Does anyone know how much a whoopie hook de-rates the load carrying capacity of 7/64 amsteel?
Does anyone know how much a whoopie hook de-rates the load carrying capacity of 7/64 amsteel?
I know that there is a long thread on a similar topic but it doesn't cover something like a whoopie hook unless I overlooked it. I like the idea of the hooks and would like to buy a couple but I would like to be able to figure the factor of safety on my suspension. I'm comfortable with something around 3 which is pretty standard for rigging and ropes.
Don't know the actually number but there are lots of whoopie hook users around so you have nothing to worry about. Dutch wouldn't sell something without an acceptable safety margin.
Don't let life get in the way of living.
Actually that thread did cover it...sort of.
In testing, amsteel is pulled to failure by fixed eyes looped around pins of a diameter twice that of the amsteel, so...a pin diameter (D) divided by the rope diameter (d) equaling 2 will provide full single line strength. This is expressed as D/d=2.
Samson Rope's (amsteel's manufacturer) literature states that a D/d of 1, "did not show significant strength loss, however break occurred at the back of the eye" which usually occurs at the base of the eye splice.
Short version...a whoopie hook is the same (or slightly thicker) thickness as 7/64" amsteel providing a D/d of 1 that theoretically does not derate the strength.
With that said, it is my suspicion that because the edges of a whoopie hoop are slightly chamfered, but not fully radiused, that there might be a slight loss of strength. Judging by the success of whoopie hooks, one would conclude that sufficient strength remains.
It's not repetitive stress on the same section of rope, if you are using whoopie hooks on the adjustable loop of the whoopie. The whoopie hook will likely never be in the same position on the rope.
Now if the whoopie hook were spliced on the fixed loop, or on the continuous loop attached to the hammock, I could see a concern.
I have been testing the limits of safe splicing with whoopie hooks for a while now...
ImageUploadedByTapatalk1380089739.743749.jpg
I've seen wear on my continuous loop in the channel end, enough that I'm watching it. But it seems to be holding strong.
Zach Rohe Photography https://zachrohe.com
I think your hammock will rip long before the amsteel will fail.
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