CJU
Well-Known Member
Does anyone know if 4mm 1/19 S/S would be strong enough for jackstays. I particularly want S/S, not webbing, and I have some spare 4mm that I can use.
Jackstays in S/S
- Thread starter CJU
- Start date
npf1
Well-Known Member
FWIW...
I seem to recall that the webbing used for jackstays normally has a breaking load of around 2000-3000kg.
I found a page on Google showing an example of 4mm 1/19 SS wire has a min breaking load of 1280kg
I seem to recall that the webbing used for jackstays normally has a breaking load of around 2000-3000kg.
I found a page on Google showing an example of 4mm 1/19 SS wire has a min breaking load of 1280kg
saltwater_gypsy
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I have 5mm SS in a Lifestay system. (continuous latching ststem)It is supported at each stanchion so the mechanics are different compared to a long span.
If you do some Googling you find that the breaking strain of 4mm 1x19 SS is about 1400kg and the breaking strain of 25mm webbing is about 1350kg.So not much to choose from.
I reckon that, with all safety systems , the strength of the attachment points etc is as important as the lifeline itself.
If you do some Googling you find that the breaking strain of 4mm 1x19 SS is about 1400kg and the breaking strain of 25mm webbing is about 1350kg.So not much to choose from.
I reckon that, with all safety systems , the strength of the attachment points etc is as important as the lifeline itself.
nimbusgb
Well-Known Member
Just in case you are not aware of it, the problem with s/s cable jackstays is that they roll underfoot.
CJU
Well-Known Member
Thanks all. We had S/S jackstays on our old yacht and didn't find it a problem and I'm a bit doubtful about webbing degrading after being exposed to sunlight.
lw395
Well-Known Member
RORC category 1
4.04 Jackstays, Clipping Points and Static Safety Lines
4.04.1 The following shall be provided:
a) Jackstays:-
shall be providedi
attached to through-bolted or welded deck plates or other
suitable and strong anchorage fitted on deck, port and starboard
of the yacht's centre line to provide secure attachments for
safety harness:-
ii comprising stainless steel 1 x 19 wire of minimum diameter 5
mm (3/16 in), or webbing of equivalent strength;
iii which, when made from stainless steel wire shall be uncoated
and used without any sleeving;
iv 20kN (2,040 kgf or 4,500 lbf) min breaking strain webbing is
same for cat 3 with liferaft.
So it would appear not.
The wire is not expensive.
I know a family yacht with a few people on board is less likely to have the jackstays tested to the limits that a fully crewed racer, but I don't think this is the place for compromise.
I agree about sun-bleached webbing btw, it also holds a lot of dirt on the deck. I suspect the ideal is to route wire where it won't be under foot...
4.04 Jackstays, Clipping Points and Static Safety Lines
4.04.1 The following shall be provided:
a) Jackstays:-
shall be providedi
attached to through-bolted or welded deck plates or other
suitable and strong anchorage fitted on deck, port and starboard
of the yacht's centre line to provide secure attachments for
safety harness:-
ii comprising stainless steel 1 x 19 wire of minimum diameter 5
mm (3/16 in), or webbing of equivalent strength;
iii which, when made from stainless steel wire shall be uncoated
and used without any sleeving;
iv 20kN (2,040 kgf or 4,500 lbf) min breaking strain webbing is
same for cat 3 with liferaft.
So it would appear not.
The wire is not expensive.
I know a family yacht with a few people on board is less likely to have the jackstays tested to the limits that a fully crewed racer, but I don't think this is the place for compromise.
I agree about sun-bleached webbing btw, it also holds a lot of dirt on the deck. I suspect the ideal is to route wire where it won't be under foot...
CJU
Well-Known Member
Thanks again. I not only had the wire but the terminals too. Still as you say best not compromise.
PuffTheMagicDragon
Well-Known Member
I believe that you have accidentally missed some significant wording. /forums/images/graemlins/wink.gif
ISAF Offshore Special Regulations 2008-2009
"4.04 Jackstays, Clipping Points and Static Safety Lines
4.04.1 The following shall be provided:
a) Jackstays:- MoMu0,1,2,3
shall be provided
i attached to through-bolted or welded deck plates
or other suitable and strong anchorage fitted on
deck, port and starboard of the yacht's centre line
to provide secure attachments for safety
harness:-
MoMu0,1,2,3
ii comprising stainless steel 1 x 19 wire of minimum
diameter 5 mm (3/16 in), or webbing of equivalent
strength;
MoMu0,1,2,3
iii which, when made from stainless steel wire shall
be uncoated and used without any sleeving;
MoMu0,1,2,3
iv 20kN (2,040 kgf or 4,500 lbf) min breaking strain
webbing is recommended;
MoMu0,1,2,3"
Please note sub-section iv, which I have put in bold characters.
<span style="color
range">Orange</span> polyester webbing is more visible, does not roll underfoot and <u>does not degrade with exposure to UV</u>. Trust me: our UV Index in summer (May till October) is MORE than 11, practically on a daily basis. In any case, jacklines are usually taken below after a race or a passage.
ISAF Offshore Special Regulations 2008-2009
"4.04 Jackstays, Clipping Points and Static Safety Lines
4.04.1 The following shall be provided:
a) Jackstays:- MoMu0,1,2,3
shall be provided
i attached to through-bolted or welded deck plates
or other suitable and strong anchorage fitted on
deck, port and starboard of the yacht's centre line
to provide secure attachments for safety
harness:-
MoMu0,1,2,3
ii comprising stainless steel 1 x 19 wire of minimum
diameter 5 mm (3/16 in), or webbing of equivalent
strength;
MoMu0,1,2,3
iii which, when made from stainless steel wire shall
be uncoated and used without any sleeving;
MoMu0,1,2,3
iv 20kN (2,040 kgf or 4,500 lbf) min breaking strain
webbing is recommended;
MoMu0,1,2,3"
Please note sub-section iv, which I have put in bold characters.
<span style="color
range">Orange</span> polyester webbing is more visible, does not roll underfoot and <u>does not degrade with exposure to UV</u>. Trust me: our UV Index in summer (May till October) is MORE than 11, practically on a daily basis. In any case, jacklines are usually taken below after a race or a passage.Keith 66
Well-Known Member
Our new old boat had wire jackstays running down the side decks. The first thing i did when we got her home was to take trhem of, they were lethal, like walking on ball bearings!
lw395
Well-Known Member
I'm not sure that RORC intends to recommend 20kN webbing over SS.
Polyester webbing DOES lose strength in sunlight, albeit slower than some other fibres.
The trouble with removing jackstays after every trip is that it gets tempting not to put them on for a little day sail, then suddenly one day you want them. Also they need to be properly secured and checked.
For some yachts, wire is better if you can arrange it not to be under foot. For others, webbing would be my choice, with the acceptance that it will be replaced at intervals.
Its also important to have a variety of other clipping on points.
Polyester webbing DOES lose strength in sunlight, albeit slower than some other fibres.
The trouble with removing jackstays after every trip is that it gets tempting not to put them on for a little day sail, then suddenly one day you want them. Also they need to be properly secured and checked.
For some yachts, wire is better if you can arrange it not to be under foot. For others, webbing would be my choice, with the acceptance that it will be replaced at intervals.
Its also important to have a variety of other clipping on points.
PuffTheMagicDragon
Well-Known Member
I do agree that practically anything deteriorates with exposure to sunlight - and that includes me! /forums/images/graemlins/wink.gif
Seriously, though, the recommendation is there on the ISAF Offshore Special Regulations. You can download the full text in pdf form from http://www.sailing.org/specialregulations.php, which is where I copied and pasted. All I can say is that in the only international offshore race in which I am involved with scrutineering, the annual Rolex Middle Sea Race, all the participating boats that I have inspected over the years, without exception, were equipped with heavy duty webbing. I agree that it is a bit of a hassle to rig / unrig the jackstays, but it does give you an occasion to inspect them regularly. Personally, I prefer to rig mine over the coachroof rather than along the side deck, in the belief that it is safer on my boat; however, I do not race.
The main thing is to be safe at all time, but more especially at night.
Seriously, though, the recommendation is there on the ISAF Offshore Special Regulations. You can download the full text in pdf form from http://www.sailing.org/specialregulations.php, which is where I copied and pasted. All I can say is that in the only international offshore race in which I am involved with scrutineering, the annual Rolex Middle Sea Race, all the participating boats that I have inspected over the years, without exception, were equipped with heavy duty webbing. I agree that it is a bit of a hassle to rig / unrig the jackstays, but it does give you an occasion to inspect them regularly. Personally, I prefer to rig mine over the coachroof rather than along the side deck, in the belief that it is safer on my boat; however, I do not race.
The main thing is to be safe at all time, but more especially at night.
Juggler7823
Well-Known Member
Two points on this discussion:
a) Its not the webbing that degrades quickest, its the stitching. The Brit Glyn Charles was lost overboard in the Sidney-Hobart several years ago because the stitching on the end loop gave way. Incidentally dark coloured webbing and stitching degrades much faster than white.
b) Your decks always have the genny sheets running along the tracks. Its just as easy for these to roll underfoot as SS jackstays
a) Its not the webbing that degrades quickest, its the stitching. The Brit Glyn Charles was lost overboard in the Sidney-Hobart several years ago because the stitching on the end loop gave way. Incidentally dark coloured webbing and stitching degrades much faster than white.
b) Your decks always have the genny sheets running along the tracks. Its just as easy for these to roll underfoot as SS jackstays
PuffTheMagicDragon
Well-Known Member
I agree about the stitching. Not so sure about the colour except that it should be contrasting. Removing the webbing after use gives the opportunity to check the state of the stitching. Personally I would like ISAF to require webbing jackstays to include 'safety flags' such as are now a requirement on tethers. Incidentally, how many sailors do actually check the stitching on their tethers?
I don't agree with your statement re the genoa sheets lying along the deck. Even so, being somewhat 'squashy', unlike stainless 1x19 wire, they pose a lesser rolling hazard. IMHO.
I don't agree with your statement re the genoa sheets lying along the deck. Even so, being somewhat 'squashy', unlike stainless 1x19 wire, they pose a lesser rolling hazard. IMHO.
