After now getting another jam on a .70 inch diameter object with a 3/16 inch line, I wouldn’t describe it as jam-resistant.
The smaller object was .312 inches.
See http://notableknotindex.webs.com/friction.html - simply take the end under the loaded cord at the top of the support bar. It is the friction that hold it, not the shoulder. The positive feedback of the load gripping the cord at the top of the bar is amplified by the turn. With most agricultural cordage onto galvanised pipe the CF is more than adequate.
Derek
???
I’m going to have to see a picture of this actually working, and preferably one without hot glue. 
I think you’re describing Round Turns plus a Simple Hitch. That’s fine, but that hitch would not go in the number one spot!
For comparison, the Round Turn & Two Half Hitches is currently down at #11, while Two Half Hitches is currently at #4.
Doing some testing myself, I agree.
LOL, nice one Roo, but you know a single spot of photoshop is worth a whole yard of Ductape and hot glue.
Instead of relying on a picture of dubious character, have a go for yourself. I have ca 2" hot dip galvanised support tubes and generally I use a cheap two strand hempen garden twine. simply wrap it once around the tube and tuck the end under the turn at the top of the pipe. As you own site explains, if it holds one pound, it will hold a hundred due to the positive feedback from the construction.
It was your very self who introduced me to this vital mechanism of knotting, an aspect that I consider second only to cogging in knotting functionality importance.
Derek
Nope, just a single turn with the end tucked under the turn at the top of the tube - exactly as in the simple turn image but without the crutch.
Derek
Figure-of-eight hitch: http://www.marinews.com/bait-presentation/figure-of-eight-hitch/606/
Knute Hitch: http://i300.photobucket.com/albums/nn20/s9mbilan/knuteHitch.jpg
Lighterman’s Hitch: http://i300.photobucket.com/albums/nn20/s9mbilan/Lightermanshitch.jpg
Gaff Topsail Haylard Bend: http://etc.usf.edu/clipart/58300/58374/58374_studdingsail_md.gif
Gaff Topsail Haylard Bend as demonstrated by Budworth: http://www.apparent-wind.com/knots/anchor-hitch/ab17.gif
Boom Hitch: http://www.stufftotweet.com/tweetthis/wp-content/plugins/wp-o-matic/cache/139a7_Boomhitch5.jpg
I’ll have to trust you not to photoshop.
As you own site explains, if it holds one pound, it will hold a hundred due to the positive feedback from the construction.I think you're reading too much into the capstan equation.
Instead of relying on a picture of dubious character, have a go for yourself. I have ca 2" hot dip galvanised support tubes and generally I use a cheap two strand hempen garden twine. simply wrap it once around the tube and tuck the end under the turn at the top of the pipe.Since this is not working for me, I'll have to wait for the photo to verify configuration and results.
Implicit in the requirement for non-jamming hitches is the expectation that these hitches would take loads that would jam other hitches, and not just the weight of a feather.
OK, No Photoshop, no glue, only friction.
I don’t think my tomatoes have read the capstan equation, but they all seem quite convinced that they are being held upright, and my beefsteak toms weigh in at about a pound per fruit, about 5lb per truss.
Derek
I can get that knot to hold securely only if it’s dressed like the Half Hitch shown in the list (or like a Timber Hitch with only one long turn around the rope). If you can provide a pic of this hitch in that type of dressing, then I can add it. This hitch is untrustworthy if it’s dressed how that website shows.
For the lesser known hitches, I need more than just links to websites. The web is loaded with misinformation. Provide a summary of your experimental results, how you use the hitch, why you like the hitch, etc. Your summary might be just two or three sentences. Otherwise, I’ll have to do my own quick experimentation, and that will be the only data I’ll have.
My camera sucks, but here is pictures of the figure-of-eight hitch in action. Once set properly, there were no slippage when lifting the 50kg barbell the rope is attached to.
http://bildr.no/thumb/1126144.jpeg
http://bildr.no/thumb/1126145.jpeg
The hitch doesn’t jam. It’s quik and simple to tie and it doesn’t use a lot of rope. It is more secure than the half hitch, however it should be treated with caution.
Yes, do you notice that’s like a Timber Hitch with one twist, instead of five or so twists?
I don’t want this to get to be too long of a detour, but if you look at ABOK #49 single hitch, you’ll notice that if the hitching object vanishes, you have a coil and not an overhand knot.
So, with what you are doing with your “shoulderless” ABOK #49, if your pipe vanishes, do you also have no leftover overhand knot?
+1 . Actually, IF the object’s allowed (with the special shape),
then a far better (more secure) hitch would be to bring the
end around the object below the SPart (as pictured here)
and then back to tuck under itself --a surer nip than the
one rightly regarded as dubious by Knot4U. (No, Derek,
I surely would NOT expect this hitch to hold much force;
there was a reason for the double blackwall h.
–doubts about the single. (YMMV) )
I did have a stubborn jam with your [i]Ossel Hitch[/i] you have shown when used on a small object. But since the discussion is focused on larger objects, maybe that's not relevant.
It’s highly relevant; as I’ve said elsewhere : the ossel hitch
is only effective qua ring hitch (and jamming is one
desired quality for it); it will spill on spars & piles.
Btw, as the gnat h. is --like many of the structures here–
what I call not a “hitch” but “noose hitch” that uses the
marlinespike h. knot, it can be revised so that it in fact
uses an ossel h. knot --which is something to consider
in either orientation (of “tying away” or “tying towards”
the object (i.e., diff., resp., between 2 half-hitches & buntline,
of the clove noose-hitch)) .
–dl*
The snuggle h. should be replaced with a like
and 1-turn-simpler version of the groundline h.
–where the tuck for the latter is made in the
same direction as shown here for the former.
The tail becomes a means to loosen the knot,
which becomes more snug & well set than the
groundline hitch.
The pedigree cow h. should be replaced for the
better (not object-size dependent) improved cow &
better half --my improvement to the arborists’
so-named knot, which just denotes finishing with
a half-hitch around the SPart (as is done with
the clove, sometimes). Given the orientation of the
cow above, untuck the “pedigree” extension and
take the tail leftwards Over the SPart to tuck back
though the SPart turn’s nip AND THEN bring it out
between its own part (i.e., the reach leftwards) and
the collar of the cow to be nipped --nipped by
rope alone, no dependence upon a near object!
This should give a pretty secure lock, but not one
jamming beyond hope.
–dl*
Yes Roo, correct, if the pipe vanishes then all that is left is a coil.
@Dan
(No, Derek, I surely would NOT expect this hitch to hold much force; there was a reason for the *double* blackwall h. --doubts about the single. (YMMV) )
Have a look at the capstan equation on Roo’s site. For this hitch the grip is totally dependent upon the CF. If it is too low, then #49 will hold nothing, but if it is high enough, then #49 will hold until the cord breaks because it is a positive feedback system. A large proportion of the applied load is brought to bear upon the nip of the end against the pipe, stick, pole etc. This generates a modest gripping load of the end. This grip load is then exponentially amplified by the 360 degree turn by the factor of 2.7^(6.3*CF). While you might struggle to get a sufficiently high CF with nice slick polyester braid, hairy string and recycled baler twine against wood or hot dip galvanised pipe have a massive CF and so easily magnify to hold the load. And as you see, provided the CF is not load dependent, then this function is independent of load. More load, more tail grip, more friction…
The only reason for doubling the turns is to allow for lower CF’s - with two turns, this function becomes 2.7^(12.6*CF) thereby allowing cord to bar CF’s only half the level of hairy string to be effectively used - in fact with two coils I can use polyester braid against galvanised pipe with ease.
Derek
Edit typo
That sounds good, but I need a pic or at least one definitive name or ABOK#.
Otherwise, we’ll just have to wait around until I can make a pic and think of a name.