How much spaced required to hold 3/8" Acco G-4 chain

[sailorjohn99]

I am interested in buying 3/8" Acco G-4 chain, but I am concerned about the amount of storage space in my chain locker. (I am considering buying either 200 feet or 300 feet).

Does anyone have an estimate of the amount of space this chain requires?

Thanks!

John

[GordMay]

Greetings and welcome aboard the CF, John.

The volume required for 300 Ft of 3/8" chain is about 5.9 cubic feet
➥ http://www.anyboat.com/webpages/anchor.htm

[UNCIVILIZED]

Are you trying to figure out in terms of how much space is needed if it's falling freely, & stacking itself, or if you pack it into a space by hand, so that it takes up as little space as possible? As there's a vast difference between the two, with the former usually being 2.5-3x the latter. And it also depends upon the shape of the space, & whether it's accessable from above, or from the side only.

[sailorjohn99]

Originally Posted by UNCIVILIZED

Are you trying to figure out in terms of how much space is needed if it's falling freely, & stacking itself, or if you pack it into a space by hand, so that it takes up as little space as possible? As there's a vast difference between the two, with the former usually being 2.5-3x the latter. And it also depends upon the shape of the space, & whether it's accessable from above, or from the side only.

Nope. Just wanted the square footage. I'll figure the rest out.

Thanks!

[sailorjohn99]

Originally Posted by GordMay

Greetings and welcome aboard the CF, John.

The volume required for 300 Ft of 3/8" chain is about 5.9 cubic feet
➥ Anchor Chain Storage Calculator

Perfect. Thank you, Gord.

[captstu]

What size is your boat? I downsize my chain from 3/8to 5/16 on my 45 foot catamaran. Most of the time was OK but it stretched in a category four hurricane. I was the only boat left in the anchorage since most boats broke loose and ran aground.

On my current 25 foot powerboat I downsized from 5/16 to 1/4 HT chain. It should be good to about 100 kn. At that point

Depending on your sailing and cruising area you may be able to safely downsize.

[onavegador]

Hi Gord,

I also tried find out the anchor locker size for 300 foot of 10 mm chain. But receive results what cannot be true. May it bee that I do not anderstand the expression chain link (a link on a 10mm dia chain mesures 10x30x28mm ISO).
One result was 4250 cubic feet the other, I understood, less than 1 cubic foot).

So I like to ask you what I have to enter under chainlinks decimal? Thank you so much.

And to Stuart what you wrote is against all I learned in Europe about anchoring. 1st) I decided to use galvanized chain instead of stainless steel because stainless steel chain is lighter than galvanized chain. My 40foot catamaran was equipped with 300foot 8mm chain and 32kg (70,5 lbs) Bugel anchor but after some experience with slipping anchor and when I have seen that on other boats with heavier chain had no problems, I changed to 10mm also 300 foot in length. With that equipment I had no more issues with slipping anchor (o.k. one or two times around Ushuaia with Kelp). Strongest wind I had on anchor was in the Falkland Island with severe gusts of over 55 Knots and later near Brisbane during a Thunderstorm with so called devasting winds of about 55 Knots in gusts.
I also learned from a french graduated engineer that the weight of chain is more important as the weight of the anchor.

But Your answer is interesting to read, may be your boat was and is more aerodynamic than my cat was.

Fair winds
James

[Cheechako]

Let's see... estimating from history I'm guess two 5 gallon buckets for 200 feet maybe...

[groundtackle]

"I decided to use galvanized chain instead of stainless steel because stainless steel chain is lighter than galvanized chain"
Don't intend to hijack your thread, just curious about this comment.
"lighter" meaning "not as strong"?
ce

[antoha]

One-vega, a foot is about 30 cm = 0.3 m; so 40 ft^3 ~ 1m^3, which is 1 ton of water. So this 4200 cu ft > 100 ton of water sounds very strange, that's likely bigger than your boat's displacement. Maybe those were cubic inches?

[Cheechako]

Originally Posted by groundtackle

"I decided to use galvanized chain instead of stainless steel because stainless steel chain is lighter than galvanized chain"
Don't intend to hijack your thread, just curious about this comment.
"lighter" meaning "not as strong"?
ce

Never thought of it before but I suppose SS may be a bit lighter, as galvanizing is heavy due to the lead content right? Although... hmmm... SS may be heavier par on par... about 1.5-2% IIRC.

[groundtackle]

I've be instructed to do my chores so got to go, my point was..
weight- Cats (assume it is one) should always be on a diet and if s.s. was lighter (not a lot but could be 30-50 lbs) why did you go galv?
Strength- against mid grade 40-43 galv is significantly stronger. That makes sense.
Cost- galv is seriously lighter. That makes cents.
ce

[thinwater]

Originally Posted by groundtackle

"I decided to use galvanized chain instead of stainless steel because stainless steel chain is lighter than galvanized chain"
Don't intend to hijack your thread, just curious about this comment.
"lighter" meaning "not as strong"?
ce

a. G4 is lighter than G3 stainless, for equal weight.

b. Given his comments that chain weight is more important than anchor weight, I wouldn't analyze the comments. I do wonder about the graduate engineer.

c. Anytime an adamant statement is qualified with vague exceptions, it is no longer an adamant statement. For example, the chain is now heavier, which certainly helps some small amount, but there is no proof or evidence that less money and less weight for a better anchor would not have been even better. He added 150 pounds of chain, but switching to a 10# heavier modern anchor would very likely have done much more, for less money and 140# less in the bow. So the example provides no new information.

[Jim Cate]

a. G4 is lighter than G3 stainless, for equal weight.

???? Don't quite get this...

Jim

[captstu]

John,

Anchoring is more of a religious issue than an absolute engineering question - although I am, by trade, an engineer, most of what I learned was gained by asking the skippers in the anchorage what they did - if they were among those that did NOT drag during a blow.

Absolute strength per unit weight is higher for G4 galvanized similar weight stainless. But, that is only part of the equation. I sized my ground tackle for the highest expected load I would expect to "live through" on my 43' Voyage catamaran. That got me 5/16 HT chain (G4), a 25 kg Bruce and - the critical part - a 12 kg Fortress. I had sufficient chain, 50 meters, for my usual anchoring depth of 3 to 4 meters.

The critical item is the Bruce was shackled directly to the chain and 2 meters of chain were shackled to the "trip point", the hole in the front of the anchor intended to remove the anchor when set very deeply. The other end of the short chain was shackled to the Fortress - two anchors in a line with the Fortress being deployed first then the Bruce being set on a 10:1 scope for heavy weather.

Now, the boat end of the chain was shackled to a twin 6 meter bridle - in the form of a V with the chain effectively shackled to each catamaran bow just above the water line. The line was 5/8" (sorry, I don't know the metric equivalent offhand) and connected to the chain with a KONG chain grabber.

In heavy weather, a second 3/4" bridle was "bent" onto the chain with a rolling hitch, just above the KONG. both the KONG and the rolling hitch were IN THE WATER directly in front of the boat under normal conditions - up to about 20 knots.

Everything worked for several years - we never dragged, not even once. Our normal anchoring procedure was to sail into our chosen anchorage - well away from other boats, depoy the Fortress, depoy the chain and Bruce, count to 10 and hold on. The boat stopped instantly, turned into the wind and we released the brake on the main. We usually furled the jib as we entered the anchorage.

The storm, Hurricane Wilma - my 5th storm since I bought the boat - was predicted so severe that I left the boat and went to shelter inland. the near eye went over the anchorage, breaking nearly every other boat loose and putting them aground. My boat ran down the chain, over the anchor setup, and stopped SUDDENLY when it got to the other end of the setup.

Both bridles snapped. The anchor pulled out of its platform, OEM plus a second layer of reenforcing I added when I down sized the chain. One of my previous encounters had a man, much more experienced than I was, tell me to be sure and tie a large overhand knot in the chain - that knot jammed in the hawse pipe - clearly had it of not jammed, the chain attached to a factory provided hard point with a shackle would have broken the hard point and the boat would have joined the others on the beach - probably a total loss.

In addition to the minor damage of lines and windless shelves, the CHAIN STRETCHED since it was stressed well above its safe working load -- but not to the breaking point.

Stainless chain would have snapped - the safe working load is, in some chains, similar than that of galvanized - but the breaking load is not as high. Galvanized stretches - and becomes useless while saving the boat - where stainless just snaps.

My experience indicates that Bahamian anchoring is not of any value in an ultimate storm - only tandem anchors help more than one anchor - in my case, the Fortress was twisted to a potato chip as it held in place for the time it took the Bruce to reset. When I went out to the boat, I dived the ground tackle and the wire tie I put 2 meters from the anchor (so I could know when the setup was about to lift out of the water so I could go and retrieve the Fortress) was buried. The Bruce was 2 meters into the mud - it was undamaged. Fortress replaced the damaged flukes at no charge.

Don't buy excessive size chain - 5/16" is sufficient for a 43' catamaran if you don't mind replacing it after a 100 year storm. Don't use stainless steel chain or shackles unless the shackles are drop forged by a reliable supplier (Wichard or Kong)

There isn't any way to absorb the force required to break a 5/16" chain on most production boats - and larger chains are just more weight without more benefit.

Most of all, if you doubt your 5/16" chain is strong enough for the expected storm, seek shelter on land!

Good luck.