One site said that the whoopie would decrease rope strength by 12%. Still better than a knot, but not as good as a straight bury eye splice. (The straight bury is different from a locked Brummel)
Last edited by SlowBro; 07-06-2009 at 20:07.
For the fixed eye splices, "lock" the bury by sewing the tail end of the bury. Samson Ropes has a pdf on their site. Page down to the end of the pdf file for the directions on "sewing" the tail end of the bury to "lock" the splice. I cut a short section of rope and pulled strands from that to sew all of the fixed eyes on my Whoopie slings.
Note that on their Whoopie Sling pdf they illustrate the fixed eye using a splice that threads the rope through itself, called a "Locked Brummel". Using this method actually weakens the rope more than a plain bury.
A plain bury has the disadvantage that the bury can work itself loose under no load or low load conditions. That's the reason for sewing the tail end. The sewing doesn't contribute to the load carrying capability, it just keeps the bury from creeping out.
That is the only advantage of the Brummel method of threading the rope through itself. It "locks" the bury in place. Unfortunately, threading the rope through itself also introduces weak spots. I'm pretty sure that Smason derates the rope for their Whoopie Sling by 40% because of the Brummel and not because of the bury. But I could be all wrong about this.
A side note on the UCR and Sling "discussion". One of the reasons I opted out of the UCR method is that, if I'm doing that method correctly, I needed 2 fixed eyes on each end of the hammock:
- one fixed eye at the tree end for hanging on the Marlin Spike Hitch, and
- a fixed eye on the hammock end for attaching to the hammock or ridge line
I also then needed the sliding bury splice for adjustment.
That is 3 splices per hammock end.
For the Whoopie Sling method I only need 2 splices: 1 fixed eye on the hammock end and the sliding adjustable bury.
On 1/8" rope I use 10" for the bury. The recommended 3.5 fids works out to 9.6" which I just make 10" since it's easier.
So for the Whoopie Sling method, the splices use up 20" of the distance from hammock or ridge line to the tree.
For the UCR method, I personally would need to use 15" and maybe 18" for the adjustable bury. The fixed eyes would still be 10" each. So the splices on the UCR method would be a total of 35" to 38".
So overall for the Whoopie Sling method I lose 40" between the tree span to splices and for the UCR method I lose 70" to 76" to splices.
Now For the Whoopie Sling method I could comfortably reduce the bury to 6" or 7" for the adjustable bury since the bury has forces exerted on both ends and I don't "lose" any of the bury length. I could not do this on the UCR method.
I use a 119" ridge line on my Bridges, so with the Whoopie Sling method and "losing" 40" to the splices, my minimum tree span is 13' to 14'. With the UCR method my minimum tree span is 17'.
I prefer a 14' to 16' tree span.
Thus two factors pretty much ruled out the UCR method for me:
- force on only one end of adjustable bury splice needs a longer bury and is more finicky in use, and
- the greater minimum tree span
Just my personal bias between the two.
Those who sacrifice freedom for safety, have neither.
Do not dig your grave with your teeth. (Unknown)
I guess my scenario is a little different. I use an end channel hammock that's a bit shorter than most, and I wanted the ability to use trees up to about 24 feet apart.
Another thing I'd forgotton to mention in past notes was that my whoopie sling would often pop off its tree-end toggle during adjustment, under light loading. The fixed eye of the UCR eliminated that concern for me. I'm sure that using a marlinspike or a longer toggle at the tree instead of my tiny (1-1/4") ones could have avoided the issue, as well.
On a side note, in either system the free part of the extra line works fine as a drip loop. Nature gave me a 3:00 AM test this past week and the drip lines kept my hammock dry. The water never even got to my hammock-end toggles. ...and I'd forgotten how loud Virginia songbirds get at 5:15 AM.
Both TeeDee and Frawg have designed modular suspension systems that allow them to switch out components to suite their specific needs. This gives them great flexibility and adaptability for their hammock setups.
When I first started following their lead I, too, made modular components: stand alone slings with eye splices at one end and whoopie loops or UCRs at the other. Everything buried and neat and very strong, but also involving more work to make.
I was getting ready to replace my hammock lines with one of my fancy slings. The eye splice bury took up about 10 inches of line that was un-usable (couldn't tie a knot with it or make a bury there.). Add 10 more inches for the whoopie bury and a couple inches to separate the burys and suddenly I have effectively made my hammock 2 feet longer at each end.
The hammock trees in my backyard are exactly 12 feet apart. My hammock is 10 feet long. Adding 2 foot long whoopie slings at each end... well you do the math.
Then I realized that I had been comfortably using rope tied to the whipping of my hammock for more than a year, a knot tie by the manufacturer. I never worried about that knot. It had always held, never slipped. And even though the eye splice of my sling was stronger and more aesthetic- well it wasn't really necessary.
So I simple added the 10" whoopie bury to the line tied to the hammock and by combining the knot with the whoopie got what I wanted (simple adjustability) in a shorter distance. Yeah, it's not as aesthetic, but it is plenty strong for my needs, works, and fits the space I have.
To quote TeeDee: "what's not to like."
OK , I got sore fingers now, thanks. Ran a whoopie sling thru some four strand paracord, holds well. No, I wont hang from it, but I did get some good practice fighting a needle and string. Took one strand out every few inches, leaving outer sheath intact, to create a long taper. Threaded the taper end onto needle, and carefully threaded needle thru sheath, allowing about 20" of good cord. Pulled taper thru and milked the "good cord" all the way past my exit.
I'm curious how well it will undo in cold, wet conditions? Might freeze solid and leave you trying to thaw out a foot or two if icy rope. Fid length was four inches due to needle length.
Ambulo tua ambulo.
probably not any worse than a wet knot, plus if you are using toggles or biners taking down would not be a problem.I'm curious how well it will undo in cold, wet conditions? Might freeze solid and leave you trying to thaw out a foot or two if icy rope.
I think it is probably a lot easier with hollow cord single braid line. No fighting the needle, No tired fingers.