- Location
- Chapel Hill, NC
That's slick Tom... I'm gonna have to play with it before I get it completely figured out but I like it.
knots
- Thread starter countryboy77
- Start date
tomthetreeman
Participating member
- Location
- Rhode Island
It's really simple. The first time I did it I was kind of impressed with the simplicity. It can be weird to untie (?) if you cross the loops over, though.
-Tom
-Tom
knudeNoggin
New member
[ QUOTE ]
while your bowline at best has a 40% reduction [www.allaboutknots.com/html/8_strength.html; at worst in a running or choked configuration? well lets use some conservative numbers at a 40% reduction in efficiency on a 1000 pound test line is a 600lbs working load in a straight line pull then reduce it further by choking it on it's self by a reduction of 22% and you come up with a working load limit of 468lbs and a total reduction of 56% in line efficiency. that makes you think about that running bowline.
[/ QUOTE ]
First you need to think about how these supposed efficiencies
get calculated and how they can (and cannot) be combined.
As for the 60% efficiency (I find it annoying to speak of "reductions"
-- it is direct to use break-strength %, which makes for simple
multiplication w/o subtraction), YMMV on test data for knots,
and maybe esp. for the Bowline. The strength of the Running Bowline
is something I think some arborist sources have, and I'd expect it to
be approximately in the range of a choker hitch. What these sources
might not state is where the structure breaks. If it's not at the knot
but where the line "runs" through the knot's eye, then bowline
strength is irrelevant, and you don't make the 2nd reduction for it.
in working application i had to sling two blocks to winch a lead off of a house a couple of months ago the slings were the same material and same length 3/4" tenex i had to use a running bowline on the bottom block to attach it to the tree and a cow hitch on the upper block.
[/ QUOTE ]
By "Cow hitch" do you mean one mainline bearing load with the
parallel end being a tied-off tail, or both lines taking load (as
would be the case for a ring-sling)? Where was the melting of
the Running Bowline --at the eye or in the knot? While with the
180deg (or I think you mean ZERO degree --rope making U-turn
through block, up/down) one should have doubled the load,
the force on the lower anchor can be greater than the factors
of rope angle suggest, depending upon block efficiency, by
a bit (i.e., it might take 1,100# force into the block to deliver
1,000 force up to 2nd block, at 90% block efficiency). Beyond
this point, might there be some difference in behavior resulting
from different diameters around which the two slings were hitched?
[ QUOTE ]
i edited because the third link did not work.
[/ QUOTE ]
FYI, I couldn't get to the allaboutknots page until I backed up to
the home page and went from there. (I don't think I mis-typed.)
*kN*
while your bowline at best has a 40% reduction [www.allaboutknots.com/html/8_strength.html; at worst in a running or choked configuration? well lets use some conservative numbers at a 40% reduction in efficiency on a 1000 pound test line is a 600lbs working load in a straight line pull then reduce it further by choking it on it's self by a reduction of 22% and you come up with a working load limit of 468lbs and a total reduction of 56% in line efficiency. that makes you think about that running bowline.
[/ QUOTE ]
First you need to think about how these supposed efficiencies
get calculated and how they can (and cannot) be combined.
As for the 60% efficiency (I find it annoying to speak of "reductions"
-- it is direct to use break-strength %, which makes for simple
multiplication w/o subtraction), YMMV on test data for knots,
and maybe esp. for the Bowline. The strength of the Running Bowline
is something I think some arborist sources have, and I'd expect it to
be approximately in the range of a choker hitch. What these sources
might not state is where the structure breaks. If it's not at the knot
but where the line "runs" through the knot's eye, then bowline
strength is irrelevant, and you don't make the 2nd reduction for it.
in working application i had to sling two blocks to winch a lead off of a house a couple of months ago the slings were the same material and same length 3/4" tenex i had to use a running bowline on the bottom block to attach it to the tree and a cow hitch on the upper block.
[/ QUOTE ]
By "Cow hitch" do you mean one mainline bearing load with the
parallel end being a tied-off tail, or both lines taking load (as
would be the case for a ring-sling)? Where was the melting of
the Running Bowline --at the eye or in the knot? While with the
180deg (or I think you mean ZERO degree --rope making U-turn
through block, up/down) one should have doubled the load,
the force on the lower anchor can be greater than the factors
of rope angle suggest, depending upon block efficiency, by
a bit (i.e., it might take 1,100# force into the block to deliver
1,000 force up to 2nd block, at 90% block efficiency). Beyond
this point, might there be some difference in behavior resulting
from different diameters around which the two slings were hitched?
[ QUOTE ]
i edited because the third link did not work.
[/ QUOTE ]
FYI, I couldn't get to the allaboutknots page until I backed up to
the home page and went from there. (I don't think I mis-typed.)
*kN*
kn it was a traditional cow hitch with a better half tied in the running end of the knot.
the melting point was in the eye of the running bowline.
the strength of the Running Bowline
is something I think some arborist sources have, and I'd expect it to
be approximately in the range of a choker hitch. What these sources
might not state is where the structure breaks. If it's not at the knot
but where the line "runs" through the knot's eye, then bowline
strength is irrelevant, and you don't make the 2nd reduction for it.
and why knot?
and where are these sources?
and when a wire rope splicer splices a rope with a splice that is not one hundred percent efficient then they take this into account when building the working load limits. to disregard that would be foolish in my opinion.
the melting point was in the eye of the running bowline.
the strength of the Running Bowline
is something I think some arborist sources have, and I'd expect it to
be approximately in the range of a choker hitch. What these sources
might not state is where the structure breaks. If it's not at the knot
but where the line "runs" through the knot's eye, then bowline
strength is irrelevant, and you don't make the 2nd reduction for it.
and why knot?
and where are these sources?
and when a wire rope splicer splices a rope with a splice that is not one hundred percent efficient then they take this into account when building the working load limits. to disregard that would be foolish in my opinion.
- Location
- Bluffton, SC
1/2in. rigging rope has a steel carabiner that I use with a half hitch. But anything big I use a bull rope with a running bowline and a half hitch
- Location
- walker louisiana
Rolling Bowline. just have to snach the tail out on the ground and I am pulling it back up. it is easier to tie than the bowline too.
- Location
- walker louisiana
also i think a half hitch on a bowline is not needed but that is just me. I have put quite a load on a bowline and never have had one come out. the place you need to worry about on a running bowline is where the rope touches in the loop. the bend raidus is so small that it takes away most of the stranth from the rope. In other words the rope will brake there where the bend is so small and your bowline will still be tied.
- Location
- Bluffton, SC
Yeah your bowline is not likely to untie but with a half hitch in there is spreeds the load out between the two knots so there is not so much pressure on just the bowline.
- Location
- walker louisiana
I think I did not understand you have your bowline tied on the wood and then you roll a half hitch on the wood above your bowline. That I agree with.I was thinking of you tieing a half hitch on the bowline it self. Sorry.
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