Another suggestion for anchor chain marking

[Danny Jo]

Two very helpful threads on this topic recently, but each method has certain disadvantages. Lemain's thread on coloured markers and TCM's on painted chain suggest that one needs to judge them by a number of criteria:

1. Utility: code must is easy to understand and decode, and should ideally be "intuitive".

2. Direction independence: code, if used, must read the same in both directions - i.e. BWW means the same as WWB.

3. Safety: markers must not cause injury or snagging.

4. Error detection: loss of marker, or its obscuring by mud or seaweed, should be obvious.

5. Low light readability: markers must be distinguishable even when there is so little light that colour discrimination is impossible (but where black and white vision is still possible).

6. Cost: system must be economical and practicable.

TCM's chain painting system scores well on 1-3, but fails to satisfy 5 and, for me at least, 6. Where the hell am I going to find space to lay out 60 metres of chain for a week while the Hammerite dries, let alone a surface that will tolerate Hammerite and release the chain when its dry? And don't say "outside, on sheets of polythene" - it's far to windy round here, and dry days are reserved for work on the hull and deck.

Many of the chain marking systems discussed on Lemain's thread fail to satisfy 1, 2 or 4. Is this red green green, or green green red? Is this the twenty metre mark (two reds), or the thirty metre mark that has lost one of its markers? Remind me, is this the first red red red, or the second?

I am going to be lined up and shot as a total nerd, I know, but here is my suggestion for a 60 metre length of chain.

Markers can painted links or chain inserts with a dob of sealant (polyiforgetwhich, not silicone), in three colours that can be distinguished in low light conditions - e.g. yellow (Y) green (G) and black (B).

Mtrs Code
05 = YYY
10 = GYY
15 = YGY
20 = GGY
25 = GYG
30 = GGG
35 = YBY
40 = BYY
45 = BYB
50 = BBY
55 = BBB

Excepting the 30 mark, all symmetrical codes are 5's. If there is one green in it you have at least 10 metres; two greens, at least 20; one black, at least 35; two or more blacks, at least 50.

Well I can remember it, anyway.

Mark

 

[sarabande]

I can't fault the basis on which you judge the effectiveness of marking the chains, nor the choice of colours (except perhaps - what about the various types of colour-blindness. Isn't there one where yellows and green both go murky ?)

But... as humans we are programmed to use the decimal system, and your permutations of three colours does not, with respect, seem to meet the intuitive criterion.

What about the following (which assumes that chains are always in the same orientation, i.e, the anchor end doesn't get swapped for the bitter end. Perhaps a risk ?)

Yellow is a 5 marker
Green is a 10 marker
Black is a 20 marker.

So

5 Y
10 G
15 GY
20 B
25 BY
30 BG
35 BGY
40 BB
45 BBY
50 BBG
55 BBGY
60 BBB


The process of identifying how much chain is out relies on crew knowing only that

5 = Y
10 = G
20 = B

and being able to add up !

Consistency and correlation of colour to a given length is, I submit, key to marking and interpretation.

 

[cliff]

Are you for real or only a troll?
--------------------

"Artificial intelligence is no match for natural stupidity"
sailroom <span style="color:red">The place to auction your previously loved boatie bits</span>

 

[LadyInBed]

Whatever marking system you use it is never idiot proof

 

[Poignard]

I don't understand why you need to mark your cable every 5 metres, every 10 metres [or 5 fathoms for Imperialists] seems quite adequate to me and this would halve the work of marking it.

 

[Danny Jo]

[ QUOTE ]
what about the various types of colour-blindness. Isn't there one where yellows and green both go murky

[/ QUOTE ] The yellow was intended to be light, and the green in the middle of the grey scale, but point taken. Another choice could be white, orange, black. [ QUOTE ]
as humans we are programmed to use the decimal system, and your permutations of three colours does not, with respect, seem to meet the intuitive criterion.

[/ QUOTE ] On reflection, I think you are right. I looked at four coding systems, including the one you outlined, and got rather carried away with error-proofing. The triplets are good from this point of view because it is immediately obvious when one is missing. But having looked at the cost of the markers available, I've decided to use bands of paint, so I'm inclined to follow your suggestion. Thank you.

Mark

 

[Danny Jo]

Me, a troll? Perish the thought.

No, not a troll, just too obsessional for my own good. The idea seems terrific when first dreamt up, but needed to be set in the harsh winds of Scuttlebutt criticism to see whether it would fly or get torn to shreds. Thank you for indulging me.

The stream of thought was stimulated by the rather tenuous analogy between base three counting (as suggested by Lemain) and the genetic code used by life on earth. Each coding unit (the jargon is "codon") consists of a group of three "bases". There are a total of four bases to choose from, which allows for 64 different codons (4 x 4 x 4), provided that the reading direction is determined (which it is). There is a lot of redundancy in the system, because these 64 codons only have to code for around 20 building blocks (amino acids). But we're drifting away from sailing. Sorry. And before the molecular biologists shoot me down in flames, please allow me to point out that this is the stuff I learnt 40 years ago, so it's likely to be a bit rusty.

Mark

 

[sarabande]

That's a much better explanation than I have ever come across ! Thanks

 

[Danny Jo]

[ QUOTE ]
I don't understand why you need to mark your cable every 5 metres, every 10 metres [or 5 fathoms for Imperialists] seems quite adequate to me and this would halve the work of marking it.

[/ QUOTE ] Yes, 9 marks instead of 18.
10 = Y
20 = B
30 = BY
40 = BB
50 = BBY

Tempting. But I'm used to working with marks every 5 metres, and reckon that a little bit of redundancy is a good thing.

Mark

 

[davies]

The colour-blindness issue matters when there is light, but at night all cats (and cable markers) are grey even to those with normal colour vision, which is why I prefer a cable-tie system (long = 10m, short = 5m) even though occasional checking and replacement is needed.
Isn't there a lateral thinking way round this? Most prudent sailors fake out the cable that they will need on the side-deck before launching to ensure that there is no risk of a snarl-up below the navel pipe at the moment of truth. It isn't hard to use a point 5m aft so that it just becomes a matter of pulling up the appropriate number of doubled 5m lengths, which can be counted even on the dirtiest night. I religiously maintain my cable-tie markers, but I can't recall the last time when I actually used them.

 

[Danny Jo]

[ QUOTE ]
The colour-blindness issue matters when there is light, but at night all cats (and cable markers) are grey even to those with normal colour vision

[/ QUOTE ] Yes, quite. That is why I have attempted to choose three markers with different grey scale values: black is very dark grey against the grey chain; yellow, or at least white is a lighter grey than the chain.

Good point, though - prompts me to consider testing proposed colours by moonlight.

Mark

 

[LadyInBed]

A simple incremental number of markers (tie wraps or stitched on cord tails) works well for day or night.
The cord tails don't do any damage if they slip through your hand.

 

[Poignard]

I read about a system used by the Pardeys [I think] to mark a 60 metre cable which makes sense to me. They use short lengths of sailmakers' tape stitched securely around the links as follows:-

10 m from the anchor - 1 tab
20 m - 2 tabs
30 m - 3 tabs
40 m - 2 tabs, with a black line across the tabs [made with a marker pen]
50 m - 1 tab, also with a black line across the tab

The benefits of this system are that the soft tabs don't cut your hands, don't snag in the windlass gypsy and the cable can be end-for-ended to equalise wear without needing re-marking.

You could, of course, use a similar system for marking at 5 metre intervals if that's what you prefer.

 

[onenyala]

I have used a loop of blue polypropylene twine, cow hitched to the appropriate point on the chain and then knotted 1 knot for 5m, 2 knots for 10 metres etc. Easily visible and easily felt in the dark.

 

[webcraft]

You are all of course quite mad . . .

a) Marking a chain every 10m is more than sufficient - whyon earth do you need a mark every five metres? Especially once you are over 20m?
b) Ribbon doesn't hurt your hands, runs through the windlass OK and comes in different colours - are we the only people using it?
c) Our ribbon at 11m, 21m and 31m has stayed on for at least four years
d) If its dark wear a head torch to see the colours

- Nick

 

[Danny Jo]

[ QUOTE ]
You are all of course quite mad . .

[/ QUOTE ]
Mad as a hatter, but not especially proud of it.

I like the coloured ribbons idea. Especially as it's not incompatible with knotted cord. I could have both, and save the expense of a head torch.

 

[kengill]

Why do you presume that the person anchoring is able to see?

You have not made any provision for braille marking.

There again you could just count the number of seconds of run out and convert that to metres , fathoms, rods, poles or perches against previous calibration runs. The marks will never wear out and it can be done in the dark

Or by a visually impaired person.

 

[silver-fox]

Why not just seetle for white as a marker every 10 metres as follows

10 metre = 1 white link
20 metre = 2 white links
30 mete = 3 white links....and so on

If you are worried about spotting such a small marker on a dark night then then paint a border colour either side (in say yellow)for a few links to highlight the white links.

Obviously past 100 metres of chain the slower mathematicians will need to anchor in open toe sandals or barefeet...../forums/images/graemlins/grin.gif