Holding a 10lbs weight with your arm straight down is a lot easier than hold the same 10 lbs with your arm extended out parallel to the ground.
Holding a 10lbs weight with your arm straight down is a lot easier than hold the same 10 lbs with your arm extended out parallel to the ground.
Don't let life get in the way of living.
Aye...captain, but when Spock stretches out his arm to bear that weight with me my deltoids work less!Originally Posted by Bubba
Makes sense. Vulcans are after all 3 times stronger than humans.Aye...captain, but when Spock stretches out his arm to bear that weight with me my deltoids work less!
Don't let life get in the way of living.
Well....I had to see for myself.Sorry for the lousy quality pics.
I'm convinced.............how about you?
When I simulated a SLS with my fish scale inline the tension on the line measured 2# 4oz., I hung a cord the same length as my hammock connected that to 2 marlin spikes to simulate descending rings and then hung 2 - 5# dumbells across the center and the scale read 20# 6oz. So the weight on a taunt line nearly doubles.
Interestingly when I simulated the tree strap to whoopie via marlin spike with no ridgeline the 10#'s of dumbells only registered 9#'s 9 oz. the addition of a ridgeline that was 83% the length of the hammock length of rope caused a 10# 7 oz load.
If yuin was a wonderin' my wife's lil' dumbells really do weigh 10#'s!
So without a derating factor for knots (don't know that rule) and adding another 50% a 200# guy should be OK with a single length of rope rated @ 600#'s. Given that a single run of dynaglide rated @ 1000#'s seems to nearly double the 200# guys need with the 50% safety factor.
Is that correct? A couple of tree straps, a couple of descending rings, and a length of dynaglide? That sounds like something a weight weenie would approve of.
What say you?
Last edited by dirtwheels; 06-18-2012 at 20:18.
To the O.P.: since this is simple trigonometry, there are two ways to learn this principle. You can either take a class in trig and be convinced through axiums and postulates, or hang from zing-it and let your bruised butt convince you. I would recommend the former
Mike
"Life is a Project!"
Scotty could help too!
It's been some time since I took trig, but I did OK, I have been hanging (low to the ground mind you) from 400# cord for over a week now. Thanks for your edumacated advice.To the O.P.: since this is simple trigonometry, there are two ways to learn this principle. You can either take a class in trig and be convinced through axiums and postulates, or hang from zing-it and let your bruised butt convince you. I would recommend the former
Several hangers hang on dynaglide. It just doesn't leave much of a safety factor. Many of us want a safety factor of 5x.
I'm guessing you don't have the correct link (or something) for the photos. When I try to open them in another window, the host site asks me to sign in.
I haven't signed up for a photo sharing service. Is there a derating factor by knot or a rule of thumb to use in general?
The pic links you posted earlier were obviously from a MS Live email account rather than a photo host. Those links are only visiible by you when you're logged in to that account. You'll either need to upload them to a photohost directly, or upload to the forum gallery if they are hammock related and still want to link them.
The rule of thumb is that you should consider cording de-rated by at least 50% if there's a knot. It isn't specific to a particular knot, although some de-rate more than others.
“I think that when the lies are all told and forgot the truth will be there yet. It dont move about from place to place and it dont change from time to time. You cant corrupt it any more than you can salt salt.” - Cormac McCarthy
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