Trip bowline; Inside hitch; Tarbuck knot

(Brian Grimley) wrote:

Trip bowline (new name?)
This uses a marlinspike hitch to make an adjustable bowline. The
interesting bit is that Marlow Ropes has the Trip Bowline form a Dutch
Marine Bowline rather than the usual Bowline when it is "tripped".

I'd like to understand why this form is favored by the those who do
--have heard (in KM somewhere) that some navy (Swedish?) does it this
way. In shock cord it seems more secure; and I surmise that it might
better resist capsizing (something I've seen in hawsers).
It's oddly put in Marlow's information, in that for the Bwl tied the
usual way, they remark at the end lying bewteen the legs of the eye
(in the loop vs. outside), as though that's important & desireable;
and they remark for the Trip that one should note carefully how to
tie it (well, wrt the Marlinespike form). It's a simple matter of
reeving the end through the Marlinespike's opening from one or the
other directions, but for some reason they get a different one than
they previously showed!?

Inside hitch

Which to most readers here is known as the Buntline Hitch.

(In one rope, Inside Hitch is 78% to Bowline's 63%
and in the other 53% to 44%.)

I take (haven't tried to confirm it...) "KT3" to be a Kevlar rope,
and this shows how knots affect that. As is typical for such data
about hitches, one isn't told anything about the nature of the
hitched object--was it a 50mm pin, or a 10mm one, or ... ? --and
what size ropes?

Tarbuck knot
It's just nice to see the Tarbuck hitch getting a little more
good press! :-)

But it's had some good press, and one might argue that it shouldn't
be so rosey. What's so special about it? --a Tautline H. with an
extra turn & a perhaps more secure finish: two things that really
should be obvious & suggested by the original. For security, though,
I think I'd favor putting a stopper knot in the end vs. the slightly
different tucking (which isn't made so clear in placement re other
parts here, and also in some other book(s) I've seen).
A caving acquaintance opined that the original asserted use of the
knot was based on dubious physics.

The press release on the site that announces that Marlow Ropes is
using polyester mooring rope to moor an oil rig in 4,420ft of water in
the Gulf of Mexico, frankly, takes my breath away.
[with spliced min. break strength of 1_932 TONNES (= metric = 2204.6#)]

They're aiming for providing such deep-sea mooring lines in jobs where
the expected service life is TWO DECADES! Naturally, owners of the
moored platforms don't care to have them become unmoored. There are
some impressive photos on one of the pages of some BIG ropes.
(www.marlowropes.com/offsore/news300102pic4a.jpg and others)
Try knotting THESE!!!

Elsewhere, in one of the papers (some under Towing, another under one
of the Mooring links, under Marine), they report doing a cyclic-loading
abrasion test between some small stuff of polyester & Dyneema: the
former abrades to failure in 981 cycles, the latter goes 3000 w/o much
damage (which they attribute in part to low coefficent of friction on
the steel pin)! In the list of rope-materials characteristics, Dyneema,
Kevlar, & Polyprop show up as pretty immune to chemical damage (e.g.,
100hrs in hydrochloric, sufuric, formic acids, caustic soda, and various
solvents, & hydrogen peroxide (reduces nylon to zilch) !

(The Marine site has pages more amenable to dial-up; the others have
stuff needing a faster feed! )

(-;

"Dan Lehman" wrote:

I'd like to understand why this form is favored by the
those who do --have heard (in KM somewhere) that some navy
(Swedish?) does it this way.

The Dutch Navy, according to:

http://www.realknots.com/knots/sloops.htm