the shackle. The Yellow Pin/Brown Pin shackle is not as good as the Black Pin shackle. The colour may have been changed to differentiate it from another company who sell under a, different, Titan brand, registered in certain countries prior to CMP introducing their product.

I do not endorse the Black Pin shackle as I do not believe it as good as the Crosby (Platinum Pin) G209a.

I have tested 3/8th" size 209a shackles and they meet Crosby's specification, slightly exceeding spec. I have tested a significant number of Titan Black Pin shackles, again 3/8th" size and they all failed to meet Titan's (then) specification. Titan (or specifically CMP who own Titan) quibbled with my test procedure (conducted by a reputable test facility on my behalf) and then quietly, and coincidentally , changed their specification and it now accords with my test results. This was no minor change as they had to change the embossing on the bow of the shackle. Some of the old embossed shackles may still be on retailer's shelves

I was left with the feeling their own test procedures were not as rigorous as. maybe, they should be.

There is a cost - 209a shackles cost more than Black Pin shackles and are not as widely distributed outside America.

We use Crosby 209a (or Campbell Orange Pin shackles but these are almost impossible to source outside America). I suggest trying to enlarge the end link to match the clevis pin, rather than buy the Black Pin shackle - that I'm slightly uncomfortable with - but the strength differences are not great, I'm jut twitchy.

A Noelex says the dimension are nominal. I am sure Tecni and Knox will both happily measure the actual pin size of the shackle you want to buy.

There is little point in having a chain that is worth a few hundred pounds and matching it to a shackle that costs peanuts - the strength of the rode is that of the weaker component.

It merits emphasis - the specified strength of a shackle and its WLL is developed in a straight line pull. All shackle makers warn (somewhere in their small print) that if a shackle is loaded at 90 degrees the breaking strength and WLL are reduced by 50%. shackles can lock up in the hole/slot in the anchor shank - the shackle can be loaded at 90 degrees - it does happen - I have a failed shackle that looks (no proof) as if it failed by side loading (the anchor was lost). This is why I would not endorse use of Yellow/Brown Pin shackles - at 50% reduction in strength they are well below the chain that they would be used with.

Jonathan
 
SiteSurfer said:
I'll find out tomorrow if the anchor fits and work backwards from there, the only question left for me then - is the one about the shackle.

I'm going to ask this because I need to be certain. Is the working load stamped on the shackle comprised of a calculation of the weight of the boat + a bit added on for luck or some other figure?

Just wanting to make sure I buy the right damn stuff.
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The shackle designer does not know what teh shackle will be used for but the designer does know what maximum force the shackle has been designed for, that is the WLL (working load limit). The WLL is calculated to take account of the test loads in excess of WLL, inconsistencies in manufacturing tolerances, a bit of fair wear, a bit of corrosion allowance. Basically the shackle is likely good for a lot more than the WLL but you don't know by how much so don't exceed it.

You need to know the WLL of your chain etc and make sure that the shackle is equal or greater. The WLL of your anchoring system is equal to the weakest item in that system: chain, shackle, swivel, eye on the anchor shank, anchor, windlass, cleats, whatever.
 
The main thing to check is that the shackle is as strong as the chain. However, the shackle can be subject to some side loading which does not apply to the chain.

Most shackle manufacturers sugest with a 45° side loading the WLL is 70% of the straight pull and at 90° 50%.

However, as shackles are not expensive the most sensible advice is the corollary of the the anchor advice. Use the strongest shackle that reasonably fits. With G4 or G3 chain there is no need to agonise over small differences. The difference between the Crosby 209A and the Titan black pin for example is only small, so availability, cost etc needs to be factored in.

Fit, so the shackle has little tendency to bind is also very important, perhaps more so than strength.

Most anchors I see have unrated, no name shackles and problems seem rare, so just by using a quality rated shackle you are doing much better than most.
 
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