Snatch loads - Rule of thumb.

Snowgoose-1

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I am required to wear one on one of the vessels I sail. The elastic keeps the tether out of the way when walking about the deck and does not interfere when needing the length when working on the bowsprit.

On my own boat I prefer non elasticated.
Thanks for the very helpful replies.

I plan to do away with side deck jackstays. I will be fitting stainless clip on points midships using a 3 hook tether. I think I can make it work on a 26' boat. Apart from close to the bow , tether length would save me going overboard. There is a fairly recent case where a yachtsman went overboard attached but sadly still drowned.

Although some science can be applied to fittings , seems bigger is better. The only
experience I have of snatch loads was I suppose ,whiplash where we struck a moored OD at about 3 knots . The mast snapped almost immediately. Fortunately the owner took it very well and said he probably needed a new mast anyway.
 
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Pye_End

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3 point tether, one elasticated. 26 footer. Jackstays permanant and metal, so always there, and as far near the centreline as the boat design allows. 10mm (I think) U bolts at either end. Tethers rigged over the sprayhood to jackstays so can clip on easier when starting to go forward. On really big trips also put a line from the bow back to the (keel stepped) mast to give an extra attatchnent (though not ideal). Netting round guardrail forward of the mast to reduce risk of going through the gap. My preference for when it all gets a bit lively. Best off never put it to the test though.
 

Stemar

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The best jackstay design I've seen, apart from some really clever - and, no doubt, expensive - stuff on Pilot boats, is fitted to Catalacs. It's basically a long bronze handrail fitted to the coachroof in which a slide with an eye is free to move from one end to the other - no UV degradation, and nothing underfoot.

But, as mentioned, the best thing is use it, but not test it
 

srm

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At what age do you get cold feet and replace them - a year, five years, six months?
I follow the advice given by a surveyor who (unlike another I had the misfortune to employ) knew what he was talking about.
"replace webbing when you notice the colour is starting to fade".
Since then my jackstays are kept below when not likely to be used so a time based count is not relevant.
 

LittleSister

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I am required to wear one on one of the vessels I sail. The elastic keeps the tether out of the way when walking about the deck and does not interfere when needing the length when working on the bowsprit.

On my own boat I prefer non elasticated.

I'm guessing you mean on the harness you're wearing, an elasticised sleeve on the webbing or rope, intended to keep the tether tidy and from under your feet.

If so, the elastic in it is so weak it will have negligible effect if you are being thrown over the side - the elastic has to stretch easily so you can use the full length of the non-elastic tether.

Handy for its intended purpose (and I can't see any reason apart from cost not to prefer them with this), but useless at reducing the load on the jackstays in the event of a tumble - you will instantaneously be at full extent of the elastic with all your weight and the inertia of your fall on the webbing/rope/wire.
 

zoidberg

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My sailing now is mainly two-handed and single-handed. I have 6 or 7 tethers in good nick and, when in the cockpit on my own, I use two of them - and am quite happy 'doubling' one around a jackstay to shorten its effective length. Same thing if I need to work on the foredeck at sea. By and large, I'm with Pye_End on this.

Whatever you plump for, and as long as it works for you, that's fine. If it doesn't work for you when you need it to, it's one hell of an expensive lesson..... ad you're unlikely to come back here and tell us so.
 
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