Look at the link outdoorsguy posted, it has some more info. Basically the weak point is the exit of the adjustable bury. For most diameters of lines it is only reduced to 80%. I'm wondering if the 60% is for the 8-strand 7/64 and the 80% for everything else since it's then 12-strand. That part is just speculation on my part.
Exactly, you're not even close to the 960lb break point the whoopie takes the rope down to. It's safe, you're just taking your safety factor down to almost 2. If that is something you're comfortable with, enjoy yourself.
Just to add a perspective I'll explain safe working loads (SWL) for anyone who isn't already familiar. In conversations I've had with others on the forum it seems that 3 is a common safety factor for hammocking applications. So, you take your break strength of the rope and divide by your safety factor which yields the SWL. So, 960/3= 320. To put this in perspective it seems that a rule of thumb safety factor for lifting objects is 5-7 and it goes up to 10-15, depending on the source, if people are on the line.
I think the main reason that hammockers are content with a safety factor of 3 is that generally we're only falling a foot if something breaks.
This is where I got my info:
http://www.animatedknots.com/reliability.php
http://kickinteractive.com/dc/units/1_1/safety.html
http://whitewatersolutions.net/Rope_..._Strength.html
Everyone has to hang their own hammock. I just want to make sure that if someone is taking a risk, like using Dynaglide for whoopies, they know what the risks are.
WOW! After lurking here for a while, this just proves to me how much I love this forum!
The amount of info is amazing
7/64ths should be OK it sounds like. I just wont hang over a drop off that i am not willing to fall in the middle of the night to be safe.
Thanks again!
Here's the pertinent info from the referenced thread Knotty posted. This is a quote from the email he received from Samson.
Recently the reduction to 60% of average break strength for Amsteel Blue whoopie slings was suspected to be a low value. Testing showed that it is actually around 80% depending on the size of the rope. On every test done the break location was at the point of the adjustable whoopie tail exit.
In collusion, the locking brummel has less impact on break strength reduction than the "sudden transition in size where the adjustable section exits the bury". If a traditional buried eye replaced the brummel, the same strength reduction would be expected because the adjustable bury exit is the weakest link.
Best regards,
Mark Pederson
R&D Engineer
It may be that everyone is correct here, given that the rope size was not expressed explicitly for the given deratings. Ever since I've been hanging I've used the above info for myself and shared it with others, as I counted it to be trustworthy, but I never noticed the "depending" part before as I highlighted. The best scenario would be to have Samson test a whoopie sling that we use for hanging. Then there would be actual numbers for our user group.
Go with what you are comfortable with. It's really important to inspect your gear, especially the load bearing stuff, checking for wear and replacing as needed. My original set of whoopies is 3 yrs in use now, showing some frazz, and I keep on using it to see how far it will go. This is my choice for me, as I deem falling a foot to be an acceptable risk for myself in the grand experiment. There will probably be a day that I retire them before failure, but not yet. HYOH.
made a set of WHOOPIES for myself, this week
had a 40" piece of it left over & decided to play with it
made a double ended connector w/ 2" loops on each end
did the double lock trick w/ a 6" bury on each(sorry if i used the wrong terms)
the end result is a 20" piece
i took the connector & w/ one end looped thru a short piece of chain & the other end looped around the ball on my Jeep hitch, i hooked onto my grandson's 1-ton diesel dually
i was able to tow the truck 100'+, across the pasture & he towed me the 100' back
though we didn't do any braking or jerking, i still thought it was a pretty good test
the boy was impressed...
sw
"we are the people our parents warned us about" jb
steve
Years ago I called Samson Rope to try and get the test criteria for their 60% rating. They could/would not provide me with actual test data. As I told another forum member, Samson Rope is a large corporation whose products are used on far heavier loads costing much more than what we do. I believe they are very conservative with their ratings as they should be in today's legal environment. I told Samson what I do with their 7/64" Amsteel Blue line and they stated that the sling should rating 90-100% of the line strength. We tested many slings with a 1600 pound static load and all held just fine. Some were even tested with additional weight without failure.
Remember that whoopie slings originated in the arborist/timber industry where the dynamic loads of a large log being hoisted out of a forest are much different than what we do. I wonder if Samson make have taken that into account on their rating?
The use of 7/64" Amsteel Blue for hammock suspension has not been an issue when properly constructed. Good advice from Detail Man as to always inspect your gear and replace at sings of excessive wear or damage.
Last edited by SmokeBait; 04-17-2013 at 09:22. Reason: typo
I'm a big guy. My wife is a little women. Together we are well ove 400 pounds in my hammock. It is hung with 7/64 Amsteel Blue. You should have no problems at all bro. God BLess
I can attest to over 400 lbs in my hammock... Me, my wife, and our dog. The dog was moving around quite a bit too. I have no concerns with 7/64 Amsteel, though I would be reluctant to go to Dynaglide... Not necessarily because I don't trust it, but because the weight savings is not worth the potential for failure for me. Hang your own hang.
"We're the Sultans of Swing."
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