Anchor-rope -with chain

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supertramp

Senior Member
Joined
Sep 28, 2008
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150
Location
Cubazuela
Vessel Name
" Supertramp "
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Marine Trader Widebody 50 feet
My third anchor are a fortress with 30 meters rope. But i need a short chain. How many meters ?
Norbert
 
Minimum chain for any anchor rode is at least the length of the boat. But remember the longer the better. Chuck
 
Interesting Danforth never recommended a chain on his anchors till the late 60's.Then 5ft or so.

The fortress is a simple copy so the use of chain might be considered optional.

Weather the bottom is mud or coral would be my concern.

FF
 
This was lifted from the Fortress Website
"Anchor Rode.
Use a short length of chain and three strand nylon line. The nylon is very elastic and greatly reduces shock loads on your boat and its anchoring system. The chain protects the line against chafe from the sea bed and also help provide horizontal pull on the anchor when it is initially beginning to set. If you regularly anchor in 25 ft (8 m) of water or less, use 6 ft (2 m) of chain. For greater depths, use 6 ft (2 m) for every 25 ft (8 m) of water depth. (ie: use 24 ft (7 m) of chain if you regularly anchor in 100 ft (30 m) of water)."

Norbert, where in Venezuela do you normally keep your boat?

Steve Willett
Monk 36, Gumbo
Thibodaux, Louisiana
 
Steve my home-base are in Puerto Cabello ( Estado Carabobo )a·m living in Maracay ( Aragua)
Norbert
 
Norbert, on line recommendations aside I would advise at least the length of the boat an absolute minimum for chain. The anchoring system is too important to skimp or take chances. Chuck
 
Around the TexasGulfCoast I normally anchor in less than 25 feet of water and went with the 6 foot recommendation for my FX55. If we did not have such a nasty muddy bottom I would have more, possibly even an all chain rode.
 
All chain is stupid. What good is the boat half of an all chain rode doing ?.



Eric Henning
 
Why is it stupid? For one chain doesnt mold, rot or chafe.
Another reason would be for a remote windlass, the chain falls into an anchor locker better than line. I am sure chain has draw backs like weight and cost but it defiantly has a few advantages.
 
I·m talk about my third anchor . My first anchor had 70 meters chain but the second or third we used when the wind is changing not for the mainline. I must used this anchor with my dinghy- but i think not with 15 meters chain.

Norbert
 
nomadwilly wrote:

All chain is stupid. What good is the boat half of an all chain rode doing ?.
I'd have thought you had more experience than to ask a question like that.* First of all, what do mean by "boat half?"* The chain that's still in the locker?* It's doing exactly what the "boat half" of nylon rode is doing in the locker--- waiting to be deployed if necessary.* Only as Troy pointed out, it's not deteriorating if its wet, it feeds smoothly in and out of the locker*(with the appropriately positioned windlass), and so on.**Now if*you have a planing boat that's a lot of weight to have up front so all-chain may not be the right answer for this type of boat.* But we're talking (I assume) about trawlers here.

And when you deploy more chain out of the locker, what do*you get?* A hell of a lot more weight in the water*to help*reduce the angle of pull on the anchor, to say nothing of simply having more weight on the bottom to help hold the boat in place.* If you deploy more nylon, you get more shock absorbing (which problaby isn't the problem you're trying to solve if your anchor is dragging), but you don't get much in the way of added weight to reduce the angle of pull, which is one of the main elements in keeping your anchor in place.* So you probably have to let out a LOT more nylon to help the anchor stay set than you do chain,which, if you have limited swinging room is a factor that has to be considered.

All chain has advantages, nylon/chain has its advantages.* They both have disadvantages which have to be considered--- type of boat, type of bottoms, the nature of the anchoring situations, etc.* But to say one or the other is stupid is...... well, stupid
smile.gif
 
"And when you deploy more chain out of the locker, what do you get?"

Lots more scrubbing to clean the muck off the chain.

Instead of departure being a 5 min task, its break out the deck wash and spread mud all over.

Scrub, Rinse ,Scrub, Rinse , then scrub the deck as a Bonus Job!

UGH , the stench that is imported below , dead stuff at low tide, is hardly worth a better catinary.

Usually the right sized anchor with a few ft. (on deck carried) chain will do better at anchoring EXCEPT in coral.

FF
 
Marin,
*** There are advantages to*30 to 40 feet of chain but any more and the advantages*aren't even close to the disadvantages of packin all that weight on the boat. Fifteen to 20' of*chain will greatly enhance the performance of most anchors in most anchoring situations by lowering the angle of pull on the anchor. What I*was refering to*in my post was the half of the anchor rode that is*attached to*the boat rather than the half that is attached to the*anchor. The only advantage worth talking about of the boat half is that the skipper of such a boat can claim (rightfully so) that his boat is heavy duty. If I had your boat Marin I'd have 30' of 3/8" chain, your present anchor and 300' of nylon Brait line. And Marin if your boat burned 1gph I'd love to have it. With two 55hp Yanmars and under loaded a bit one could get 2gph*** .. and a ton less weight.

*** Eric Henning*
 
FF wrote:


Usually the right sized anchor with a few ft. (on deck carried) chain will do better at anchoring EXCEPT in coral.
Maybe where you boat.* But not where I boat.* Out here the vast majority of boaters, including the very experienced ones, use all-chain.* The only nylon-chain I ever see is on sailboats and powerboats under 30 feet, and this is because they are either concerned about weight or they don't have the windlass necessary for all chain.

*
 
nomadwilly wrote:


There are advantages to*30 to 40 feet of chain but any more and the advantages*aren't even close to the disadvantages of packin all that weight on the boat..... What I*was refering to*in my post was the half of the anchor rode that is*attached to*the boat rather than the half that is attached to the*anchor.
On the few occasions we've taken the all-chain rode off our boat to install a new windlass or do other work in the chain locker, the difference in the boat's trim and the waterline at the bow was so negligible it was virtually unnoticeable.* But this is a 27,000 pound boat.* A few hundred pounds in the bow makes virtually no difference to it.* In fact the more weight you put in a trawler the better it rides
smile.gif


When you say the half of the rode that is attached to the boat vs the half that is attached to the anchor it demonstrates to me that perhaps you don't understand that the ENTIRE rode that is deployed is playing a role in how well your boat stays put, not just the few feet of chain near the anchor.* And this is the advantage of all-chain, because that heavy "half" attached to the boat plays a major role in how well the anchor sets and stays set.* I've boated on a couple of occasions with friends who have combination rodes.* A couple are sailboaters, one is a powerboater.* And when the wind comes up some, their rode--- out at least to a 7 to 1 ratio--- is more or less straight out.* Which means it's starting to lift that few feet of chain attached to the anchor and raising the angle of pull.* At the same time in the same place in the same wind, our all-chain is angled slightly forward, with a 5 to 1 scope.* Which means all that weight you complain about is doing a geat job of keeping the pull on the anchor low.

If you have a light-weight boat or a planing boat or a boat that's very sensitive to trim (like many sailboats), the weight of all-chain is a definite consideration and in those cases going with a combination rode makes more sense.* But if one's boat can carry it--- which most true (aka heavy) trawlers over 30 feet or so should be able to do--- all-chain should pose no trim issues at all.* I'm talking about a couple hundred feet of chain.* Sure, 500 feet of all-chsin on a 36' boat is going to be overweight and overkill.* We have a 200' combination rode for our stern anchor that can be shackled to our main all-chain rode if we need a lot of rode out, although we haven't had to do this yet.

As to FF's comment about how slow all-chain is to retrieve, that totally depends on the windlass.* Our original windlass was so slow you could probably make new chain as fast as it brought in the old chain.* It finally broke and we put a new Lofrans Tigres on our boat the other year.* This thing brings the chain in so fast it's a bit scary.* And it's a LOT faster than it takes our friends with the combination rodes to get their anchors up, plus we don't have to mess with winding rode around capstan drums or feeding uncooperative line down into the anchor locker.* While researching the type of windlass we wanted to get I read a comment from a charter schooner skipper in the Carribbean* who said thta in addtion to using their Tigres to handle the anchor, they use it to hoist their headsails because it's so fast.* So all-chain or combination is not what determines how fast it comes up, the windlass (or lack of one) does.

We have a very powerful washdown system thanks to a previous owner so the chain goes into the locker clean.* Never had to scrub it with anything, the mud comes right off in the blast of water.* I've noticed that mud and muck come off a chain a lot faster and easier than it comes off of-- and out of-- a nylon rode.* We have friends with stinky anchor lockers--- in all cases it's with a combination rode.

So based on our ten year's experience with all-chain rode, the advice of very experienced acquaintances who've used both combination and all-chain over the years, and what I've observed of people using combination rodes, I would never use a combination rode on our particular type of boat.* But for us weight is not a penalty, and the sometimes tight anchorages we frequent make it more convenient to use a 5 to 1 scope instead of the longer scope needed with a combination rode.

But that's not to say that all-chain is the best answer for someone else's boat.* Like everything to do with anchoring, it comes down to boat type, bottom type, the type of weather one has to deal with, and a kabillion other variables, all of which have to be taken into account.
 
nomadwilly wrote:

With two 55hp Yanmars and under loaded a bit one could get 2gph*** .. and a ton less weight.
Why in God's name would anyone want a pair of little piss-ant 55 hp motors in a boat?* The whole idea behind a "power" boat is power.* That's why they're called that.* Where's the fun in taking a power boat out when all that's attached to the throttles are little play-toy engines?* Our FL120s aren't all that powerful but at least they're BIG.* They look and sound like engines, not like what's on my lawn mower.* I'd be embarrassed to run around in a 36' boat with engines that I could carry in a bucket.

My ideal boat would be 46 feet long with three V-12s in it.* Forty-six feet because that's the size limit of what can be moored to a Washington State park buoy and is as large a boat as I'd want to mainain and operate with two people.* V-12s because..... well, because they're V-12s.** And three of them because that's the most you could fit into a 46 foot boat and have enough room left over to sleep and eat and stuff.

My philosophy with boats is the same as my philosophy with floatplanes--- there's no such thing as too much power.* I like engines.* The bigger and more powerful the better.* If I cared about fuel efficiency I wouldn't be running around in a boat, period.* Given all the other costs associated with boating, fuel will have to get WAY more expensive before its cost becomes a significant enough factor to do something about.

So you can keep all these re-powering schemes using limp-wristed little power plants that sound like a sparrow farting.* Sure, you'll burn hardly any fuel but I can't think of a more boring, uninteresting boat to operate.* Might as well buy a sailboat.* At least then you can get a charge out of working the wind to get five or six knots out of the thing (I used to crew on a racing sailboat so I wil readily acknowledge how exciting a sailboat can be under sail.)

But on my own boat, I want major sh*t going on under the floor.* I want to have to wear ear protection when I do an engine room check.* I keep bees because I like the idea of thousands of critters all working their butts off for me.* I feel the same way about pistons.* The more the merrier.

We bought the slow-ish, low-ish powered boat we did because it was the size we wanted, had the accomodations and layout we wanted, was well-built, and fit our boat purchase budget at the time.** But I don't regard it as ideal by any means.* I would have preferred a lot more power.* Vee engines take up too much space in a boat of this size, but a pair of straight-eights of maybe 400 hp each would have been perfect.* Unfortunately, American Marine wasn't putting anything like that in their boats in the 1970s.* But I can dream.....

Fifty-five horsepower..... Get real!

smile.gif








*
 
"I've boated on a couple of occasions with friends who have combination rodes.* A couple are sailboaters, one is a powerboater.* And when the wind comes up some, their rode--- out at least to a 7 to 1 ratio--- is more or less straight out.* Which means it's starting to lift that few feet of chain attached to the anchor and raising the angle of pull.* At the same time in the same place in the same wind, our all-chain is angled slightly forward, with a 5 to 1 scope."

The angle of the anchor rode is meaningless , the angle of the anchor SHANK is half the key, the other half of the puzzle is SHOCK LOADING , not constant pull.

When it starts to blow there is ZERO stretch in chain , sure its not light to lift off the bottom , but it is metal that doesn't stretch much.

So the shock loading can get really high after the chain is bar tight.

Nylon has great shock absorbing ability , as long as it was selected properly.

Too thin and 100% if the stretch may be loaded , making it as poor as cable or chain..

Too thick and the loads will be too low to get the line to stretch 10%-15% that eases the loads when the gusts blow the bow sideways.

The "ideal" is 1/2 Chain 1/2 rope , but that usually requires far heavier chain than normally found in cruisers.

On our boat most folks would use 3/8 chain . which in most grades BBB? Hi Test ? is pretty weak.

WE* prefer 5 ft of 7/16* or 1/2 in Hi Test and all nylon, the heavier chain* better matches the strength of the 5/8 or 3/4 nylon , the choices.

5ft does lays on deck and works thru the chain stopper .

Our Hyd windlass will only accept wimpy 3/8 chain* which is used in the Bahamas , mostly protected anchorages

"Different ships , different long splices"

But we don't get out of bed in just a thunderstorm.

FF
 
Marian
V12's would be great, have you ever seen a detroit 16v142? talk about a set of twin engines!
What is your cruising speed and fuel burn now?*
 
I am carrying 240 feet of 3/8" chain. Everytime I think of cutting it down and saving some weight, I think about the 3:1 ratio I use and change my mind. There will come a time when rust will win and I will have to replace the chain. The 240 feet of chain fills the locker. How much more room would I need to replace the chain with a nylon rode requireing a 7:1 ratio?
confuse.gif
 
FF wrote:
The angle of the anchor rode is meaningless
Not really, because it indicates the direction of pull on the components still on the bottom.* Yes, the angle of the anchor is what's important to the anchor's ability to hold, but if there is a force starting to lift the anchor shank, depending on the nature of the bottom and the strength of the pulling force, it could start to trip out the anchor.

If one boats in an area where the winds get strong enough to take all the catanary out of an all-chain rode, then an all-chain rode is not the right sort of rode to be using.* In this area, under most conditions most boaters up here experience, we never get weather conditions nearly that bad, or if we're going to there are plenty of protected places to get to in a relatively short time.* Of much more concern is the limited room in many anchorages either by geography or number of boats.* So being able to use a shorter scope is a big advantage much of the time.

*
 
troy994719 wrote:

Marian
V12's would be great, have you ever seen a detroit 16v142? talk about a set of twin engines!
What is your cruising speed and fuel burn now?*
With the two FL120s at about 1600 rpm (SW tachs are notoriously inaccurate) we get about 8 knots and burn about 5 gph.* We used to get about a quarter knot more before we had the props pitched down last year, but even though our speed as been reduced a bit, our EGT came down a bit so the engines aren't working quite as hard and our fuel burn came down a bit.* Probably a wash between the reduced fuel consumption and the reduced speed, but fuel consumption and cruise speed were not the reasons we had the props repitched.

I don't like 8 knots as a cruise speed. I would prefer 12 to 14.** I don't like a cruise speed of 110 mph in the Beaver either.* I'd prefer 200.* But you gets what you gets, right?

*
 
I was curious what a similar size trawler*would do with the bigger engines, i have twin lehman 80's and run about 6.5 knots at 1600 RPM. *
 
To my knowledge (and I could well be wrong) the largest engine the manufacturer put in the GB36 was the 210 Cummins (some installations may have used the 220 hp Cummins). Either one or two of them. The '91 GB36 we chartered before we got our own had a single 210 in it. At 2000 rpm, it cruised a smidge over 8 knots. I have no idea what the fuel burn was.

Of course the GB hull can be driven much faster than this, but its efficiency is kind of sucky. Fuel consumption on a high-power GB42 twin goes from about 6-7 gph at about 9 knots to some 23 gph at about 14 knots.
 
Troy: My boat is a Halvorsen 32 Gourmet Cruiser....same exact hull as the IG 32.

Here is a chart I made up after several fill ups at the pump. The gph is determined by a FloScan that has been adjusted to reflect actual gallons taken on. Speed was determined at slack tide, two directions and with GPS.* After achieving hull speed (roughly 7.3kts) all I do is push more water!
 

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Permission to brag captain?

Since the thread has morphed into a fuel economy discussion, my boat is full displacement, loa 39' with a w/l of 35.5', beam of 10 6' and displacement of 20000lb.

power is a single cummins 210 of which I typically use 40hp to cruise.

1500 rpm = 7.5 knots and 1.4 gph

1800 rpm = 9 knots and 1.8 gph

I can burn more fuel if necessary (rapids and such), but try not to.

Just cuz you have the power doesnt mean you have to use it.

Although when I run it up to WOT of 2500 it will make a mini-tsunami which with a sharp port turn, can make a nice present for the bayliner who just past me going 18knts in the narrow channel to steal the prime anchorage in the cove just ahead. ;)

I suspect my motor will run a LONG time before needing a rebuild if you factor life of a diesel by total gallons used as opposed to enging hours.

your 'mileage' may vary
 
Hey Marin,
**** My wife in the other room wanted to know what I was laughing about. Well I guess you wouldn't be thrilled w my 37hp Willard. Don't even need ear plugs w the engine hatches open. Did they ever make an inline 8-71 DD ?. If I could afford it I'd have a boat w large twin DDs. Thanks for the response on anchor rodes. I don't agree w much of your reasoning but I will admit that all chain rode makes a great reduction in swinging room** .. a very good asset in our part of the sea. Does anyone know* .. is 1/4" chain as strong as 5/8 nylon?. I sent my super anchor**(XYZ) out to my welder for mods. I just talked to a fisherman at the dock about his 96lb Forfjord on a 34' boat and he said his 65lb Forfjord draged in a 65mph wind so he got the 96lb model. Think he has 1/2" chain (or larger) w an on deck hyd winch. Those fishermen must be related to you Marin.
*** Shanafelt,
****Your boat is the same beam as my 30' Willard but almost 10' longer. I love long narrow boats and so does FF.
*** Walt,
*** You're going 1/2 knot faster than me at 1400 rpm.

***** Eric Henning

****
 
Eric---

So far as I can determine Detroit diesels were available in in-line configurations of one, two, three, four, and six cylinders and Vee configurations of six, eight, twelve, sixteen, and twenty-four cylinders. No straight eights.

As I see it the primary advantages of all-chain rode are weight and resistance to damage, the primary advantages of nylon rode are light weight and shock absorbing. So which one a boater elects to use should depend on which one's advantages are best suited for the kinds of anchoring situations the boater is likely to encounter. Like most of the boaters we know in this area, I want a lot of weight in the water down as low as possible and I want the ability to anchor with a relatively short scope. And I don't want to mess around with a kellet. The chances of my needing to anchor under conditions that would take all the catenary out of the chain are remote to zero, so I'm not worried about chain's lack of shock absorbing.

I've met some sailboaters who have done a lot of cruising in the southwest Pacific. They said they often anchored in very exposed anchorages, used tandem anchors, and let out a ton of rode to deal with the winds and waves. For them, shock absorbing (and less weight) were major considerations. All chain would have been the wrong choice.
 
"How much more room would I need to replace the chain with a nylon rode requireing a 7:1 ratio?confuse"

Depends if you are willing to spend the bucks for the newer style line that is very compact when dumped down a hole.

Our solution is to coil the nylon rode on deck in around , which is flipped into a figure 8 .

It sits on the deck with no hassles and the anchor is ready for INSTANT deployment ,

no hoping the chain pile didn't tumble or the 3 plait didn't hockle below in the locker.

FF
 
If you're trying to keep the anchor shank down just put a 100# lead ball on the end of the anchor shank. 1st the anchor would stay down, 2nd the rode would weigh less than all chain and 3rd the all nylon rode would have maximum shock absorbing ability. Yea** .. thats what I thought on the DDs. Marin* .. you don't need to worry about shock absorbing ability w your all chain rode. the chain, under load will lay in a 1/4 circle and have huge shock absorbing capicity unless it's pulled straight out and an all chain rode straight out means you've got much worse troubles than lack of shock absorbsion.

FF,
**** There is a boat here in Thorne Bay that does that. He has two posts about 1" in dia and 12 - 14" high. He lays the rode down in a figure eight around the posts port and starboard.**Don't know what*happens*when the bow goes weightless on the nasty?

**** Eric Henning
 
This is a timely discussion for me as I just spent a week with a student who insisted that when he switched to all chain rode his anchor failed to hold any better and actually held worse, and now he uses two anchors. Needless to say, we had quite the discussion about what may be wrong with his setup. Never the less, all the discussion so far about the disadvantages of all chain rode has failed to mention one critical fact. A properly designed and deployed snubber will eliminate the problem of a lack of shock absorbing stretch provided with line. I use one every time I anchor, even in zero winds, since it also prevents the chain from transmitting the noise of every little rock it drags across all night. Using all chain has several advantages for us. First, most anchorages here are pretty deep, and we routinely anchor in 50 to 60 feet, and often times can't find water that shallow. All chain increases our holding power, allowing shorter scope than using a combination of chain and line. Sure, we could send down a sentinal, or kellet, (a weight attached mid way down the line) to increase holding power, but that's just too much work unless we are expecting really bad conditions. Our chain gipsey is designed for all chain, and most combination chain / rode ones I have seen don't do too well with line, and the line tends to override on its self. We carry just over 300 feet of 3/8 chain, with an 80 lb Delta fast set anchor. In hundreds of anchorages, only once has it failed to set on the first try, and believe me I back down on it HARD each time I set it, since I don't enjoy getting up in the middle of the night to check a draging anchor. I often times put it all out even in shallow water, since I don't see any disadvantage to doing so, except in a crowded anchorage (almost never a problem here) It takes no more effort to get it all back than it does to get only half of it back. If my button pushing finger gets tired, I simply switch fingers. Our set-up has held us secure in sustained 65 knot winds (for almost two days) and didn't drag an inch. With a lighter rode, no doubt I would have felt even less secure. So, for us, an all chain rode with a snubber will always be the answer. If I could hoist an even bigger anchor, I'd have that too, but at the time I bought it, the 80lb Fast set was the biggest readily available. Actually, I'm thinking of adding even more chain, but don't know how to splice it to insure equal tensle strength of the original chain the splice and the new chain, and still go around my gipsy. Anyone know the answer?

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