WIP: Modular ultralight hammock-UCR quick disconnects
First of all, I'd like to thank SGT Rock and also some folks from the sailing community for their innovations. (i.e., https://www.youtube.com/watch?v=Ch-bqE7OQZw and http://l-36.com/soft_shackles.php?menu=4 )
Let me also say, that I by no means endorse this as a safe way to hang, or think that this is for everybody. If you decide to copy my setup here, you do so at your own risk and are responsible for your own safety. (In the wise words of SGT Rock: "You're gonna die!!!") Your life is in your own hands and I am in no way responsible for any injury or death that might result from copying my setup.
Furthermore, a lot of you are going to think I'm nuts, and dislike this setup, which is fine. HYOH; I just thought it would be fun to document this crazy idea and its implementation and its evolution.
This system, both sides including tree huggers (4' kevlar from Dutch with loops on both ends) UCRs and hammock leaders, weighs about 1.75 oz or 52g. That's 26g per side! (But, I'm thinking of getting a pair of 6' huggers and going with one long and one short hugger for more flexibility.)
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The UCRs are made from dynaglide (from Dutch) and are color coded to allow one to distinguish between head and foot ends. Once attached to the tree-huggers, each UCR and hammock leader provides just under 6' (71") of length, *NOT* including the length of the tree-hugger. This includes all line shortening due to buries, larks heads and other knots/connections, but excludes the tree-hugger length.
The outer portion of the tree-hugger is on the end that connects to the hammock. (This is the portion made from the shorter line.) The longer line of the UCR currently has a fixed eye (buried loop with locking brummel) which attaches to the tree hugger with a larks head/square knot through the one of the loops in the kevlar straps.
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The other end has a short backsplice-bury with a very short taper, and exits the UCR bury pointing towards the hammock.
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This means that the adjustment point of the UCR will always be close to the hammock, allowing for adjustment from underneath a tarp. Furthermore, the UCR tail exiting the bury can act as a water break. (You might want to tie a half hitch or clove hitch around the main suspension with the extra slack to help convince any trickle to run down the dangling slack.)
In general, I really don't trust taut-line hitches/rolling hitches (ABoK #1734 #1800 or #1856, in the context of a UCR the correct nomenclature IMO is rolling hitch because it is connecting to a different line) and much prefer the Midshipman's hitch/rolling hitch(2) (ABoK #1855/#1735) however I find it more difficult to tie with a very short line. (Or the Blake's hitch, but same problems...) For the time being I have the usual rolling hitch/taut-line hitch at the free end of the outer UCR line, fixed to the bight of the long buried line on the side running towards the tree straps. To compensate for my lack of faith in the rolling hitch (especially on dynaglide) I added some triple or quadruple wrapped Conair Poly bands (clear) that my wife uses for her hair to help constrict the end of the bury near the rolling hitch. This increases the friction and the bite of the unloaded end of the bury to help ensure that I don't end up on the ground in the middle of the night!
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They're pretty hard to see, since they are clear, tiny and weigh very very little, far less than a gram on their own. Here is what the packaging looks like. My wife bought these at CVS.
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For the UCR, I more or less followed the taper and bury lengths in SGT Rock's video, linked at the beginning of this post. I may have gone a little bit longer on the buries, and I also use locked brummels, rather than backstitching because it's a pain to get out the needle and thread when I have all my splicing gear handy.
Now for the quick connect magic: I was inspired to split the parts of the high strength soft shackle across different components. When building the UCR following SGT Rock's instructions, I added in a noose to the UCR eye-splice (in the shorter line) by passing the free end (eventually to be buried for the eye loop) through the standing end. To make the locked brummel to join the free and standing ends, I think I had to used a McDonald brummel, which is a technique for making locked brummels when the standing end is inaccessible, since I added this modification after I had already made the UCR. (Yay locked brummels--you can undo them!) Here is a picture of what the eye splice/noose looks like:
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And here it is if I open the noose to get ready to attach it to the connection point on the hammock:
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To attach a hammock, the noose is slipped over a two strand button knot which is tied in the middle of a doubled over ~17" piece of line. Once the knot is tied and dressed, and cinched tight, the tails are tapered ~3/4" and buried in the strands forming the loops. This creates a continuous loop, with a button knot tied in it, and exiting the button knot are four strands, all pointing the same way, but the free ends are buried, so it appears as two strands exiting the knot to form the loop. This continuous loop is then thread through the channel of my hammocks, and the button part if passed through the loop that exits at the other side, and pulled tight. Here is a picture of these button knot loops fixed to the ends of my ENO double-nest, before loading it with my weight:
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After hanging, the loop cinched tighter around the hammock, and there is more length before the button knot, which allows an easier attachment of a SRL.
Finally, the tree straps have soft shackles to act as 'biners so that they can be secured quickly. Unfortunately it is a little bit clumsy to use the soft shackles and they fall off easily when opened, so I'm going to switch to a grapling hitch, but using the buried two strand button knot, rather than a diamond knot for strength. Here is my current setup, where I made these soft shackles before I could tie the button knot, following these instructions instead. (They should be the same strength as the button knot shackles, just the stopper knot is uglier. Both this shackle and the high-strength shackle derive their strength because there are more strands carrying loads and the bending radiuses have been increased, an improvement over diamond knot shackles. I also really like the way that the free ends are buried and the elegance of the button knot.)
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Instead of these soft-shackles, I'm going to try out grappling-hitches with double strand button knots instead of diamond knots. This should help increase their strength.
Finally, on the portion of the UCR that attaches to the tree straps, i want to change out the eye-splice for a quick connect system, similar to hammock connection point. If I add a slipping noose on the tree straps, and a button knot on the standing end of the long UCR line, then for short hangs I can skip the UCR and attach the hammock directly to the tree straps. Also, if the tree straps get a lot of sap on them, I can prevent the sap getting on the UCRs by storing them separately.
What do you guys think? Am I crazy?
P.S. I plan to update this post with modifications I have made, and update this thread with successful hangs and any failures.
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Originally Posted by WV
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