Over stretched guard wire.

You can't "repair them" as such. The end fittings are swaged on to the wire and can't be moved. The wires don't "stretch" very much anyway, so if they are close to the end of their adjustment they'll either fit or not. Do they fit now?
 
Can you connect them to the boat at one end with a short lashing? I've seen some where the guard rail wires don't go all the way from pulpit to pushpit, but stop an inch or two short at one end and are then connected to the (say) pushpit with a short rope lashing so that it can be cut with a knife in an emergency.
 
If they appear to have gradually stretched over the years, they almost certainly haven't. What has happened is that, by tightening them every so often, the stanchions have gradually been bent inwards and shortened the distance from pushpit to pulpit.
 
As said the wires won't stretch. My guess is that on or ,ore of the stanchions has been bent inward to allow wire to seem longer.
If you do decide to have the wires shortened you will need to have a new roll swaged fitting on one end. As said also lashing of cord is good because it can be cut or fit a pelican hook for easy disconnect/ reconnect.
You might need to disconnect in a hurry in MOB situation 0or just boarding from a dinghy. good luck olewill
 
As that looks like dodgy plastic covered wire, bin the lot and start again with bare stainless wire, and throw in one of my pet hobby horses, decent pelican hooks at the pushpit end, while you're at it ! :)
 
Sneaky Pete said:
The guard rails similar to the one in the photo are almost on their limit of stretch very little adjustment left in them. How can these be repaired or who would repair them looks like the sleeves are crimped over the wire itself.

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If I understand you correctly the wire has stretched too long........

Extend the threads on the end with the nut, there seems to be at least an extra couple of inches. You can buy a single 'die' of the correct pitch from any motor factors, then shorten the end with a hacksaw to suit.
 
Like others have mentioned before the staunchions have possibly bent in
Turn the staunchions round in the socket if possible so that they are bent out
If this does not work check the bases they may have distorted or come loose so you need to attend to them

Alternatively take the wires to a rigger, get the end fitting cut off & a new one fitted
This will mean wires are now about 6 inches too short
Couple them with rope lashings & you will have a safer unit
Remember to end for end them & the staunchion will not rub in the same place
I had a new one made for a 31 ft boat & it cost £40-00
 
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Plastic covered is bad news, hides any corrosion so if you rebuild then do it with plain wire.

Stainless wire stretching ... nope the stanchions have bent in, lots of alternatives discussed above.

Hint for the future.....stop people from using the lifelines to climb aboard!
 
nimbusgb said:
Hint for the future.....stop people from using the lifelines to climb aboard!
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Good point, why do visitors to ones boat insist on yanking the wires as hard as they can.
When berthing i m often single handed so appreciate help but really squirm when people insist on tugging at the guardrail wires
My family are drilled to get aboard by the shrouds where they can reach higher up & to pull on cleated ropes, or staunchion bases , not staunchion tops
 
nimbusgb said:
..... stop people from using the lifelines to climb aboard!
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Daydream believer said:
... why do visitors to ones boat insist on yanking the wires as hard as they can. .....
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Guardrails and their stanchions should take the weight of an adult and withstand this type of use. If they cant they are too weak for the job and most likely the stanchion base needs beefed up or the mount made good again.
 
Sorry to rain on the parade BUT safety DOES stretch. It might only be a tad BUT it does stretch. I agree with the point that the stanchions COULD have bent. However usualy the ends of safety wires are fixed to the Pushpit and Pulpit and not to a stanchion-hence the OP saying there has been some stretch.

Peter
 
steel wire rope can experience elastic and plastic deformation.


Elastic Stretch = (W x L) / (E x A)

W = Applied Load ( kN )
L = Cable length ( mm )
E = Strand Modulus ( kN/mm²)
A = Area of Cable = (D2 x pi) / 4 (where D= Dia of cable mm)



That is for a straight line pull, and as has been pointed out, a guard rail wire is frequently set in a curve, which makes plastic deformation of the stanchion(s) or local movement of the support base quite easy over time. The radius of curvature is then altered, making the wire slack. That same radius 'magnifies' any tension in the wire when it is tightened, which aggravates the problem.


Plastic (permanent) deformation is most likely to occur when the rope is bent (e.g. round a thimble), or impacted by e.g. a spinnaker pole near a stanchion.

For both processes, quite large forces are required.
 
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Could cut the ends off yourself and fit stalok swageless eye type end fittings yourself , may need link shackles for lashings circa £20 each or cheaper on you know where,and they are
reuseable. I think pvc covered wire is good until the covering wears through and allows water penetration ,crevice corrosion and all that so regular renewal is probably sensible.
 
sarabande said:
steel wire rope can experience elastic and plastic deformation.


Elastic Stretch = (W x L) / (E x A)

W = Applied Load ( kN )
L = Cable length ( mm )
E = Strand Modulus ( kN/mm²)
A = Area of Cable = (D2 x pi) / 4 (where D= Dia of cable mm)



That is for a straight line pull, and as has been pointed out, a guard rail wire is frequently set in a curve, which makes plastic deformation of the stanchion(s) or local movement of the support base quite easy over time. The radius of curvature is then altered, making the wire slack. That same radius 'magnifies' any tension in the wire when it is tightened, which aggravates the problem.


Plastic (permanent) deformation is most likely to occur when the rope is bent (e.g. round a thimble), or impacted by e.g. a spinnaker pole near a stanchion.

For both processes, quite large forces are required.
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Very well put. The reason that there are BOTTLE SCREWS at the end of safety wires is to adjust them after some time due to the STRETCH!

Peter
 
I'm not at all convinced about wire stretch, I'd think any slack is down to stanchion flexing, and doesn't require bent stanchions; though turning bent stanchions facing outwards seems a tad unfriendly and possibly a source of snagging on other boats, walls etc.

Bottlescrews or lashings are to take up tension when the wire is fitted, it has to be tensioned somehow...

Plastic covered wire is the invention of the devil, and there's a reason it is not allowed on offshore racing boats; I have seen it fail on several lightly used boats.
 
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Seajet said:
I'm not at all convinced about wire stretch, I'd think any slack is down to stanchion flexing, and doesn't require bent stanchions; though turning bent stanchions facing outwards seems a tad unfriendly and possibly a source of snagging on other boats, walls etc.

Bottlescrews or lashings are to take up tension when the wire is fitted, it has to be tensioned somehow...

Plastic covered wire is the invention of the devil, and there's a reason it is not allowed on offshore racing boats; I have seen it fail on several lightly used boats.
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+1.
If the wire has stretched permanently it's gone into plastic deformation from severe overloading and you should really be thinking about binning it.
From memory elastic elongation is something like 0.0001 for 1% of breaking load of wire, so 1m will stretch by 0.5mm under 5% of breaking load of the wire. Again from memory, 3mm capacity is about 8Kn so stretch a metre by 1mm and the load should be about 0.48Kn or 80 Kg.
Probably. Possibly. Something like that, slightly different or dyform & rod. :)
 
Hitting things with the pulpit or having the pushpit run into causes the same effect of loose wires. The plastic sheathing is easy to remove - just run a Stanley knife along it and peel it off. One of the reasons for tying the guard wires with cord was to avoid a continuous conductive ring round the boat when using RDF - not usually a problem these days.
 
I have stainless pelican hooks at the pushpit ends, and shackles direct to the pulpit eyes; with a big enough box of odd shackles for trial and error there's no need to resort to lashings or bottlescrews.

As awol says, lashings were mainly used to avoid quadrantal error with RDF; nowadays there's no excuse, the MOB thing is madness if one thinks about it; cut the lashings to recover a MOB, and you're left without guardrails on at least one side, quite possibly in serious conditions but never a good thing.

Pelican hooks are useful every time one gets in and out of a dinghy, and when alongside a pontoon one can make the cockpit more accessible by clipping the guardrails forward to the next stanchion, keeping the wires tensioned for fenders.
 
Seajet said:
As that looks like dodgy plastic covered wire, bin the lot and start again with bare stainless wire, and throw in one of my pet hobby horses, decent pelican hooks at the pushpit end, while you're at it ! :)
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Been there on this one, changing the end to an eye for lashing does not help, as the eye still leaves the wire too long. For not many quids local rigger cut off the end and swaged new fitting, at the same time showing reassuringly that the wire despite appearance of surface rust at the entrance to the swage was in very good condition. Also put down the old wives tale above.
 
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