Anchor / Chain / Boat sizing

[laika]

My boat is about 6000kg or 13000lb fully laden and I'm looking at totally revamping my rusty ground tackle system ahead of an open-ended caribbean cruise.

I'm ready to pull the trigger on a 20.5kg mantus to replace the 25lb CQR bower. I'm also looking at a 29.5kg backup/storm mantus as it breaks down neatly, as well as a fortress fx23 to replace my 10lb danforth carried on the stern. My manual Muir Neptune gypsy is stamped to accept 5/16" BBB. Current chain looks to be 9mm as it is ever so slightly larger than 5/16" according to a tape measurer.

According to the rocna knowledge base, my chosen anchors would all fit within the range of G7 8mm chain sizing recommendations. Chain (Rocna Knowledge Base)

I currently have two 100' lengths of long-rusting chain which would be replaced by two 100' lengths of G7 with large end links to accept 10mm high load shackle pins. My stockpile of pristine nylon rode is the one thing in this system that I'm planning to hold onto.

Would much appreciate feedback, good or ill. Not trying to spend a future child's inheritance, but I've got enough money for the best ground tackle system I can fit out.

Many thank yous

[Dsanduril]

Semi-seriously, and also somewhat in jest given how anchor discussions go, why do you think it necessary to nearly double the weight of your bower? Is it that these new generation anchors just don't hold as well, pound-for-pound, as the old standbys?



I do mean that somewhat seriously, do you really need to move up that far in weight to feel comfortable? If so, then proceed, nothing particularly wrong with the overall plan and seems like a quality selection. Test the chain with your gypsy though, unless you want to be replacing that too.

[laika]

Hey, fair enough. It's definitely a comfort thing, but I guess I'd frame the question differently: what am I losing by sizing up?

I don't have any serious gripes with the CQR but 20 lbs more at the bow seems like a small price to pay. I'm young and can easily handle it, especially with the windlass.

According to Mantus, 20.5kg is the "storm" weight recommendation for the anchor on my boat. They recommend the next size down for the working anchor. Based on that, the CQR has always been a bit light.

[Dsanduril]

In that regard you're absolutely right, the 20 pounds is a really small part of the whole deal, and it does seem to help in penetrating the bottom. Just a shift in thinking in all the anchor threads that I find interesting. All the new (and new new) generation anchors that are said to hold so much better also seem to be two to three times the weight of their old counterparts. Makes sense when you factor in the weight of chain, etc. What is a few extra pounds compared to a good night's sleep?

[Jim Cate]

I'm not a proponent of the "storm anchor in the bilge" plan. If y ou are going to buy the bigger Mantus, just use it as your day to day anchor, and forget about the smaller one. But the smaller one seems quite adequate for your boat IMO.

Jim

[laika]

Jim, why don't you like the storm anchor in the bilge? Because it's just not used in practice and quietly collects rust?

What's a better storm management plan? Mangroves? "Y" a couple anchors? Throw the money at better wx collecting and get the hell out of Dodge?

I made it south ahead of Sandy a couple years back, but have always been close to shoreside facilities on the US east coast in the past. A quick haulout was always the gameplan.

Thx

[2kr]

My boat is a 32,000 pound Island Packet 445. I had a CQR that was recommended. It was too light and dragged a few times. I bought a 40KG Rocna. Debated a 32kg. I can drop the Rocna and forget it. I have only had it for a few months. Last week, there was a 40 knot squall, and I didn't move an inch, while one boat provided a great show of saving itself from the mangroves. It looks big on the bow, but I sleep all night

[kas_1611]

When I upgraded our anchor from a 16kg Delta to a 33kg Vulcan I worked on the principle that an anchor that would hold us safe in a storm would also hold us in a breeze. We kept the Delta as a secondary anchor but to be honest I doubt it will ever be used unless something untoward happens to the Vulcan.

The Vulcan by the way fits the bow roller on my Bavaria perfectly and is actually slightly shorter in the shank.

We also upgraded from the "godsknowswhat" 8mm to G70 8mm at the same time. Again working on the theory that it will hold us in a storm etc etc.

Many people have commented on the doubling up from 16 to 33kg but I had always had a suspicion the Delta was small for our 40ft, 11.5ton displacement (note that is not the dry weight) cruiser and from another thread the general consensus was towards the 27kg Mantus or the 33kg Rocna/Vulcan. Neither the Mantus or rollbar Rocna would fit so the Vulcan it was. Now this was for serious storm anchoring up to and including hurricanes.

I agree with Jim that there is no point having a storm anchor sitting in the bilge. You might as well have your storm anchor as your main bower anchor on the strong chain than be buggering about trying to make up an anchor, fasten the chain or rope to it when it can be hanging there all ready to go. Even if you are just stopping for lunch ;-)

Keiron

[evm1024]

In my mind if people are not laughing and pointing at your anchor as they walk by - your anchor is too small.

There is some truth in that statement.

[Cheechako]

I think the 45# anchor is overkill. Your boat is not beamy and only 27 ft. 35# should be more than plenty. Put the savings toward a big Fortress storm anchor if you want.

[w1651]

Go heavy, or go home. IMHO.
Heavy ground tackle, heavy anchors and sleep soundly knowing your going to stay put. Also remember that they do get fouled so have a line attached to drag it up by apart from your anchor rode. I hate it when that happens.

[ranger58sb]

Originally Posted by laika

I don't have any serious gripes with the CQR but 20 lbs more at the bow seems like a small price to pay. I'm young and can easily handle it, especially with the windlass.

According to Mantus, 20.5kg is the "storm" weight recommendation for the anchor on my boat. They recommend the next size down for the working anchor.

If you have a windlass -- and can lift a heavy anchor and the last lengths of chain manually, in a pinch -- I don't see much value in having a "storm" anchor and a lighter "working" anchor.

I'd size my main anchor as a storm anchor -- and the heaviest I could lift manually, if necessary -- and bag the idea of a second "working" anchor altogether. (And a "lunch hook" seems even less useful.)

Another advantage (aside from cost and storage savings) is that you end up with a decent "emergency" anchor on the bow all the time.

And then store a second style of "storm" anchor -- perhaps a dismantle-able design -- too. Along with a second rode.

Having a third anchor on board can of course be useful, as in situations where you may have to abandon one of your primaries for whatever reason... but I wouldn't consider that a "working" anchor and I'd probably (hopefully) never use it. I'd just call it a spare. If I had one in the first place. (Happens I do, of course. Never used it.)

-Chris

[laika]

Thanks for all the feedback, and the bower itself being suitable for storm conditions makes complete sense to me. Perhaps I'm going a bit over the top in trying to plan for cat5 winds with a backup

I have twin bow rollers, but with a heavy duty welded plate in the middle for the forestay/furler extrusion, so anything larger than a dinghy anchor shank won't pass through. I am therefore totally unconstrained by that consideration! But it does mean that I'm always lifting the last few lengths of chain / anchor by hand, and a 45lb anchor seems about the threshold I'd want to deal with on a regular basis.

The current CQR is mounted to welded brackets on the pulpit and according to the specs the mantus shank should also fit (a bigger 55lb would actually fit better), but even if it doesn't I can probably rig up a better placement.

I put a call into IMTRA and hopefully someone will get back to me regarding whether or not 5/16HT will fit my gypsy. Otherwise I'll get a test length. Not the end of the world if it ends up being more 5/16BBB though I suppose. According to the mantus chain sizing chart, I'd be right around the rated WLL for 5/16BBB at 60kts of wind (this apparently doesn't factor in wave action)

It strikes me that downsizing to 7mm G7 and getting more would be the ideal solution for the boat.

Thanks again for all the feedback. It's very helpful.

[Bulawayo]

Originally Posted by laika

Hey, fair enough. It's definitely a comfort thing, but I guess I'd frame the question differently: what am I losing by sizing up?

I don't have any serious gripes with the CQR but 20 lbs more at the bow seems like a small price to pay. I'm young and can easily handle it, especially with the windlass.

According to Mantus, 20.5kg is the "storm" weight recommendation for the anchor on my boat. They recommend the next size down for the working anchor. Based on that, the CQR has always been a bit light.

I am right with you on this - we always, without exception, use an anchor sized for 'storm' conditions. You have no way of knowing for sure when a sudden squall can hit you. I agree this might be more certain in some parts of the world but comfort / peace of mind is hard to put a price on.

[laika]

Originally Posted by ranger42c

If you have a windlass -- and can lift a heavy anchor and the last lengths of chain manually, in a pinch -- I don't see much value in having a "storm" anchor and a lighter "working" anchor.

I'd size my main anchor as a storm anchor -- and the heaviest I could lift manually, if necessary -- and bag the idea of a second "working" anchor altogether. (And a "lunch hook" seems even less useful.)

Another advantage (aside from cost and storage savings) is that you end up with a decent "emergency" anchor on the bow all the time.

And then store a second style of "storm" anchor -- perhaps a dismantle-able design -- too. Along with a second rode.

Having a third anchor on board can of course be useful, as in situations where you may have to abandon one of your primaries for whatever reason... but I wouldn't consider that a "working" anchor and I'd probably (hopefully) never use it. I'd just call it a spare. If I had one in the first place. (Happens I do, of course. Never used it.)

-Chris

I currently have 4 anchors. Two rusty CQRs, a bruce and a danforth. I'm considering keeping the bruce, but part of the allure of the spare mantus is that it breaks down pretty neatly. If I got a much bigger fortress, I'd also keep the 10lb danforth on the stern as an e/kedge anchor.

Space is such a premium though, that it's tempting to get rid of the bruce as well as the cqrs as they take up so much space.

I began cruising on a friend's 40'. Owning a smaller boat is cheaper, but I do find that I'm much more willing to spring for the highest quality, space and power efficient items than I would be otherwise.