International Guild of Knot Tyers Forum

General => Practical Knots => Topic started by: knot4u on February 02, 2011, 04:59:32 AM

Title: Trucker's Hitch: Reducing Wear on Rope
Post by: knot4u on February 02, 2011, 04:59:32 AM
This thread is for talking about ways to spread or reduce friction at the "sheave" of a Trucker's Hitch.  For example, one may tie a double loop right there to spread the friction.  Please don't hijack this thread with posts about how you'd rather just tie a plain single loop.  This thread is for discussing multi-loop knots or something else I have not imagined.  A multi-loop knot requires more work to tie obviously, but I figure if I've decided to tie a double loop, then I'm not in a big hurry.

If you use only a single loop in a Trucker's Hitch, take this opportunity to experiment with multi-loop knots or something else!  The application is unique.  So, you may be able to invent a knot that works great for this application specifically.  Here are some options:

(http://i51.tinypic.com/2j2ggso.jpg)
-Bowline With A Bight (ABOK #1074, tie by pushing a bight up through the rabbit hole, DIFFERENT than a "Bowline On The Bight")

-Double or Triple Butterfly
http://www.layhands.com/Knots/Knots_DoubleLoops.htm#DoubleAlpineButterfly

-A real sheave (pic by member Benboncan)
http://www.flickr.com/photos/benboncan/5360273853/
Title: Re: Trucker's Hitch: Reducing Wear on Rope
Post by: Hrungnir on February 02, 2011, 03:49:52 PM
I don't use double loops very often, but the figure 8 double loop is my favorite among this group of knots. Mostly because it feels more stable and secure. It's also easy to adjust the size of the loops.
http://www.abc-of-rockclimbing.com/climbing-knots/doublefigure-eight-loop.asp

I'm not quite sure a double loop would reduce rope wear though. It might create even more rope wear, because there's now two points causing friction. Has as anyone seen any research or has experience on this subject?

If double loop do cause less rope wear, it would perhaps be even more useful in the versatackle.

How about putting a thimble in the eye?
Title: Re: Trucker's Hitch: Reducing Wear on Rope
Post by: SS369 on February 02, 2011, 04:53:22 PM
I like the idea of using double loops as well. I described how I do in the thread about tying ladders on a truck rack. Another thing besides the load/abrasion reduction is that it also allows the separation tying in points if the rope for the T hitch is doubled tied (using the one rope as two).

I personally enjoy the use of the double butterfly loops.

As for the anti-wear properties, well, I think if you use the rope repeatedly and mostly in the same location/arrangement, you will get wear either way. Maybe less.

SS
Title: Re: Trucker's Hitch: Reducing Wear on Rope
Post by: knot4u on February 02, 2011, 06:49:52 PM
I don't use double loops very often, but the figure 8 double loop is my favorite among this group of knots. Mostly because it feels more stable and secure. It's also easy to adjust the size of the loops.
http://www.abc-of-rockclimbing.com/climbing-knots/doublefigure-eight-loop.asp

I'm not quite sure a double loop would reduce rope wear though. It might create even more rope wear, because there's now two points causing friction. Has as anyone seen any research or has experience on this subject?

If double loop do cause less rope wear, it would perhaps be even more useful in the versatackle.

Spreading the friction means less abrasion per unit area (i.e., less wear).  The friction is spread over the multiple loops.  If you tie two loops perfectly, then each loop takes half of the friction, and each loop takes half of the downward force from the single strand that's moving through.  By the way, the single strand moving through the loops is less of a concern because its abrasion point is not constant.  Anyway, the friction is also spread on the single strand moving through the loops.

Here's an analogy, which of the following would you rather not do:  pull-ups on a rope that's 0.5 cm in diameter or pull-ups on a rope that's 4 cm in diameter?  I'd rather NOT do pull-ups on the thinner rope because the forces and abrasions are concentrated on a smaller area of my hands, and my hands would tear.
Title: Re: Trucker's Hitch: Reducing Wear on Rope
Post by: Hrungnir on February 02, 2011, 10:08:33 PM
Quote from: knot4u
Here's an analogy, which of the following would you rather not do:  pull-ups on a rope that's 0.5 cm in diameter or pull-ups on a rope that's 4 cm in diameter?  I'd rather NOT do pull-ups on the thinner rope because the forces and abrasions are concentrated on a smaller area of my hands, and my hands would tear.

That's right! And I would also do pullups placing each of my hands in each loop, rather than both hands in one single loop. But what I wouldn't do is crawling on my knees (rope) through two tunnels (two loops) rather than one, which might be this situation.

I tried tying the setup, and I do get your point about double thickness and downward pull though. Seems like the figure 8 double loop is a good choice to get the right size on the loops :)
 
Title: Re: Trucker's Hitch: Reducing Wear on Rope
Post by: Dan_Lehman on February 03, 2011, 06:48:30 AM
Quote
By the way, the single strand moving through the loops is less of a concern because its abrasion point is not constant.

So one would think.  But Ashley gives a supposed traditional method
to break twine : pull it sharply over itself @#142-3 ; when I tried this,
just once, it was the moving cord that broke (!!?).  And one
rockclimber reported doing *StairMaster*-like sawing of a climbing
rope through an anchored 1" tubular nylon sling : the rope broke,
and a battered sling remained!  YMMV?
But, in any case, both parts might benefit from doubling/widening
the sheave.

You were right to question the ability to equalize eyes --I gave it a quick
try, and I wasn't happy with the result.
The simplest way --though hardly as quickly done & then shaken undone(!)--
might be to use a *doubled* Sheepshank (AT LAST!), as some
sources suggest nearly (but for the doubling, i.e.).

Now, the nipping turn might not get the twist of the eye to secure
it, but the doubled eye-bights also impede capsizing; the other turn
in the Sheepshank helps keep the enclosed TWO bight-eyes from
shifting and making one longer.  I.e., form your double-eye turns
around the had of the desired size, and half-hictch-nip each end,
using the one end qua double-eye for the trucker's hitch.

QED !?

--dl*
====
Title: Re: Trucker's Hitch: Reducing Wear on Rope
Post by: knot4u on February 03, 2011, 06:13:45 PM
The doubled Sheepshank is going to require some practice.  Now, I'm trying to figure out if it's possible to double a Span Loop, which starts off as a half Sheepshank (i.e., Bell Ringer).  Anybody know?  After a couple tries, I can't seem to tie a Span Double Loop.
Title: Re: Trucker's Hitch: Reducing Wear on Rope
Post by: Mike on February 04, 2011, 01:02:17 AM
What about just using a steel ring.  Just stick a bight of rope through it as you're tying your "bell ringer" knot.

(http://img546.imageshack.us/img546/599/dscn2589.jpg)
Title: Re: Trucker's Hitch: Reducing Wear on Rope
Post by: knot4u on February 04, 2011, 03:39:23 AM
I like the steel ring option, simple, relatively inexpensive, multiple uses besides for a Trucker's Hitch.  If I'm using expensive rope, I'd like to go with a non-rope option.  Here's a summary of non-rope options so far:

-steel ring
-thimble
-sheave
Title: Re: Trucker's Hitch: Reducing Wear on Rope
Post by: SS369 on February 04, 2011, 03:53:37 AM
Mike, knot4u,
if you use a carabiner in your pictured set up, you can hook into both loops and split the load on the loops and knot.

SS
Title: Re: Trucker's Hitch: Reducing Wear on Rope
Post by: Mike on February 04, 2011, 04:39:19 AM
Mike, knot4u,
if you use a carabiner in your pictured set up, you can hook into both loops and split the load on the loops and knot.

SS

I'll have to give that a try.  Sounds like a good idea.
Title: Re: Trucker's Hitch: Reducing Wear on Rope
Post by: Sweeney on February 04, 2011, 11:21:23 AM
Expensive but you could use a carabiner with a built in sheave - depends I suppose on the relative cost of the rest of the setup.

Barry
Title: Re: Trucker's Hitch: Reducing Wear on Rope
Post by: roo on February 04, 2011, 03:49:32 PM
Now, I'm trying to figure out if it's possible to double a Span Loop, which starts off as a half Sheepshank (i.e., Bell Ringer).  Anybody know?  After a couple tries, I can't seem to tie a Span Double Loop.
If you're looking for a multiple-loop approximation of the Span Loop, you could start with half of a fattened sheepshank (only make one of the half hitches):
http://notableknotindex.webs.com/sheepshank.html

and then complete the Span Loop:
http://notableknotindex.webs.com/spanloop.html

Or, if you have an affection for the sheepshank, you could explore the sheepshank double loop (http://notableknotindex.webs.com/sheepshank.html) shown next to the fattened sheepshank.

Title: Re: Trucker's Hitch: Reducing Wear on Rope
Post by: Dan_Lehman on February 04, 2011, 08:49:10 PM
If you're looking for a multiple-loop approximation of the Span Loop, you could start with half of a fattened sheepshank (only make one of the half hitches):
http://notableknotindex.webs.com/sheepshank.html

Bingo!  And this is not going to take Knot4U much practice, really.
Just form the (uh-oh) round turns (whew) and then cast half-hitches
(which look a lot like further (round)turns! :o) over each end; you
can figure out how close to position these, but it's the job of the
one towards the eye/hauling end to better keep the twin eyes in
good equal sizing.

Meanwhile, the old hands using the tried-&-true quick-twist and
so on have shaken their innumerable many knots free and are working
on fetching and securing their 2nd load of hay.  While we might
take consolation in missing this healthy physical activity, we'll
pay the price coming to the dinner table later --those who work,
first-served!
 :D

Might a Midshipman's/AWNING hitch-like formation of a two-turn
half-hitch nipping by the S.Part suffice for security of this doubled
eye, sparing the (lower, for the paradigm use) half-hitch, enabling
the shake-free aspect?  --i.e., make a 2nd turn, jamming this into
the first, for both stability & grip/nip?!   (haven't tried this myself...)


--dl*
====
Title: Re: Trucker's Hitch: Reducing Wear on Rope
Post by: knot4u on February 04, 2011, 09:05:16 PM
As I understand it, the half flattened Sheepshank can be turned into a Span Loop having 4 loops.  Or is it 3 loops tied properly?  That one is difficult.

Might a Midshipman's/AWNING hitch-like formation of a two-turn
half-hitch nipping by the S.Part suffice for security of this doubled
eye, sparing the (lower, for the paradigm use) half-hitch, enabling
the shake-free aspect?  --i.e., make a 2nd turn, jamming this into
the first, for both stability & grip/nip?!   (haven't tried this myself...)

I can't visualize this.
Title: Re: Trucker's Hitch: Reducing Wear on Rope
Post by: Dan_Lehman on February 04, 2011, 09:17:02 PM
As I understand it, the half flattened Sheepshank can be turned into a Span Loop having 4 loops.  That's a monster!

And not at all what *I* had in mind --rather, use one end of
the sheepshank for the twin eyes, w/o further modification.

Quote
Might a Midshipman's/AWNING hitch-like formation of a two-turn
half-hitch nipping by the S.Part suffice for security of this doubled
eye, sparing the (lower, for the paradigm use) half-hitch, enabling
the shake-free aspect?  --i.e., make a 2nd turn, jamming this into
the first, for both stability & grip/nip?!   (haven't tried this myself...)

I can't visualize this.

In that case it does!   ;D

It's simple : the bellringer's/sheepshank have a turn nipping
one end of a sort of hank of rope --typically one circle--;
make this turn as per awning knot, doubling it.  Some sources
in fact show this variation for the trucker's hitch, I think.

A sort of cross cow hitch vice the simple turn of the
trucker's hitch is also more secure; it doesn't shake free
and is not so quickly formed (I might form the c-cow
and stuff the circles into it, adjust & set).

--dl*
====
Title: Re: Trucker's Hitch: Reducing Wear on Rope
Post by: knot4u on February 04, 2011, 09:31:41 PM
It's simple : the bellringer's/sheepshank have a turn nipping
one end of a sort of hank of rope --typically one circle--;
make this turn as per awning knot, doubling it.  Some sources
in fact show this variation for the trucker's hitch, I think.

A sort of cross cow hitch vice the simple turn of the
trucker's hitch is also more secure; it doesn't shake free
and is not so quickly formed (I might form the c-cow
and stuff the circles into it, adjust & set).

Thanks, but I still don't get it after reading that 3 times.  I don't know what is "makes this turn as per awning knot", and I don't know what is a "cross cow".  Don't bother explaining anymore.  If I haven't already seen the pic, I probably won't get it with words only.