Weight Of Ground Tackle.

[powsmias]

Originally Posted by pdenton

I have a Pearson 35, full keel, 13K.
I have 2 NG anchors, 35 pounds each.
I have decided on combined rope and chain rodes about which issue I have no need to discuss.
What I would like to know is what is the combined weight of (chain, rope, bow rollers, winches, winches with batteries in the chain locker, etc.) which is permissible? or even better what weight works for you?
To what extent can the weight in and forward of the chain locker be balanced by weight in the lazarette?
Since I have cleared the deck and thrown away all the old gen anchors, rodes, and fittings I have many options, but obviously the limiting constraint is the total weight.
pdenton

I have the same boat and ran up to defender for 150' of 5/16 g4 have large maxwell windlass and 45 mantus and questioned salesman about the hobby horsing from the weight and wondered if the full keel would eliminate most of it compared to other boats with say fin keels. any thoughts on that theory?

[knockabout]

good ground tackle/trim with beer-wine-h2o-tin food

[Jim Cate]

Originally Posted by powsmias

I have the same boat and ran up to defender for 150' of 5/16 g4 have large maxwell windlass and 45 mantus and questioned salesman about the hobby horsing from the weight and wondered if the full keel would eliminate most of it compared to other boats with say fin keels. any thoughts on that theory?

If anything, the chances are that your full keel hull will be more likely to hobbyhorse than a modern fin keel boat. Two factors that encourage hh are lots of rocker in the fore and aft hull shape and symmetrical waterlines (meaning that equal amounts of water are displaced fore and aft as the boat pitches).

Modern designs, as exemplified by Bennies, Jeanneaus and the ilk have very flat bottoms (little rocker) and the waterlines fine forward and beamy aft. I'm not specifically familiar with your Pearson, but boats of its era mostly are the opposite trend, with considerable rocker, long overhangs and symmetrical waterlines. I think you will see the handwriting on the wall here!

Jim

[rhubstuff]

Sailboat racers want weight low and centered for stability. But on a cruising boat, weight in the ends increases the period of the hull's pitching motion, which makes the boat more comfortable in a heavy sea. So don't be afraid of weight in the bow (or stern) as long as the boat is on her lines.

[peter57]

Originally Posted by Stumble

1) buy a windlass
2) throw away all three anchors (or sell them)
3) buy one 115lb anchor
4) attach the 200' of chain to the new pretty shiny anchor
5) win

You still wind up with less weight in the bow, and have a massively oversized anchor to boot.

I probably wouldn't go with an anchor quite this big... Maybe 100lbs

HI Greg,
45 lb CQR and 100 ft of 1/2" chain will easily hold better than a 65 lb CQR and 300 ft of 3/8" chain. Especially with 180 degree change of direction.
Cheers,
Peter.

[Snowpetrel]

Originally Posted by Stumble

Same here, but the second bower anchor should be disassembled and stored in the bilge. I really like the Fortress for this, because it comes apart, is light for its size, and is really to big physically to be the primary anchor.

I also am in favor of a kedge anchor carried on the dinghy. Basically figure out the size of the kedge you need for the boat, then just use it as the dinghies anchor. Yes it will be oversized for normal operations of the dinghy, but I like big anchors. This system gets you down to 3 on board anchors, saves weight, and provided the maximum holding power possible.(Snip)

:thumbup: Thats an interesting idea about using the dinghy anchor as a kedge, what sort of sizes are you talking about? I like to leave my fx23 fortress assembled and ready to go as a kedge or second anchor in a V, a confuguration that I still find useful for piece of mind in a blow or in poor holding, even though my 60lb manson supreme is by my calculations reasonably 'big' for a lightweight 40 footer.

The funny thing I notice is nearly everyone says they like, or have 'big' anchors, but there seems to be many different ideas of what 'big'really means. Anchor sizing charts aren't any real use in this case as each manufacturer has completely different sizing philosophys, so statements like two sizes above reccomended are pretty meaningless. So how do you define 'big'?

[Stumble]

Originally Posted by Snowpetrel

:thumbup: Thats an interesting idea about using the dinghy anchor as a kedge, what sort of sizes are you talking about? I like to leave my fx23 fortress assembled and ready to go as a kedge or second anchor in a V, a confuguration that I still find useful for piece of mind in a blow or in poor holding, even though my 60lb manson supreme is by my calculations reasonably 'big' for a lightweight 40 footer.

The funny thing I notice is nearly everyone says they like, or have 'big' anchors, but there seems to be many different ideas of what 'big'really means. Anchor sizing charts aren't any real use in this case as each manufacturer has completely different sizing philosophys, so statements like two sizes above reccomended are pretty meaningless. So how do you define 'big'?

My feeling is that when cruising you need to be prepared to ride out a hurricane at anchor, and pray that you never need to. Most anchor recomendations are based on 40-50kn wind speeds. I want an anchor that can hold in 120kn.

1) first define how much weight you want on the bow. This becomes the weight budget
2) define how much chain you need.
3) buy that amount of G70 chain sized to the boat.
4) spend the rest of the weight budget on the anchor reserving enough weight to cover the windlass.

So how big should the anchor be? It just depends on how much weight you can spare. There is almost no downside to a larger anchor, and the excess holding power means you can often shorten the scope and take advantage of tighter anchorages.

Here is what amazes me, when it is common for a 40' boat to carry 150-300 lbs in chain owners worry about if they can justify the 60lb versus the 50lb anchor. It isn't uncommon for a 40' boat to be carrying 400lbs in anchor gear with less than 10% dedicated to the important part, the size of the anchor. I would rather have a 100lb anchor and 'only' carry 150' of chain and 150' of line than a 25lb anchor and 225' of chain. Because holding power goes up as a multiple of anchor weight, much faster than the holding power goes with chain.

Kedge anchors in my view are for comfort and convenance not real holding. So pick one that you can reasonably manhandle from the dink. Exact size is less important that being able to use it comfortably, but the largest that meets this.

The backup anchor, should be roughly the same size as the bower. I.e. Rediculiously oversized compared to manufacturer recomendations.

[UNCIVILIZED]

To the OP, on the question of how much weight to have in your bow. The ideal/obvious answer is easy. But the realistic one is a bit tougher, & the only way to arrive at it is via trying things out. Such as going out on a day with some decent waves in F4-F6, & methodically moving 30kg up to the bow at a time, from the base of the mast, down by the keel. And then in addition to the subjective feel that it generates, track your VMG & SOG differences with each shift in weight.
As the altered pitching doesn't just affect things at deck level, or for the crew, but also has a huge impact on the performance of your sails. SIC.

30kg is enough to be noticeable on a boat of that size, both in her motion, & via how wet things get as you go to windward. And the thing is, is that you don't have to leave the boat rigged one way all of the time. Since there are enough ways to rig quick connect/disconnect fittings so that you can easily add or take off 100' or 100m of chain from any anchor. Such as via a Crosby High Load Shackle which uses a Cross Bolt that's Threaded for a Nut, & also has a Split/Ring Pin that retains the Nut.

It's only one of many examples of connections which require little to no tools in order to easily alter the conposition of one's rode.
And several authors have discussed going through their own similar trial & error process in determining what best to keep up forward in terms of ground tackle, including Annie Hill in Voyaging On A Small Income.


My vote is for the "norm" of one huge primary hook, on mostly chain. With the #2 residing on the bow being a big Fortress or Danforth, on 15-25m of chain, & then rope. With a kedge/#3 being readily available back aft, on a rode much like that of the #2. And your 4th anchor being much like the #1, along with as much chain as possible, all stowed down low in the boat.

All with the caveat that you needn't always have the full length of chain hooked up to the #1. As with a bit of work, it's easy to create a 2ndary chain locker which is back from the bow, with it's own screw on cap on it's deck pipe. But who's purpose is Only to be a ready stowage facility for the rest of the chain for the #1 hook when said chain isn't needed.

Also, for the "kedge', buy one that's as big as one can reasonably handle. So that it's strong enough to pull the mother ship out of a jam when it's called upon to do so. For a 5lb hook in this instance won't do it. And if the kedge is sized thusly, then it makes a decent #2, or #3 when needed. Thus I say buy a decent sized; Danforth, Fortress, or aluminum Spade. And keep it hooked up to a boat length+ of G40 or G7 chain, & 250'+ of serious rode. All stowed together in a kit, & ready to go. Be it for use as the dinghy anchor, or in case you need to use it to correct a "navigational mistake".

Edit: I'm greatly in agreement with Stumble on the sizing of anchors, & where best to put the weight in one's ground tackle system.


Keep in mind too that there are several types of windlasses which don't require mounting them on or near the bow. So that you can move a good bit of weight aft by using such. Between moving the weight of the windlass aft, plus that of the deck reinforcements needed, etc.
This series of Maxwell, for example, which I've posted on for this type of setup, many times in the past. Vertical Windlass Range

And also through proper design, you can use aluminum to build a bow roller that's half the weight of one in bronze or stainless. Which again, pulls an easy 20kg or more off of the bow. Even more with the proper use of G10 or aluminum for backing plates, including building small under deck frames or longitudinals in place of using the sheer size & strength of stainless steel as backing plates. And even those can be judiciously drilled with lightening holes, as can other materials. Much like you see in the booms of some racing boats.

So with some thought towards your anchoring system's design, you can easily pull 40% of the weight of your total anchoring package several feet or more further aft. And or cut a good bit of it's weight out entirely.

PS: With the amount of chain that you're talking about, you won't so much want a windlass, as need one. Even if you shift down go G7 chain.
None of us are immune to getting sick, pulling muscles, or having a smaller skipper or deck ape for the day/week
And even at a beastly 100kg, able to lift triple that, I Want a windlass.

[Olddave]

Worth keeping in mind that putting your anchor and chain in the water will remove all that weight from the bow. Therefore you don't want to have corresponding weight aft that remains on board.
That is going to affect comfort & most boats are anchored most of the time.
Dave

[Snowpetrel]

Originally Posted by Stumble

My feeling is that when cruising you need to be prepared to ride out a hurricane at anchor, and pray that you never need to. Most anchor recomendations are based on 40-50kn wind speeds. I want an anchor that can hold in 120kn.

1) first define how much weight you want on the bow. This becomes the weight budget
2) define how much chain you need.
3) buy that amount of G70 chain sized to the boat.
4) spend the rest of the weight budget on the anchor reserving enough weight to cover the windlass.

So how big should the anchor be? It just depends on how much weight you can spare. There is almost no downside to a larger anchor, and the excess holding power means you can often shorten the scope and take advantage of tighter anchorages.

Here is what amazes me, when it is common for a 40' boat to carry 150-300 lbs in chain owners worry about if they can justify the 60lb versus the 50lb anchor. It isn't uncommon for a 40' boat to be carrying 400lbs in anchor gear with less than 10% dedicated to the important part, the size of the anchor. I would rather have a 100lb anchor and 'only' carry 150' of chain and 150' of line than a 25lb anchor and 225' of chain. Because holding power goes up as a multiple of anchor weight, much faster than the holding power goes with chain.

Kedge anchors in my view are for comfort and convenance not real holding. So pick one that you can reasonably manhandle from the dink. Exact size is less important that being able to use it comfortably, but the largest that meets this.

The backup anchor, should be roughly the same size as the bower. I.e. Rediculiously oversized compared to manufacturer recomendations.

A 100 lb anchor on a normal 40 footer would be very hard to properly set in any harder bottoms. The fluke would often be proud off the surface and more prone to being caught by a loop of chain and unset. Or pulled out in a wind or tide reversal. This is a big negative. It would also be hard to tell if the anchor is set as its deadweight holding alone might be more than a lot of engines can generate in reverse.

A 100lb anchor next gen anchor has a big suface area that would be rather nasty when it pounds through a big seaway. It is too big to easily manhandle, my 66lb bruce is about as heavy as I would want to lug anywhere. So to get it below you would need to use a halyard, assuming it fits down the forward hatch.

Many well set up crusing boats store the chain well aft and low, where its weight has negligible effect on performance and safety, and may even be useful for stability. The huge anchor left on the bow effects both badly. Moment of interia is weight times distance^2 so the anchor right as the bow has a disproportionate effect on pitching, and effects the ability of the bow to rise to a sea or when surfing down a wave, increasing the likelihood of a broach or pitchpole in extreme conditions.

Another concern is the ability to retrieve the anchor in a sticky bottom. Even normal sized anchors can sometimes be very difficult to recover. A supersized anchor could be a nightmare to get back up.

To confidently cope with 120 knots you would need an anchor roughly 4 times heavier than one that can confidently cope with 60 knots. To do this then assuming a 60 lb anchor can happily deal with 60 knots it would need to be nearer 240lb. But the truth of the matter is that bottom type is a much bigger variable than anchor size. In the right bottom their are examples of much smaller anchors coping with cyclones. Surviving a cyclone is a special and rare case. Your normal anchor gear shouldn't really be sized to deal with this alone.

Just to give some comparitive sizes using 100lb for a 40 footer, assuming similar boat types and anchors gives these equivalents weights.

20 footer 25lb
25 footer 39lb
30 footer 59lb
35 footer 76lb
40 footer 100lb
45 footer 126lb
50 footer 156 lb
55 footer 189lb
60 footer 225lb
65 footer 265lb
70 footer 306lb
80 footer 400lb

Compare this to the dashews suggestions

"So, how big should your anchor be? There are no hard rules, except the old laugh rule (the anchor is not big enough until people begin to laugh at you). But in general, assuming you are using one of the new generation hooks like our ROCNA, we’d fit the following to our own boats:

Intermezzo (50-foot ketch) – 100 pounds
Intermezzo ll (62-foot cutter) – 150 pounds
Sundeer (67-foot ketch) – 180 pounds
Beowulf (78-foot ketch) – 225 pounds
Wind Horse (83-foot Unsailboat) – 250 pounds"

http://www.setsail.com/anchors-and-sizing/

Also morgans cloud, another proponent of big anchors has a 120lb spade on a 56 foot boat, roughly equvalent to a 60lb anchor on a 40 footer.

These sizes all pretty well follow the (length on deck(ft)^2)/anchor wt (lb)= around 25 or so.

This rule of thumb gives about a 65 lb anchor for a 40 footer.

20 footer 16lb
25 footer 25lb
30 footer 36lb
35 footer 49lb
40 footer 64lb
45 footer 81lb
50 footer 100 lb
55 footer 121lb
60 footer 144lb
65 footer 169lb
70 footer 196lb
80 footer 256lb

I will also point out Jedi with his 64 footer and a 176lb bruce is roughly the same as a 40 footer with a 68lb Bruce, and he survived a cyclone with that setup, as did Raindog with a 45lb supreme on a 34 footer again roughly equvalent to a 63lb anchor on a 40 footer.

The maths for comparing anchor sizes is simple, windage is roughly proportional to length^2 (assuming similar boat types, as most yachts are) and anchor holding is roughly proportional to anchor weight (assuming similar anchor types). In reality both increase slightly less than these numbers, windage goes up more like ^1.8 to ^1.9 of length due to proportional changes with length, and anchor holding is more like ^0.9 to ^0.95 of weight ( as per the vryhof anchor manual) but both these cancel out pretty well.

[Snowpetrel]

Just as another check of the rule of thumb for anchor scaling. Mirribella V at 254ft originally had a 1320lb bruce, an anchor ratio of 48.8 compared to the dashews value of 25 for a next gen anchor. After she dragged they recalculated her windage and anchor sizes. They went with a 2376lb anchor giving a ratio of 27, much nearer our sweet spot around 25, though being a low holding bruce the anchor could probably be a bit bigger (giving a lower anchor ratio, more around 21)to compare with a next gen anchor. The fact that the scaling rule still gives a sensible answer for such a large vessel shows it is reasonably valid.

Sent from my SM-G930F using Cruisers Sailing Forum mobile app

[ranger58sb]

Originally Posted by Snowpetrel

The funny thing I notice is nearly everyone says they like, or have 'big' anchors, but there seems to be many different ideas of what 'big'really means. Anchor sizing charts aren't any real use in this case as each manufacturer has completely different sizing philosophys, so statements like two sizes above reccomended are pretty meaningless. So how do you define 'big'?

I don't think there's any one answer to that.

Variables include boat size, weight, windage; manufacturer's assessment of holding power (presumably captured in their sizing charts and maybe with info like weight and fluke area, individually modified by boat size/weight/windage info; typical or expected holding ground; make-up and weight of rode; presence (or not) of a windlass of some sort; individual strength (ability to raise the whole thing manually if necessary); and so forth.

I think that means big is relative, might exceed manufacturer's simple or initial recommendations -- or not -- depending on all the rest of the individual variables...

And across anchor types/models, big for one brand/style might (or might not) be heavier and /or larger (or not) compared to another.

IOW, my big might not be the same as your big, nor is there much reason it should be.

-Chris

[Stumble]

Snow,

I agree with you in part. Follow my advice explicitly and you could easily wind up with a 100lb anchor on a 35' boat and that would be downright silly. But just because there are reasonable limits doesn't mean the theory isn't true. By starting with a weight budget you don't need to remove the anchor from the bower ever, though figuring out how to secure it properly in place does need to be figured out. I actually think removing the anchor from the bow is poor seamanship since it eliminates any chance of being able to quickly drop an anchor in case you need to.

As for the boat not being able to fully set the anchor... Well if it's too big for me to set it with the motor, that just means I haven't come close to its full holding power yet. Perhaps the hurricane won't be able to fully set it either, I really don't care. So long as it doesn't move it works for me.

I am happy with Dashew's recomendations on anchors, I am happy to bow to his superior knowledge, and we have pretty much the same idea hen it comes to anchors. Your scaling rule of 25 sounds good to me.

BUT and its a big but, this only applied to SHHP anchors. If you choose to use an anchor type that is proven to have poorer holding power like the old CQR the formula goes right out the window. There is a reason classification societies allow the SHHP anchors to be smaller for the same size ship, and that's because they have been proven to hold better.

[Snowpetrel]

^^ :thumbup: I tend to only pull the anchor off the bow for long ocean passages with a safe runout, and with adequate crew to get it back on the bow reasonably easily for the same reason. Even crossing the Drake (4/5 days) I prefered to leave it in place. I didnt want to be closing the horn in a 50kn westerly without an anchor ready to go.

From memory Beth and Evan starzingers Bruce used came in at about 20. Seems a reasonable number to me for an old school anchor.

[noelex 77]

Originally Posted by Snowpetrel

Compare this to the dashews suggestions

"So, how big should your anchor be? There are no hard rules, except the old laugh rule (the anchor is not big enough until people begin to laugh at you). But in general, assuming you are using one of the new generation hooks like our ROCNA, we’d fit the following to our own boats:

Intermezzo (50-foot ketch) – 100 pounds
Intermezzo ll (62-foot cutter) – 150 pounds
Sundeer (67-foot ketch) – 180 pounds
Beowulf (78-foot ketch) – 225 pounds
Wind Horse (83-foot Unsailboat) – 250 pounds"

SetSail FPB » Blog Archive » More on Anchors and Sizing

Also morgans cloud, another proponent of big anchors has a 120lb spade on a 56 foot boat, roughly equvalent to a 60lb anchor on a 40 footer.

These sizes all pretty well follow the (length on deck(ft)^2)/anchor wt (lb)= around 25 or so.

This rule of thumb gives about a 65 lb anchor for a 40 footer.

Interestingly, like many cruising sailors, Dashew is choosing bigger anchors for his newer boats.

For his 64 foot boat he fitted a 240 lb anchor and for his latest 78 footer fitted a 350 lb anchor. These both correspond to a (length on deck(ft)^2)/anchor wt (lb)= 17. A significant increase in anchor size from 25.


As well as Dashew's famous quote,

"When the fellows in your marina start laughing at the size of your anchor, it's almost big enough."

this is another useful quote from him:

"Since there are no good scientific rules of thumb for choosing anchor sizes, we suggest the following: Look at the average size of anchor in use for boats of your type, and double the size. After doing this, if you think you can swing it, add another 50 percent. "

He has certainly been a champion for "bigger is better" as far as anchors are concerned. Personally, I still think the best advice is to fit the largest anchor your boat can comfortably manage.