Author Topic: Jam-Resistant Hitches that Don't "Need" a Slip, from smallest to BIGGEST  (Read 23747 times)

knot4u

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Figure-of-eight hitch: http://www.marinews.com/bait-presentation/figure-of-eight-hitch/606/

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.
« Last Edit: March 12, 2012, 09:01:59 AM by knot4u »

knot4u

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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.

Hrungnir

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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.



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.

knot4u

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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.



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?
« Last Edit: March 08, 2012, 12:36:35 AM by knot4u »

Hrungnir

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Yes, do you notice that's like a Timber Hitch with one twist, instead of five or so twists?
That's right. One half twist more than the half hitch.
« Last Edit: March 08, 2012, 01:12:25 AM by Hrungnir »

roo

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Re: Non-Jamming Hitches that Don't "Need" a Slip, from smallest to BIGGEST
« Reply #35 on: March 08, 2012, 06:49:00 AM »
OK, No Photoshop, no glue, only friction.
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? 
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Dan_Lehman

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Re: Non-Jamming Hitches that Don't "Need" a Slip, from smallest to BIGGEST
« Reply #36 on: March 08, 2012, 07:55:49 AM »
I'm a little uneasy about including a "simple" hitch.  It's a little too gimmicky in that
it requires a special combination of hitching object and rope geometry to even begin to be possible.
Having a hitch that requires a special shoulder is like including a hitch that requires a narrow v-notch on some part of the post.

+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) )


Quote
I did have a stubborn jam with your Ossel Hitch 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*
====

Dan_Lehman

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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*
====

DerekSmith

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Re: Non-Jamming Hitches that Don't "Need" a Slip, from smallest to BIGGEST
« Reply #38 on: March 08, 2012, 09:04:21 AM »
OK, No Photoshop, no glue, only friction.
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?

Yes Roo, correct, if the pipe vanishes then all that is left is a coil.

@Dan
Quote
(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
« Last Edit: March 08, 2012, 11:28:21 AM by DerekSmith »

knot4u

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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*
====

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.

knot4u

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Knute Hitch: http://i300.photobucket.com/albums/nn20/s9mbilan/knuteHitch.jpg

I suppose that hitch only holds for the pictured application, and similar. That's too limited for the list.

knot4u

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Yes, do you notice that's like a Timber Hitch with one twist, instead of five or so twists?
That's right. One half twist more than the half hitch.

Instead of adding your pic in a separate entry, I added a comment to the Timber Hitch, thanks.

TMCD

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The Figure 8 Hitch is not a good hitch to include in this list if you're worried at all about security. I've actually been able to make it slip with my bare hands by giving it a hard yank and it's certainly not going to withstand any vibrations or jostling. Most of these other hitches are strong and can withstand a good amount of force put upon it, whether it be vibrations, jostling around or some kid grabbing at it.

The Clove Hitch I was talking about is listed as ABOK 1671, showing a CH with the WE half hitched around the SE for extra security. I think there's another reference in the book showing it in this fashion too, just can't find it right now. It says to tie this directly to a spar. This is a real good hitch to use as your anchor knot when tying a trucker's hitch.
« Last Edit: March 09, 2012, 03:28:07 AM by TMCD »

knot4u

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The Figure 8 Hitch is not a good hitch to include in this list if you're worried at all about security. I've actually been able to make it slip with my bare hands by giving it a hard yank and it's certainly not going to withstand any vibrations or jostling. Most of these other hitches are strong and can withstand a good amount of force put upon it, whether it be vibrations, jostling around or some kid grabbing at it.

We discussed the proper dressing above. With the improved dressing, the hitch is more secure than the Half Hitch as pictured in the list.

knot4u

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The Clove Hitch I was talking about is listed as ABOK 1671, showing a CH with the WE half hitched around the SE for extra security. I think there's another reference in the book showing it in this fashion too, just can't find it right now. It says to tie this directly to a spar. This is a real good hitch to use as your anchor knot when tying a trucker's hitch.

And because a Clove can be tied without releasing tension, this hitch can also end a Trucker at the second anchor.
« Last Edit: March 09, 2012, 03:56:06 AM by knot4u »