Length of Chain

[Searanger50]

hi again,
Thanks. I was working on between 8:1 and 10:1 but am unsure of the maximum depths I am likely to need to anchor in. We (My wife Sandy and I) are planning to leave the UK in 20 months time for as very slow circumnavigation / exploring cruise taking in the Med, W.Africa as far as Gambia, Caribbean, S.Am as far as Rio, the Pacific, N.Zealand, Australia, Far East and back (over about 10 years if health allows). We are currrently fitting out our boat and would like to leave with all bigger purchases and jobs down before we go as I will then be retired and money will be needed for cruising, maintenance and repairs.

[Dockhead]

Originally Posted by jackdale

But stumbles idea is among the best.

+1

Never thought of it -- ingenious in its simplicity A really good method. Think I will try it myself.

[Dockhead]

Originally Posted by Greg Fil

You are all good. And I like your ideas. However, I am talking about situation when:
1. It's not your boat.
2. Anchor chain / line is not marked.

Thank you everybody for such a quick reply.

I marked my chain and then idiotically forgot the code. So I have been judging by the volume of chain left in the chain locker -- with practice, you get a pretty good feel for it.

That's assuming you can directly observe the pile of chain in the locker. If you can't, then you'll have to think of something else.

[Seaworthy Lass]

Originally Posted by Searanger50

hi again,
Thanks. I was working on between 8:1 and 10:1 but am unsure of the maximum depths I am likely to need to anchor in. We (My wife Sandy and I) are planning to leave the UK in 20 months time for as very slow circumnavigation / exploring cruise taking in the Med, W.Africa as far as Gambia, Caribbean, S.Am as far as Rio, the Pacific, N.Zealand, Australia, Far East and back (over about 10 years if health allows). We are currrently fitting out our boat and would like to leave with all bigger purchases and jobs down before we go as I will then be retired and money will be needed for cruising, maintenance and repairs.

When calculating scope, people often forget to take the vertical distance from the water to the bow roller into account (about 1.5m in our case).
So 8:1 with 100m of chain means maximum depth of 10.5m, not 12m for us.

In northern Australia we commonly needed to anchor in 15m (so 100m would give only 6:1) and the same applied in Tonga.

Here in the Aegean we are usually in water less than 10m, so we usually use less than 50m of our chain, but in summer it is nice to be able to anchor deeper a little further out to avoid the crowds, and if we want 10:1 when 50+ knots is forecast (usually a couple of times a year) 100m of chain still restricts us to anchoring in 8.5m or less.

[Doug Brown]

Ask the charter company HOW MUCH chain is on the rode. If you are in 30-ft or less of water and there is 150-ft of chain, but it ALL out - each and every time you anchor.

If there is less chain, but it all out AND put out some of the nylon rode too. If there is more chain, put out a max of 180-ft of chain.

If you are away from the boat and a 35+ knot squall comes through the anchorage, you won't have to worry about finding the boat washed up on a rock or beach when you return.

[Seaworthy Lass]

Originally Posted by Doug Brown

Ask the charter company HOW MUCH chain is on the rode. If you are in 30-ft or less of water and there is 150-ft of chain, but it ALL out - each and every time you anchor.

If there is less chain, but it all out AND put out some of the nylon rode too. If there is more chain, put out a max of 180-ft of chain.

If you are away from the boat and a 35+ knot squall comes through the anchorage, you won't have to worry about finding the boat washed up on a rock or beach when you return.

The only drawback with putting it all out irrespective of depth, is that you will swing very differently to the other boats around you and this will be significant in a crowded anchorage. I remember 100+ masts in Lakki (Paxos) one August and the wind swirling in all directions. Someone with all their chain out there would have created mayhem!!!!

[Bluewaters2812]

Originally Posted by Stumble

An afternoon with two cans of spray paint tied up along a shore pier and the chain is vividly marked, and will last for years. Just alternate the colors every 25 foot, and count the number of color changes as it spools out.

A good idea. Would yellow and white be good colours to use?

[Searanger50]

Would there be enough contrast in poor / torchlight??

[Bluewaters2812]

Perhaps orange and white would be better than yellow and white?

[Amnesia II]

People, 100m of 3/8" chain is VERY heavy, in the bows of a 36 foot boat while sailing in any sort of lumpy sea. In my opinion talking 8:1 & 10:1 is enormous ratios to apply when anchoring, normally 4 or 5:1 is very acceptable. Don't forget too a well sized anchor for your boat, equally important as amount of chain.

[Seaworthy Lass]

I have found these little soft chain markers to be excellent. Used them for the first time in April and despite anchoring each day we have only lost one. As we anchor all the time, for several years the paint we used didn't last much more than a season (a hassle as we only haul out every two years).

We are using the snooker system for colour so it is easy to remember.
Apply lots as they are easy to miss as the chain is running out and it gives some redundancy if any a lost.

Our marking system:
10m white x 5
20m yellow x 5
30m green x 5
40m blue x 5
50m pink x 5
60m white x 10
70m yellow x 10
80m green x 10
90m blue x 10
100m pink x 10 (useful to have this one to know when the limit will be reached, we have about 105m)

It was a bit of an effort squeezing them into the links (water helped). Just in case these markers proved to be unreliable, I also tied on some little bits of kevlar string so they can be felt at night (these pass easily around the winch). Both types of markers are lasting brilliantly.

Photo shows what we are using and its size relative to a phone:

[Bluewaters2812]

[QUOTE=Seaworthy Lass;1065686]I have found these little soft chain markers to be excellent. ...

100m pink x 10 (useful to have this one to know when the limit will be reached, we have about 105m)


Now those seem like handy little markers. Where are they available and how much do they cost?

[Seaworthy Lass]

Originally Posted by Bluewaters2812

Now those seem like handy little markers. Where are they available and how much do they cost?

Bought them from two chandleries in Leros (Greece) in March 2012. They come in different sizes (from memory for 8, 10 and 12 mm chain at least). Each packet has about 10 of the one colour. Sorry, I cant remember the cost (4€ ???).

I think these are the ones I bought:
http://www.marinechandlery.com/produ...d-colours.aspx

They are a soft plastic. Tried the hard plastic ones that snap together when fitting them in, but they were useless - didn't last long at all.

[carstenb]

Hi Amnesia,

Scope of 8:1 or longer is for heavy conditions. Peter Smith (Catenary & Scope In Anchor Rode: Anchor Systems For Small Boats), inventor of the Rocna anchor, shows through simulations that catenary vanishes as winds increase above 40 knots. Obviously, once the catenary is gone, scope has little impact (although carrying scope to the extreme, say 50 or 100:1 will give a pull angle closer to the seabed). In fact, increasing scope beyond 8:1 becomes a situation with decreasing returns.

So yes, 100 meters of chain is indeed heavy, and under "normal" conditions, 5:1 will suffice, you can never be sure when the wind will blow up. 40 knots is "only" a gale, albeit a strong one. Gales, are quite common, at least here in the Baltic.

If you have an anchor winch which will pull both, a solution is to go half chain, half nylon rope. This has several advantages: lighter, and you get a built-in snubber. If you are anchoring on rock or coral, however, the rope will chafe and may break.

Given the choice, I'll take chain.

[Bluewaters2812]

Originally Posted by Seaworthy Lass

Bought them from two chandleries in Leros (Greece) in March 2012. They come in different sizes (from memory for 8, 10 and 12 mm chain at least). Each packet has about 10 of the one colour. Sorry, I cant remember the cost (4€ ???).

I think these are the ones I bought:
Chain Marker (Pack of 10 assorted colours) - Accessories - Marine Chandlery - Marine Supplies and Sailing Products

They are a soft plastic. Tried the hard plastic ones that snap together when fitting them in, but they were useless - didn't last long at all.

Very useful info, thanks SL. Cost is not much too. I am sure the US and Carib has supplies of these too. Makes sense to me to use these as they won't snag the rollers and replacement of occasional lost ones is less hassle than getting it all out and using spray-paint?