DIY Jackstays - D ring strength
- Thread starter stranded
- Start date
LadyInBed
Well-known member
To me, these look mechanically stronger than a wide D shackle.
I use the oval version of the IKV01, I didn't know there was a triangular version. The screw joint on a straight rod just seems to me to be stronger (edit - 31kN max load) than the joint on a D shackle, I'm sure others will confirm or tell me I'm wrong ?
And from above, I have now been told that you can get dyneema tape! Is it spliceable?
I don't know why people whinge about this forum, so much useful info disseminated - ok, sometimes it's wrong ?
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stranded
Well-known member
That is really useful - and very reassuring too - just need to put in the inches really.
thinwater
Well-known member
The OP really needs to state the size of his boat (length of jackstay). Like building a bridge, the correct material depends on the length, even though World Sailing standards do not state this for jackstays (but they do for lifelines--weird).
Ronstan wide D shackles will get you the width in a smaller size.
Dyneema does NOT stretch, so if it is straight the tight rope force when it takes a fit will be several times higher than polyester. To take a hard fall in longer lengths requires that you go up a size in both line and fittings.
Jackstay (jackline) Testing
Yes, I've taken some falls against tethers and jackstays, mostly when testing sea anchors and drogues in gale conditions (two hands for the testing!). I used polyester rope because it holds up better; I routed them so they were not under foot (along the cabin). Several take aways:
tether unlocking
Ronstan wide D shackles will get you the width in a smaller size.
Dyneema does NOT stretch, so if it is straight the tight rope force when it takes a fit will be several times higher than polyester. To take a hard fall in longer lengths requires that you go up a size in both line and fittings.
Jackstay (jackline) Testing
Yes, I've taken some falls against tethers and jackstays, mostly when testing sea anchors and drogues in gale conditions (two hands for the testing!). I used polyester rope because it holds up better; I routed them so they were not under foot (along the cabin). Several take aways:
- If you are clipped direct to a hard point it is jarring. You need to try this with a tether hooked to a tree to understand it. Tethers have snapped in hard falls and clips have broken. But ONLY when clipped to a hard point. I switched to nylon tethers for better shock absorption.
- Longer boats need stronger, lower stretch jacklines. Kinna obvious? 1/4" Dyneema is a good choice.
- Get good clips. I like the Kong Tango and Wichard Proline. Others may be weak when cross loaded or open if twisted.
tether unlocking
stranded
Well-known member
Some interesting stuff there. Be interesting to know how many people are estimated to have died/suffered serious injury as a result of following the lower standard that would have been avoided by following the suggested gold standard. Our jackstays will be 9.5m so I’m comfortable with the slightly beefier version of Jimmy Green’s 1” polyester webbing while we are stuck with coastal/<=24hr passages. Will revisit looking at those numbers when we refit for serious offshore.
dukeofted
Member
The best screwed connectors are made by Maillon Rapide 3mm Maillon Rapide Delta, Stainless Steel Quick Link
Sandy
Well-known member
Why not pop along to Jimmy Green's and get them to sort you out. While they are making up the stuff pop down to the Dolphin and have a pint and some delicious crab sandwiches.
stranded
Well-known member
Everything about that is right except that is what I have done throughout my ownership of Nooka - can’t Fford that now - time for me to grasp the nettle and sort things out myself - which as you know from helping me with the charging issue is a fine way to discover how little I know and how much I have to learn. Might drive down for the pint and crab sandwiches anyway though!