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Girth hitch thing for a lazy slackline anchor....
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By BrendanP
From Fort Collins, Colorado
Nov 28, 2012
Bringing the 90s to 2012 at Smith with an old Canon and poor footwork

For fatty trees where my 10' or 20' slings don't suffice, I just do this on one end of the slackline:

lazy slackline anchor
lazy slackline anchor


I seem to remember Freedom of the Hills saying not to do this for natural climbing anchors (and I don't) but I've been doing this with my slackline for a little while and I can't imagine the force on the carabiner or webbing getting up to ~20 kN even with the wide angle and higher tension on longer lines. Am I being a straight jong or is this acceptable?

I DO realize that as an alternative I could wrap the webbing a bunch and just call it a friction hitch without multiplying the load but I'm not just dumb, I'm also lazy.

EDIT: I also use tree protection 99% of the time, esp when using the same tree more than once, this picture just happened to feature the 1%... so feel free to rag on me for it but know you're not teaching me a lesson.


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By willeslinger
From Golden, Colorado
Nov 28, 2012
I was pretty bummed when they didn't greenlight my "Bourne Identity" style reboot of The Eiger Sanction. This was from the rough draft's first act.

Freedom just says that you shouldn't load the girth hitch back across the side of the loop the load baring end is threaded through, I don't think it matters here, but if you rotated the set up to the right in the picture and loaded the webbing directly rather than back across the biner it would be more in line with FOTH, but it's just slacklining, so I don't see you ripping a carabiner in half


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By Colin Kenneth
From Berkeley, CA
Nov 28, 2012
A well-spent Saturday night. All of the college kids are back, and even so, I had the best seat in Boulder to myself. <br /> <br />Bear Peak, from my front door to front door in just under 4 hours, including riding my bike each way to the trailhead, and 20-30 minutes at the summit.

Doesn't that twist your slackline anyway? That seems like it would be annoying.

Doesn't it take extra effort to come on MP and ask, and call yourself lazy than to take 3 minutes to put up a slackline well?


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By ROC
From Englewood, CO
Nov 28, 2012

The SAR method involves wrapping the tree multiple times before clipping the carabiner back to the load strand. It's called a tensionless hitch. It's considered full strenght because the friction of the material around the tree prevents the knot from ever being fully weighted.

You could do the same with the slack set up shown here.


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By BrendanP
From Fort Collins, Colorado
Nov 28, 2012
Bringing the 90s to 2012 at Smith with an old Canon and poor footwork

Colin Kenneth wrote:
Doesn't that twist your slackline anyway? That seems like it would be annoying. Doesn't it take extra effort to come on MP and ask, and call yourself lazy than to take 3 minutes to put up a slackline well?


I only have to make one post to Mountain Project versus hook up a slackline twice a week for the next decade. Just trying to streamline, baby girl.


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By Gunkiemike
Nov 28, 2012

From the look of the smoothed-out bark on that tree, I think you (or someone else) has failed to use padding fairly often.


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By TWK
Nov 28, 2012

From all the downed trees in the background, it looks like some slackliners have put on a few too many pounds in their self-confessed laziness . . .


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By 20 kN
From Hawaii
Dec 1, 2012

BrendanP wrote:
For fatty trees where my 10' or 20' slings don't suffice, I just do this on one end of the slackline: I seem to remember Freedom of the Hills saying not to do this for natural climbing anchors (and I don't) but I've been doing this with my slackline for a little while and I can't imagine the force on the carabiner or webbing getting up to ~20 kN even with the wide angle and higher tension on longer lines. Am I being a straight jong or is this acceptable? I DO realize that as an alternative I could wrap the webbing a bunch and just call it a friction hitch without multiplying the load but I'm not just dumb, I'm also lazy. EDIT: I also use tree protection 99% of the time, esp when using the same tree more than once, this picture just happened to feature the 1%... so feel free to rag on me for it but know you're not teaching me a lesson.

You should note that setup will reduce the strength of the webbing in most scenarios. This type of configuration is popular in overhead lifting applications. My purple load range colored overhead lifting sling is rated for 3,000 lbf if loaded end to end, or 2,400 when loaded in the configuration pictured above. You can do the ratiometric math and apply that to the slackline if you wish.

However, there is one serious issue I see. You have a nonlocking carabiner that is being pressed against the tree by the slackline. If that gate comes open, and it is pretty likely that it will if you use that setup often, then you could easily generate enough force to break the carabiner. If that happens, you will end up having a piece of webbing recoiling at you at NASCAR racing speeds, potentially hitting you in the face therefor providing you with a very expensive trip to the ER. Get a steel locking biner if you want to go that route.

willeslinger wrote:
it's just slacklining, so I don't see you ripping a carabiner in half


That is incorrect. The forces subjected to climbing gear while rock climbing are nothing compared to what is subjected to the gear when longlining. In fact, the loads become so extreme that as one progresses to longer and longer slacklines he or she will quickly ditch aluminum biners for steel biners, and shortly after, ditch steel biners for industrial overhead lifting hardware. Once you hit 100', you should be using steel components all-around, once you hit 200' you should be using shackles, round slings and webbing termination banana anchors. The slings I use on my slackline are rated for 30,000 lbs, and I use a 1/2" and 5/8" shackle to connect my webbing to my 32kN rated pulley system. You might think that type of hardware is overkill, but the standing tension on my line can be as high as 2200lbf. That is already as high as what you could expect on a factor two fall, except that the force is applied continuously, not for a millisecond!


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