Slip Happens - Beckett cut through Amsteel

[PopcornFool]

Had a catastrophic suspension fail recently.

Background ... New DIY GE hammock I just completed a few weeks ago. New 7/64" Amsteel CLs I spliced myself at either end. New 1" UHMWPE straps I got from Jeff Myers at the trees. Relatively big guy (6'2"/240lbs). 3 day, 2 night backpacking trip to test out the new rig. First night, I used whoopies from CLs to MSH due to distance. No problem. Second night, I used Beckett hitch straight to CLs. Big problem!

I've used the Beckett hitch many times before on other hammocks using Dutch's UHMWPE straps on Amsteel CLs. Never had an issue. This time, the head-end Beckett slipped as I was (carefully) getting in the hammock. The friction cut clean through the CL. I quickly found myself on the ground (of course) and ripped my brand new 1.6 HyperD XL right where my center of gravity touched earth first (sore bum and major bummer). Dogbone to MSH took care of suspension. Duct tape on both sides of the hammock rip kept things together long enough for me to hang the final night. (Gotta love duct tape!)

Photos of the CL, straps, and duct taped hammock attached for the curious.
IMG_3419.jpg IMG_3421.JPG IMG_3420.jpg

Some quick forum surfing has enlightened me to the extra wrap technique when tying the Beckett which I will now apply religiously in the future. I plan try my hand at some alternative connections too like the J-bend and Lapp hitch to see how those work for me. I also find myself suddenly in possession of a large quantity of scrap material that I guess I'll be turning into stuff sacks or something. And I'll need to get more material for a new wide hammock. Oh well...

I'm not posting to complain though. Slip happens.

I'm mostly just curious ... has anybody experienced similar Amsteel fail with a slipping Beckett hitch when using UHMWPE straps? I haven't seen any other posts that mention it. References to slippage - yes. Cutting the CLs - no.

[nanok]

thanks for the pics, the one of the cut dyneema loop looks quite unreal. good to hear you didn't hurt yourself seriously.

i can't help with your direct question, as i haven't experienced this, but it's clear it can happen, and probably will. by any chance, was your hang angle the fateful evening a lot steeper (closer to the horizontal on the suspension strap)? this would explain the difference between first and second night, with a steep angle the weight in the hammock is multiplied on the strap.

the trouble is we're a bit too relaxed about these things regarding suspension of the human body above the (potentially unfriendly) ground. you see everywhere ultra light ultra thin straps, soft shackles and so on, which are "good enough" "plenty strong" and so on. ahem, no, we need load ratings, based on destruction testing. case in point, the becket hitch simply does not work in dyneema, it slides. well known fact, it slides at very trivial loads (compared to the line strength), this is a bit less of a problem with webbing, but still happens. at what loads does it happen in the combination you were using? unfortunately nobody can tell you, because nobody really tested properly. what we seem to do a lot in the hammock world is we just go for dyneema line sizes which are much thicker/stronger than needed, and then use knots and hitches which slide at 10% line strength, but it seems okay because 10% works out to 1.5 times our body weight, so when we test to see "if it holds" (very scientifically of course), we think all is well and expect it will be fine.

ahem. rant over, i guess i need to have my coffee. before posting. good to hear you wrapped it up safely, i think you likely did nothing wrong (no user error), and i advocate that hammock gear (suspension side) should come with clear break ratings in the intended configuration, ratings which should be based on destruction testing in the intended configuration (not estimations). but as an interim rule of thumb, remember dyneema on dyneema and knots is a combination of factors which should raise alarms in your head

[Phantom Grappler]

If a slip knot is tied in the bight or bunny rabbit ear, one inch from strap’s exit from becket hitch, then if the becket slips, slippage is stopped when slip knot bumps into becket hitch. The slip knot is too fat to pull through becket hitch.

I have shown this slip knot in at least one of my videos.
David Hughes
Phantom Grapplers recommended ties part 1 and part two, or another video

Suppose, you have backpacked ten miles, it’s sunset-dusk, and there is a slight drizzle, and you are hungry.
You tie the first becket hitch correctly
And on the other end of hammock, you tie a slipped half hitch instead! Hahaha

If, in the bight or bunny rabbit ear of slipped half hitch, you had tied a slip knot, that slip knot would stop suspension from sliding when it bumps into slipped half hitch.

Probably be hard to untie in morning, but it keeps your butt off the ground, and probably save all your gear simultaneously.

[Phantom Grappler]

If your UCR has a too short bury and or the prusik fails to keep other end of bury sheath taut, and now UCR slips.

Try this
I’ve not tried this, and I don’t use UCR in my hammock suspension

After setting UCR and milking bury tie a marlin spike hitch in middle of bury.

This might be enough to stop slipping.
Possible temporary trail fix to get you through a backpacking trip

[Phantom Grappler]

Why do I think a marlin spike hitch tied in middle of UCR bury, will stop slippage?

On another project, I was making a ridgeline for my hammock. Both ends of ridgeline are eye splice end loops. I use extra long buries, between just over a foot to 18 inches.

It was hard for me to figure how much ridgeline would be shortened due to long splices.

I wanted ridgeline to be an exact length, and choose not to use locked brummels. And I did not want to sew through the bury to keep it from changing length when not loaded.

I adjusted ridgeline to just over ridgeline length.
Milked the bury and tied an overhand knot in the bury...
Once hand tightened and hang tightened, the overhand knot stops the eye splice loop from changing size. The inner bury can’t slide inside the sheath part of bury.....even when not loaded, gripping strength good enough for me in hammock but not good enough for destructive testing or high altitude rock climbing.

It’s not a total guess to say a marlin spike hitch will stop a UCR from slipping. A marlin spike hitch is a slipped overhand knot held with a toggle.

[PopcornFool]

i can't help with your direct question, as i haven't experienced this, but it's clear it can happen, and probably will. by any chance, was your hang angle the fateful evening a lot steeper (closer to the horizontal on the suspension strap)? this would explain the difference between first and second night, with a steep angle the weight in the hammock is multiplied on the strap.

I'm confident that hang angle was not a contributing factor. I've been hanging for quite awhile and am also conscientious about double-checking my connection points as well (e.g. hitch loop under, CL on MSH knot and not the toggle, etc.).

I was using an EVO loop on the hammock CL to use as a pull tab to ease the Beckett Hitch release. Could this have caused the hitch to slip? I don't see how.

I can't help but wonder if the nature of the UHMWPE to roll up and basically act as cord on cord has anything to do with it. I know Dyneema doesn't take many knots well. But even with the slippage, I'm surprised that it cut the CL. I've never had a similar issue with my Amsteel whoopies on Amsteel CLs.

Maybe I should install two CLs on each hammock end. That way there's a backup if one fails. Slight weight penalty for peace of mind.

Am I overthinking this?

[PopcornFool]

If your UCR has a too short bury and or the prusik fails to keep other end of bury sheath taut, and now UCR slips.

I don't use UCRs except for my initial ridgeline for a new hammock when I'm first dialing in the right length. I've never used them in my suspension.

[uninjured]

Sorry to hear about your close call and loss. I'm afraid I can't offer much in the way of advice but I did switch from whoopies + MSH to becket hitch 2 weeks ago. I also bought UHMWPE from Jeff but mine is 2.9gpf and has black edges - not sure if it's dyneema or some kind of mix but I guess I'm in the same boat as you.

The first few becket's I tried I wrapped the wrong way - I think I wrapped them on the strap itself and I quickly went to (soft) ground - then I watched a video and saw you have to wrap it around the CL. First night I didn't double wrap and was OK (I'm ~200lbs) but then I remembered about the double wrap and have been doing that. Haven't had any slips yet (although only had 3-4 nights total). I also got Jeff's evo loops but haven't installed them yet and may not.

Thanks for posting this as I'm about to remake some dogbone extenders whereas I previously used only 4" bury but now will prob go 5-8" to be extra safe!

[BillyBob58]

Sometimes I fool around with J-Hooks and Becket, sometimes with the back up method mentioned in the OP. But, to be honest, old habits die hard, and I am still using the 1/2 hitch with back up- or whatever it should be correctly called - I just call it the Claytor knot. Still using it WITH THE ORIGINAL smallish nylon straps that came with it in 2007! I keep waiting for a failure, keep meaning to replace the straps. Admittedly, I don't hang over rocks or things that can easily break bones, usually. But, with my weight varying from 200-226 lbs(actually about 198 at the moment), I have never noticed a slip, and have never had much trouble getting it untied. And it most certainly has not cut thru my suspension. I use this slipped 1/2 hitch with back up with a lot of hammocks other than my Claytor. Never any problems, YET. http://www.mosquitohammock.com/hammockknots.html

[PopcornFool]

Thanks for posting this as I'm about to remake some dogbone extenders whereas I previously used only 4" bury but now will prob go 5-8" to be extra safe!

You're welcome. I know I've learned a lot over the years from others' experience. I certainly don't mind sharing my own.