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Discussion Starter · #1 ·
Our club boat carries 3 shotlines: 10m, 20m and 30m long. Each one has a screw gate carabiner at one end and a small loop at the other. In this way we can make up lines of 10, 20, 30, 40, 50 and 60 metres.

Over time these have got a bit ropey :eek:mg: and they were nasty polypropylene, I thought it would be nice to replace them with fabric covered climbing ropes. We have a few climbers in the club and they have an abundance of old ropes in their sheds. So they are free.

Now, the old ropes had loops formed by splicing the end which, when done properly, is very strong and compact. Trouble is, you can't splice climbing ropes. I've tied a bowline in the end but it's a big ugly knot in a 12 mm rope. As this type of rope is used on yachts , how do they put a permanent loop in the end? It has to be fairly strong to pull the shot weight up and foolproof so that no-one will chuck it in when its not secure. Think this is beyond the capability of my trusty cable ties.
 

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The only neat way I have found of putting a loop in Kernmantel is to sow the outer sheath and then do a whipping over the top.
 

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You can splice kernmantle rope, but it's hard work.

I found a pictorial guide here

I have also seen eyes made by using whipping twine around and stitched through the two ropes.

Are there any disadvantages to using climbing rope underwater? I've only used it on sailing yaughts as hallyards and sheets for the sails. I know climbing rope tends to be stretchy (good for absorbing the shock of a fall).

Personally, I'd be inclined to make do with a nice bowline - in 12mm, the knot's only going to be 50mm wide.

Or you could use cable ties - they're suprisingly strong.
 

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Discussion Starter · #5 ·
OK. That's looking better. At least I now know it's called kernmantle so I have a chance at getting some google results.

The advantage of using this rope is that its free!

@ Prometheus. My LDS has an industrial sewing machine for doing harnesses, weight belts etc. Would this work? Haven't found a "how to sew kernmantle rope" website yet.....
 

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Take them to a decent chandlers, a lot of them will splice loops in kernmantle for a couple of quid. Doing it yourself with a fid is a right a pain.

I keep some old climbing ropes on my RIB in case they're needed. They soak up water and stay wet forever (unless they're posh dry treated ropes). In winter they'll freeze solid in the coil if left on the boat. Just a word of warning from having learnt the hard way :rolleyes: Watch if you cut them and don't seal the ends as they tend to spill their guts when wet, again something I learned the hard way (kernmantle guts aren't good round props :rolleyes:).
 

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I do it with a sailmakers palm a big needle and waxed thread, but I am a luddite and make any thing I can to save paying someone else to do it.:)
 

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If you have that many climbers just put a climbers figure of eight in the end.
It might take all of ten seconds.
 

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+1 for the figure of eight, thats what climbers use on climbing ropes.
Stay away from bowlines they don't hold too well on stretchy dynamic ropes.
 

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I have used climbing ropes for a long time on my RIB, both as anchor lines and shotlines. They are very easy to handle as they don't tangle very easily so easy to use.
A figure of eight works well but can be hard to get out once tension has been put on the line. I use a modified alderney rig to recover mine with a grapnel so there tends to be some tension till the boat pulls out the hooked in tine!
Bowlines work better and work very well in kernmantel lines, just tie a stopper knot after it (half hitch) and you could lift the Titanic if the rope was long enough without slippage.
I am not sure I would bother with a splice as you will need to shorten the line most times and untie the weight etc. I personally have never felt the need but I suppose there are always other ways of doing things........:D
I have found there are only really four knots that you need on a boat. A fishermans bend, clove hitch, bowline and a half turn. All the rest are useful but not essential, none are hard to learn.
 

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Discussion Starter · #15 ·
Hokay.

Having had a play, I find that a neat figure of eight with the spare end whipped back onto the main bit is sufficiently compact and foolproof. Point is I don't want anyone to be untying the ends to adapt the lines, but use them as is. Joys of club diving.

Thanks for advice.
 

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Point is I don't want anyone to be untying the ends to adapt the lines, but use them as is. Joys of club diving.
As an old fishing boat skipper from Gigha told me years ago, never untie anything you can't re-tie :D

Use an overhand knot and give it a bit of load, especially on damp climbing rope. No-one will be untying that again.
 

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All of my shot lines are made up from 40 - 60 mtr lengths of climbing rope, I just tie a overhand knot on the bight to form an eye.

A trick i learned from my brother is to store them chain shortened, this stops them becoming tangled, and when i am deploying a shot i allow the shot to take what it needs from the chain and then use a double ended thumb bolt to keep it the length i need, as the thumb bolt will stop it unravelling, when its looped through the chain.

The reason i use climbing rope is that climbing shops always have lenghts that are too short for climbers and get sold off cheap.
 

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A trick i learned from my brother is to store them chain shortened, this stops them becoming tangled, and when i am deploying a shot i allow the shot to take what it needs from the chain and then use a double ended thumb bolt to keep it the length i need, as the thumb bolt will stop it unravelling, when its looped through the chain.
Can I show my ignorance here by asking what you mean by chain shortened?
 

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+1 on chaining the rope to store thats what we use on rope access jobs, then just drop em in the rope bag. It tangle proof and look right clever.
 
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