How tight shall I do my new guard rail wires?

xyachtdave

xyachtdave

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Admission first - I'm a bit of a tart for aesthetics!

I have just fitted my new guard wires and done them up hand tight so it's all straight and not baggy. A massive improvement over the old stuff and with the newly straightened stanchions looks great.

The next person spotted pushing the boat around by the stanchions is in trouble...

I'm now back at home wondering if a bit of slack is desirable, even if it looks like the lines were poorly measured?

Thoughts appreciated!
 
if they are slack, you can't lean against them at sea to get a purchase of tails or when moving sailbags.
 
So that if plucked they resonate at the f below c three octaves below middle C.




Which coincidentally the lowest note on a grand piano ........









Thats why riggers always have a grand piano in their tool bag. :)
 
" f below c three octaves below middle C."


My transistorised Steinway only goes down to A below the lowest C. So about 27Hz.


Which makes it almost inaudible to humans, but the same resonant frequency as the stomach and entrails. So plucking the guardwires will make you sick....Boom ! Boom !
 
xyachtdave said:
Admission first - I'm a bit of a tart for aesthetics!

I have just fitted my new guard wires and done them up hand tight so it's all straight and not baggy. A massive improvement over the old stuff and with the newly straightened stanchions looks great.

The next person spotted pushing the boat around by the stanchions is in trouble...

I'm now back at home wondering if a bit of slack is desirable, even if it looks like the lines were poorly measured?

Thoughts appreciated!
Click to expand...

When I fitted mine last spring, I took up the slack and half a turn on the rigging screw just to put a little tension on without being banjo tight.
If they are really tight when you fall against them or deflect them too much, they could bend the stanchions and then you are back to slack wires again anyway.
 
If you're going to race and you expect your crew to hike properly (and really serious crew would expect to have to hike properly) then you'll need them to be a bit slacker.
 
ISAF Offshore Special Regulations

3.14.2
a)
When a deflecting force of 40N is applied to a life line midway between supports of an upper or single lifeline, the lifeline shall not deflect more than 50mm. This measurement shall be taken at the widest span between supports that are aft of the mast.

The main purpose of LIFElines lies in their name, otherwise they would be called decorations. ;)
 
But
"When a deflecting force of 40N is applied to a life line midway between supports of an upper or single lifeline,"
is surely complete bullexs, because when a shock load, like a crew member falling against the life line in bad sea conditions, the number of N is greater than 40N
?
 
Straight but not so tight that they course problems with the slightly 'less tight' gate wires. As you want to be able to unclip with ease. Dont expect at any time to be anpble to do so with fenders dangling over the side.
 
Boreades said:
But
"When a deflecting force of 40N is applied to a life line midway between supports of an upper or single lifeline,"
is surely complete bullexs, because when a shock load, like a crew member falling against the life line in bad sea conditions, the number of N is greater than 40N
?
Click to expand...

:confused:

So they will then deflect more than 50mm. So where's the problem?
 
PuffTheMagicDragon said:
ISAF Offshore Special Regulations

3.14.2
a)
When a deflecting force of 40N is applied to a life line midway between supports of an upper or single lifeline, the lifeline shall not deflect more than 50mm. This measurement shall be taken at the widest span between supports that are aft of the mast.
Click to expand...

That's to stop them being slackened so much for crew to hike that they cease to be effective enough as guard wires. It's not a spec for guardwire tightness on a cruiser.
 
Long ago I gave up on using wire for guard rails and substituted dyneema. No more fractured ribs when you fall against them and a considerably greater SWL than plastic covered guard rail of the same diameter o/a. In fact it's easy to achieve the ISAF/OSR deflections (I hope those sticklers for the regulations are NOT using plastic-covered wire).
There are several other side benefits - no longer do incompetents try and fend off using the guard-strings and ignorant visitors coming aboard don't try and use them for purchase when pulling on ropes.
In answer to the OP, have them tight, though it won't last if you insist on hanging your fenders on them.
 
I used to hang my fenders on the old guard wires, not anymore....'Tie the fenders to the stanchion bases please,'.....'Yes they're the straight shiny things you're not allowed to push on,'.........'Yes that's it, with the barbed wire between them,'. :)

Thanks for the ISAF regs above, probably a good benchmark even for us humble cruisers, I'm sure there was an 8 hour long committee meeting discussing the pros and cons of the tightness to get that in the rules.
 
PuffTheMagicDragon said:
The main purpose of LIFElines lies in their name, otherwise they would be called decorations. ;)
Click to expand...

It may be different on racing boats where the crew like to sit legs a-dangle over the edge, but on a cruising boat I think the best term would be "tripwires" (or "TRIPwires, if you prefer). I have 'em, but I don't think they contribute to my safety, though they are useful for tying the fenders on.
 
" I'm sure there was an 8 hour long committee meeting discussing the pros and cons of the tightness to get that in the rules."
Someone's got to decide these things!
 
Boreades said:
But
"When a deflecting force of 40N is applied to a life line midway between supports of an upper or single lifeline,"
is surely complete bullexs, because when a shock load, like a crew member falling against the life line in bad sea conditions, the number of N is greater than 40N
?
Click to expand...
That is just a measure of tension and could be scaled as appropriate

In my opinion the most important function of lifelines is to act as a handrail - to support you when you place a hand on it or stagger against it. For that to be effective you need limited deflection when you put a moderate weight on it. I did once have a line that was too slack and that felt unsafe going forwards - even when on a mooring

I don't think you can rely on lifelines to hold you on board if you fling your entire body weight against them - too easy to go over, under. through and so on.
 
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