Originally Posted by
Ted
Today I set up and tested the HH ULBA using the Garda Hitch method that Trekkingnut has demonstrated in his videos.
The stock HH ULBA uses a suspension system of very thin (about 1/8"+ dia.) polyester sheathed 1,450-lb test Spectra line. I could not find any definitive info on the HF site about how this particular line behaved in the Garda ring system. The purpose of the test was to see if there are any issues with this setup combination.
Equipment:
Hammock: Hennessy ULBA with 2QZQ #3 zipper mod and no rainfly
Carabiners: C.A.M.P. USA Nano 23 Wiregate carabiners
Rings: SMC Aluminum Descending Rings, 1.5" ID
Test load (me): 150#, 5'-9" H
Finding:
Works fine but requires care to avoid excessive line wear and slippage. For safety, suspension line condition should be inspected before and after each setup of the hammock.
Summary:
The setup was as described by Trekkingnut: Tree straps around tree at conventional height. Carabiner clipped through both loops at the end of each strap with the narrow end down. Two SMC rings clipped into each carabiner. Hammock suspension line was run with one loop through both rings and a second loop passing between the rings.
Each free end of the suspension line was pulled through the rings to make the tension adjustment and seemed to lock fine. I did notice that it took a slight effort to pull the line through using only the free end, but found that if you use both hands, one to pull the free end while the other relieves tension in the line to the hammock, it flows through the rings smoothly with minimal friction.
At this point I sat in the hammock to see if there would be any slippage. There was not initially, but after I got up and readjusted the lines a few times, I did get some slippage. Once, I did not tug the adjustment tight at the rings on one end of the hammock and got a semi-fast ride to the ground.
I put a single half-hitch with a quick release on each end and again loaded the hammock. Again, no slippage initially, but after getting up and down a few times, minor slippage did occur at one end.
I put two half-hitches on each end and experienced no further slippage.
The system adjusts effortlessly and quickly as advertised, provided you use both hands to feed the line through the rings to minimize friction.
At this point I examined the Spectra and found noticeable wear on the polyester sheathing in the area where it had made contact with the rings. The sheathing was not penetrated but showed distinct surface fraying, with a spot two that looked like heat was the culprit. This was after maybe 15 minutes of repeated adjusting and loading the system. It seems that adjusting the line by pulling only on the free end, plus the few slippages I experienced under load, heated the line up by friction enough to cause the damage.
I concluded that unless you take care to adjust this system to minimize friction between the line and rings, it can quickly wear the sheathing and eventually compromise the line.
The Spectra has a stranded rather than solid core and I did not see any significant crushing of the line where it was clamped by the rings. Just a little deformation which should have no ill effect.
The SMC ring seemed to provide a reasonable bending radius for the small line size. A larger line size might help the problem since it would provide more surface contact area with the rings. Don't know the actual diameter of the ring stock.
Conclusion:
I am going to use the system in the field for a while and see how it does, taking the precautions I describe above. The fact that I could cause visible wear on the lines with 15 minutes of fooling around gives me some concern. I would expect to have to replace the suspension lines eventually because of the unavoidable friction needed to make the hitch work. As long as the sheathing is intact, albeit worn, I would not expect a problem.
Any thoughts or observations would be appreciated.
Reply With Quote
sorry!
Bookmarks