Anchor chain marking - Base 3 numbering

  • Thread starter Thread starter Anonymous
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If only you and your wife are using the chain do whatever suits you.

For anyone else reading this thread for advice here is my experience.

We use the anchor twice a day most days for six months of the year, and have complete novices handling the chain much of the time. We also night sail and anchor in the dark once a week. We've tried various systems and this is what we have found to be best so far.

We use plastic chain markers - paint didn't last a full season and ties sometimes got caught. We lose several markers each season but as I say we anchor a lot - for swim stops every lunchtime and to Med moor each night. Often the missing ones are found at the bottom of the anchor locker and can be re-used.

We currently use yellow, pale blue, and red markers. The blue can be surprisingly hard to see at night so we are experiementing this year with white markers on one boat.

We use a bit of silicon to help keep them in place.

We have 110metres of 12mm chain marked in groups every 10 metres. The first 10m mark is useful a) to know when to start going astern when Med mooring - you want to know that the anchor has reached the bottom before you start moving back and usually (but not always) the depth is less than 10m, and b) to know when the anchor is nearly up when bringing it in.

(On a smaller boat with less chain 5m marking might be needed but it would be confusing on ours)

We mark alternately with yellow and pale blue.

10m - 1 group of yellow
20m - 2 groups of blue
30m - 3 groups of yellow
40m - 4 groups of blue
50m - 5 groups of yellow

The reason for alternating the colours is that it can be hard to distinguish between 4 groups and 5 groups, for instance, but the colour makes it clear which it is. Also, if we have lost some markers it is still obvious whether the mark is for an even or odd number.

After 5 groups it would be hard to count (and expensive in markers) so we start again, but we introduce red in the middle.

60m - 1 group of blue with red in middle
70m - 2 groups of yellow with red in middle
80m - 3 groups of blue with red in middle
90m - 4 groups of yellow with red in middle
100m - 3 groups of red - you're almost out of chain!

The rules are - yellow is odd numbers, blue is even, count the groups for the number of 10m. Anything with red in it is over 50m (we normally try to put out about 50m when Med mooring in average conditions)

Our students all seem comfortable with this system and pick it up quickly. When we first marked the chain my husband used some strange Royal Navy system and I could never get my head around it. I'm afraid the 'base 3' one seemed too complicated to me as well. /forums/images/graemlins/blush.gif
 
When you say "group" do you mean one plastic marker? How do you determine exactly how much chain is out at a given time if you can't see a marker (which is very probable if you have 10m between markers)? I accept that you don't seem to mind to the nearest 5m (though I differ) but how do you determine whether you have 20m out or 60m out if you cannot see a single marking band?
 
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I will make the card up in Photoshop with a small picture of the windlass and chain and a superimposed example, showing the user how to read the code.

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Working on the KISS principle I decided to use a permanent marker and wrote out our "code" (number & colour of cable ties per 10 metres) on the underside of the anchor locker lid.... fine til the first time we anchored in the dark

You live & learn
 
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Working on the KISS principle I decided to use a permanent marker and wrote out our "code" (number & colour of cable ties per 10 metres) on the underside of the anchor locker lid.... fine til the first time we anchored in the dark

You live & learn


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We too have ours written on the anchor locker lid. Nine times out of ten we anchor in daylight or with enough light to read it, on the tenth time we read it with a little pocket maglite, or even turn the deckflood on which is one of the rare times it gets used! It still counts as KISS I believe.
 
I don't see why you have to use felt tip pens to keep things simple. How would you like it if Raymarine decided to put Dymo labels on its products to 'keep it simple'? No, a bit of time spent making something look professional is not to be despised; on the contrary, it encourages a good attitude and good seamanship.

Felt tip pens to make the labels on a Nauticat? Whatever next? /forums/images/graemlins/shocked.gif

But each to his own, I suppose /forums/images/graemlins/wink.gif
 
A 'group' means that plastic markers are used in several consecutive rings/links of the chain. If you only mark one ring/link it is difficult to see (if there is a twist in the chain as it comes out you could easily miss it). Also, if you only had one link marked and you lost the marker you'd be goosed.

When you buy the plastic markers I think they recommend marking 6 links but we've found you don't need as many as this. I think we normally mark 5 links for the 10m mark, then use groups of 4 marked links. ie: for 20m you mark 4 links, leave 4 links unmarked, then mark another 4 links. When putting out the chain you see two 'groups'. Does this make sense?

We dn't mark every 5m as we haven't found it necessary and on our length of chain would mean loads of markings, but your circumstances might be different.

With our windlass we have found that it takes a slow count of 10 to put out 10m of cable (we say "1 metre out", "2 metres out", "3 metres out". etc.) So if you want to put out 35m rather than 30m you watch for the 30m mark then 'count out' another 5m.

As far as knowing how much chain is out - whoever is on anchor duty should be watching the chain going out (okay we're lucky in that we can usually have two people on the bow, but on deliveries there is just two of us). The anchorperson counts out each 10m going out. It is possible to miss markers, especially at night, but you rarely miss two groups.

We have the markings inside our chain locker too, and also inside the chart table for reference.
 
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