Becket hitch weight limit?

[Wandering_loaner]

Hi everyone. Long time browser, first time poster.

Does anyone know to what degree a becket hitch reduces the strength of the straps being used? Is it similar to the way knots weaken a ropes strength?

[DocTheo]

There's actually a fair amount of discussion about this; I've yet to see decent empirical testing on either the Beckett or the Lapp hitch with various types of webbing. Here is an article with a variety of knots in a variety of different types of webbing; none of which are the Beckett or the Lapp but some of which have a similar number of wraps. Remember that the reduction in breaking strength has to do with applying stress across the fibers of either your rope or your webbing rather than along the fibers - so the number of wraps in your knot and the area of stress that occurs laterally on the knot itself will come into play. A good general rule of thumb (which is used in rope tests with the Beckett hitch) is to assume that your knot will reduce the strength of your line by 48-52 percent of the rated strength - and ensure that your safe limit well exceeds this tolerance.

But as always, risk tolerance is up to the individual, and never hang higher than you are willing to fall.

[Phantom Grappler]

Everything weakens rope, not just knots
Knots weaken rope, splices can weaken rope, sun wind, rain and hardware can weaken ropes and straps
I like to have a safety margin somewhere between 5 to 1 and 10 to 1

Most suspension fails are due to user error.

[cmoulder]

This chart will give you a good idea... indicates sheet bend (Becket) loses 50%.

Which is why I'm kinda skeered of the 3.3g/ft blue polyester with 900lb rating... wouldn't take much of a shock load to exceed 450lb force with a heavier hanger.

[War Smeagols]

I’m 190 and used the Beckett hitch for a year with zero problems. Multiple overnights, several day trips, innumerable afternoon hangs in the yard… then I come on here and see all this slippage by people lighter than I. For the past month I’ve been using the J-bend instead just from being freaked out by all the stories.

[cmoulder]

I’m 190 and used the Beckett hitch for a year with zero problems. Multiple overnights, several day trips, innumerable afternoon hangs in the yard… then I come on here and see all this slippage by people lighter than I. For the past month I’ve been using the J-bend instead just from being freaked out by all the stories.

Highly dependent upon what webbing you are using! At one end of the scale, Kevlar 3.3 has extremely little slippage—none for me @170#— while the thin UHMWPE straps are much more prone to it. Dutch spider poly has very little, while some of the slicker polyester weaves have more.

Some years back I was doing a bounce test—*very* unscientific, but empirically quite useful—to test some ultralight spreader bars that I had made. I found that Kevlar did not slip at all with my preferred Lapp hitch, but UHMWPE would slip and leave that glazed-looking heat damage, and that Mule tape outright shredded the horizontal fibers.

My test tree for another knot, X-bend, but similar to the experiment mentioned above...

[rweb82]

I generally fluctuate between 195-200lbs, and I've never had a problem with the becket hitch slipping using my white 2.4g/ft UHMWPE straps. I did test some sub-2g/ft. straps and found that those slipped under load using a standard becket hitch, but did fine with a modified becket or J-bend.

[nanok]

This chart will give you a good idea... indicates sheet bend (Becket) loses 50%.

Which is why I'm kinda skeered of the 3.3g/ft blue polyester with 900lb rating... wouldn't take much of a shock load to exceed 450lb force with a heavier hanger.

take that with a huge grain of salt (aka: ignore it). any such information if the test data and methodology is not provided should be discarded at once.

at a very quick glance: the first chart is taken from some naval institute, and is said to be by testing manila rope of "up to 1 inch in diameter". aside from the comical precision as to what rope this was tested with, manila rope behaves very differently from modern synthetic fiber ropes.
the second chart on the same page is "stuff gathered from around the web". ugh.

on top of all this, knots behave very differently in webbing compared to rope, as people here anecdotally see (webbing in the same material might tend to slip less, for instance). but different fibers and different construction of webbing behave very differently from eachother too, as your tests have shown (thanks for sharing that).

having said that, i'm near the point to simply advise against the becket hitch being used at all for hammock hanging. it might work, yeah (and i have used it myself, and like it for various reasons), but in modern materials, and especially with lightweight construction webbing (like thin kevlar and dyneema) it seems like just asking for trouble.

this is the closest i could find as a current interesting resource with break tests in webbing. aside from the fact it doesn't include the becket hitch at all, there's a few other problems with it (sample size of 1, etc), but it does show how surprising the results can be, what factors influence results, and what proper testing involves

https://slacktivity.com/webbing-knots/

i am starting to seriously consider the possibility of building a test rig and getting some actual data. unfortunately it's costly and time consuming, to do it properly -- and it's the kind of thing which is useless if done any way but "properly" (so i'm still just "considering"). i do think we need it though

[War Smeagols]

I’ve been using UHMWPE the entire time with no problem. I don’t really want to shock test it. I tried the modified Beckett but found I could get a more consistent height out of the J-bend. I’m considering picking up some Warbonnet Beckett straps that are a fraction heavier than what I’m using but make have some more aggressive texture.

[Phantom Grappler]

It would be interesting to see number pounds of pull will break various commonly used straps while tied with becket hitch, Lapp hitch, becket hitch with extra wrap.
But if all the tester does is tie each knot exactly as shown on knot apps, without then dressing the knots and hand tightening them real tight, then those knots will fail at much lower pounds of pull.

There are many hammock campers, regularly and successfully using the above mentioned knots.
Those knots are passing field testing.
While there have been some fails, I believe almost all those fails are due to user error.