Anchor chain questions - new marerials vs old vs old advice

[Chris & Lenore]

We have an Aloha 32 (10,000 displacement). I added an anchor windlass (Maxwell HRC8) that was designed for 5/16 chain and 9/16 line. Unfortunately, when I tried a chain sample I discovered the gypsy was actually for 1/4 chain (my fault for not checking the gypsy part numbers before purchasing my "bargain")...

My plan was to use 75 feet of chain as the boat will eventually see anchoring in Florida and the Bahamas.

So my question is whether to replace the windlass with one that handles 5/16 chain or simply use 1/4 HT chain?

When I look at safe working loads, the newer 1/4 G43 chain has almost 50% greater AWL than the 5/16 BBB that we all used just a few years ago (and many still do).

If the old 5/16 BBB was sufficient for a boat my size then the smaller G43 would still be a significant improvement.

Also, the 1/4 G43 AWL is almost the same as my 9/16 rode, so everything is of similar strength.

The only down side I can think of is the reduction in weight.

Thoughts?

Chris

 

[Stu Jackson]

Re: Anchor chain questions - new marerials vs old vs old adv

Chris, size your entire SYSTEM for the loads you anticipate. 1/4" can sustain a lot.

Anchor System Sizing Tables (Reply #6) & Why Swivels are a bad idea http://c34.org/bbs/index.php/topic,4990.msg30400.html#msg30400

Good luck.

 

[Scott T-Bird]

Re: Anchor chain questions - new marerials vs old vs old adv

I think I would look at the weight reduction as a positive. Why is it a negative? Aside from that, are you thinking of all chain now instead of chain and rope? What size line does the gypsy accommodate?

 

[woodster]

Use the 1/4 inch and 1/2 inch 3 strand nylon line ...you should be ok with that but if you already have the 5/16 chain and larger line weigh the cost of changing either or I have about the same weight boat and am using 1/4 chain and 1/2 inch line

 

[Bob 04 H260]

Chris, I would go with the 1/4" chain and think about a bit bigger anchor. The lighter chain will be easier for the boat to lift off the bottom. I'm using 80 ft of 5/16" chain and feel it is about the minimum I would recommend.
When will you be going us ?
Bob

 

[Chris & Lenore]

Chris, size your entire SYSTEM for the loads you anticipate. 1/4" can sustain a lot. Anchor System Sizing Tables (Reply #6) & Why Swivels are a bad idea http://c34.org/bbs/index.php/topic,4990.msg30400.html#msg30400 Good luck.

Thanks Stu - exactly what I was looking for.

Chris

 

[capta]

The strength of your chain should not be a major factor in choosing chain. It will never be strong enough to take the shock load from the anchor to the boat directly. What you are looking for is the most weight per foot. Often, HT chain has longer links than other grades and therefor less weight per foot.
When you've added nylon line to the equation, either as a snub line, or as part of the rode, then the strength of the chain is even less important.
Spend your money somewhere else; HT chain is a waste of money.
As for changing out windlasses, I'm not familiar with the Maxwells, but it is much easier and cost efficient to just change out the gypsy, if it is possible.

 

[thinwater]

The strength of your chain should not be a major factor in choosing chain. It will never be strong enough to take the shock load from the anchor to the boat directly. What you are looking for is the most weight per foot. Often, HT chain has longer links than other grades and therefor less weight per foot.
When you've added nylon line to the equation, either as a snub line, or as part of the rode, then the strength of the chain is even less important.
Spend your money somewhere else; HT chain is a waste of money.
As for changing out windlasses, I'm not familiar with the Maxwells, but it is much easier and cost efficient to just change out the gypsy, if it is possible.

 

[Ron20324]

Re: Anchor chain questions - new marerials vs old vs old adv

Seeing your windlass handles 1/4 chain, will it even handle the 9/16 line?

 

[capta]

Where'd you find the tiny Coke can? Is that a token from a game? lol

 

[Chris & Lenore]

I had meant changing the gypsy not the entire windlass - but it's $300 to $400.
The windlass seems to work with my 9/16 rode. I've used it half a dozen times with just the line and it works great.
So if looks like I'll go with 75 feet of 1/4 G43 and 100 feet of 9/16 3 strand.
I'll make sure the shackles are matched to the load as well - and - consider a "modern" anchor like the Rocna or Manson.

Thanks everyone for the input - love this board.

Chris

PS Bob - hoping to head south in about three years time, after I get rid of the "day job".

 

[Ron20324]

Re: Anchor chain questions - new marerials vs old vs old adv

You might look at Baconsails.com for a used gypsy.

 

[gettinthere]

I was shocjed at the price of a used gypsy at bacon for my old sl 555 manual.

I would go with more than 75'. I like putting out all chain and not worrying about the rope-chain splice or chafe on rope on the bottom or at the bow. We have 200' of chain. Rarely use more than 125' but nice to have extra.

 

[Bob 04 H260]

PS Bob - hoping to head south in about three years time, after I get rid of the "day job".

Chris, I hope it comes sooner than later for you !

In my limited experience it seems the rode can't be too stiff or too soft or it can give issues with the windlass. Of course the splice is usually a tough spot as well. We use the 35 lb Manson Supreme and it sets well and has never dragged. If I had to do it over again I would buy one size bigger. Our boat displaces 14000 lbs when new and it has additional weight of a 3.5 kW generator, lots of provisions, tools, spares etc. and lots of windage.
I think the Rocna, Mantus and Manson are all pretty close.

Bob

 

[thinwater]

I was shocjed at the price of a used gypsy at bacon for my old sl 555 manual.

I would go with more than 75'. I like putting out all chain and not worrying about the rope-chain splice or chafe on rope on the bottom or at the bow. We have 200' of chain. Rarely use more than 125' but nice to have extra.

Passing the rope/chain splice can be troublesome, and it is nice to be able to anchor on all-chain most of the time. Assuming there is 3 feet of tide, that you have 3 feet of freeboard, and that you want 7:1 scope, 125 feet of chain allows you to anchor in 12 feet of water. 100 feet allows for 8 feet of water, the barest minimum. Thus, 125-150 feet of G43 is a popular compromise. I use 100 feet, but the Chesapeake is shallow, I draw only 3.4 feet, and in retrospect, 125 feet would have been better. But no more than that for me.

 

[edcarter517]

Re: Anchor chain questions - new marerials vs old vs old adv

No consideration should be given to "recommended working load" for anchor chain. This load is taken as a percentage of the breaking strength by some organization (not related to anchoring) for a specific application, such as holding down loads on a truck bed. For this reason only breaking strength should be used for comparing anchor rode. For non-metallic line that should be the weather deteriorated strength of water saturated line. For anchoring you never know the actual load that will occur since there is always a bigger wave or a higher wind gust possible. The test performance of anchors is little help since the holding strength varies by a factor of at least 8 in tests using different methods an in different bottoms. For anchor selection the only criteria should be the known performance of available anchors on similar boats in similar anchoring conditions. In other words, what everybody else seems satisfied with.

 

[thinwater]

No consideration should be given to "recommended working load" for anchor chain. This load is taken as a percentage of the breaking strength by some organization (not related to anchoring) for a specific application, such as holding down loads on a truck bed. For this reason only breaking strength should be used for comparing anchor rode. For non-metallic line that should be the weather deteriorated strength of water saturated line. For anchoring you never know the actual load that will occur since there is always a bigger wave or a higher wind gust possible. The test performance of anchors is little help since the holding strength varies by a factor of at least 8 in tests using different methods an in different bottoms. For anchor selection the only criteria should be the known performance of available anchors on similar boats in similar anchoring conditions. In other words, what everybody else seems satisfied with.

Bot does that make rational decisions seem hopeless! But many of the points are valid.

SWL should be related to both fatigue life and 6 sigma strength (standard deviations below average BS), but there is no formal relation. However, the typical 4-6:1 ratios are generally near the fatigue limit based on published data. The statement that SWL is irrelevant is an over simplification.

Anchor holding force is certainly all over the place. Fascinating subject with very complex answers.

However, there is one simple way to predict the maximum force the rode willl see. It is not too hard to estimate the maximum wind force (many on-line sources). Use a long snubber (at least one boat length) that will be at about 10% of BS a the maximum wind load you will ever see, and it will absorb the waves. The maximum load with be about 2x windload, the fatigue life will be several years of every day anchoring, and the chain and bowsprit will never be challenged ( I tested a bunch of snubbers using a load cell and collected a bunch of cruiser experiences).

The other source of "snubbing" is the anchor moving through the bottom. Even if very well set, when the forces get into tons the anchor will tend to move through the bottom a little. Not dragging in the classic sense, just little steps. A good reason for an anchor with stable drag characteristics. Again, a snubber will stop this "walking," which can happen if the bottom is soft even when the chain does not seem to be snapping super tight.

My personal choise?
* High test chain. The weight will always be better in the anchor than the chain. Notice that I didn't say throw the weight away....
* Large enough anchor. Take some of the weight and money you saved on chain and put it in the hook. Less total $$ and # on the bow, but more holding.
* Use a snubber. Playing "irresistible force meets immovable object" is like the Cold War; no one wins. I like the smoother ride too. If you feel the anchor jerk, you've done something wrong. I never feel it.
* Enough chain to always anchor on all-chain? I think this depends on where you sail. On the Chesapeake I believe 150 feet of chain should be enough for anybody, backed up by rope. But I readily accept that in rocky areas with bad weather more chain makes sense. It's just beyond my experience. It is also true that all of the talk about snubbers obviously changes if you are anchored in 50 feet of water with 500 feet of chain out. Different math.

 

[Charlie Jones s/v Tehani]

I carry 75 feet of 1/4 G4, 22 pound Bruce on a 25 foot boat. I've anchored from the tip of Texas, to Annapolis, and through the Keys and Bahamas. Altogether, over 11,000 miles.

I use a snubber always

I can count on one hand the number of times I've been into the nylon.

 

[Gunni]

The good news is you will now have your second anchor rode and that gives you the ability to split your anchor load across two hooks. When you sense pending weather you can dink out with your second anchor and rest easy. All good.