I am using a one inch nylon rope and already I have pulled the knots so tight I had to cut the tree on both sides close to the rope and
bust the tree trunk out of the center of the rope wrappings.
I have a few books on knots in my bathroom and keep two sizes
of cord dangling from the shower curtain bar so I can practice knots
while on the throne but none of my books give precise info as to
how easy the knots are to untie when pulled hard.
I back the truck up to the tree and tie the knots with about
30 or 40 feet slack and then I get a running start with the
truck to jerk the trees out.
I guess that means we are talking about some kind of hitch
or loop that can be tied around an object with at least two turns
so that the rope can grip the tree trunk tight without slipping
up the tree under tension.
I sure wish all the rope knot books and charts would list a numeric
rating of anti-jamability for each knot.
There might be 6 or 8 thousand pounds or more pulling on
these knots and in one instance I managed to tie a water bowline
around the tree where I had the loop making two turns and I had to beat the knot apart with a hammer after pulling the tree out.
In another instance I put six or eight half hitches spread apart
after putting two turns around the tree but the bottom two
half hitches slipped onto each other at the tree surface and
I had to cut the wood out of the knot to save the rope.
I thought my having a few books with hundreds of knots
in them would prepare me for jobs like this but they just
tell how to tie them and where they are commonly used
but not necessarily how easy to untie when really pulled hard.
I would recommend many wraps around the tree initially to reduce the force that will end up at the knot itself. I have done this before using a bowline tie after at least four wraps.
Stretch the rope first before to set things and then proceed with the rest of the process, if you think it safe.
Of course the higher on the tree you anchor the rope, the more leverage you’ll gain.
You might consider ducking behind the seat during the operation.
Ropes are somewhat elastic, even the large diameter ones!!!
This sounds serious --jamming a water bowline in 1" rope,
no less !! (But we should wonder at how you dressed
& set that knot --it shouldn’t jam, if the collar isn’t drawn
tight around the S.Part.)
We should also wonder What’s going on at the truck end?
–i.e., how is the rope secured to the truck (such that you
are not complaining about that connection)?! --a spliced eye?
When I started reading your description of multiple half-hitches
I was thinking “Ah, there’s a solution” but thinking that they
would be tied on the tree itself, not to make a noose around
the tree (so, sort of like an extended clove hitch).
You seem to have the right approach : of trying various things
that incorporate turns around the tree for gripping. Here’s an
idea in this scheme : tie a Prusik hitch around the tree (and you
can, since you’ll be tying it with an end not a closed loop, bias
the turns to have more low and maybe just one high), and tie
off the tail to the S.Part with a turn/half-hitch backed up
(“guarding”, actually) by a rolling hitch (i.e., the prior turn
will take more load and so guard the knot from so much). The
broad collar of the Pruisk should prevent that from jamming,
and the essentially loop-making HH-guarded rolling h. should also
be okay.
Alternatively, you might try this “guard” structure by putting in
one or two turns on the tree itself, backing it up (finishing the
hitching) with a rolling hitch (or extended clove hitch)
–similar in purpose to the commonly used HH + running bowline
of arborists when dropping cut wood.
As for the water Bowline jamming, I think if I as a human were proportionately larger and stronger to match the one inch nylon
rope, I might have been able to push the lowest curve of the rope
below the tail down the main part of the rope to begin the loosening process with my fingers. As it was with the tail of the rope coming out between the curves of the rope and giving a good rope surface to beat on, it only took a couple of whacks with the hammer to begin the loosening. Once you get it to move a 64th of an inch it gets easier
and easier. But it was still hard enough for me to want to try
another kind of knot considering I had to use a hammer.
BTW, I think I dressed the knot pretty good. It was snug and tight and looked organized.
At the truck end, I put three turns around the ball hitch overlapping from underneath to make it tighten on itself
then I wrapped the rope around the trailer hitch extension bar
6 or 7 times and then I tied it all off with two half hitches.
That end of the rope came apart easy when I was all done.
I am a little embarrassed that I did not put a fancy loop at
the truck end of the rope but 8 or 10 turns with a few half
hitches never failed me. Not pretty but works.
Actually the trees I am referring to are large overgrown bushes
with the trunks at ground level 3 to 5 inches in diameter so
there is not much distance the rope could slide up the “tree”
before all the branches separate. The holes in the ground
after root balls pop out are about 15 to 18 inches in dia.
This is a lot more fun than with a shovel and axe.
I’ve been looking through my books in the “hitches” chapter
and I dont really see any knots that assure ease of untieing (sp)
other than the many that use slip knots. I found this project
pulls so hard that I dont think I could pull a slip knot tail out of
the jam so that approach is out.
Whatever I do , I will use more turns around the tree trunk
to lessen the stress back to the knot. Good suggestion there.
Dan, I am trying hard to decipher your further suggestions and thanks for them. I am left to wonder in the real world there must
be lots of applications where folks tie off very large things with
big rope that have to be easy to undo.. Ships in harbor come to mind.
This is my first post on IGKT but in the interest of safety I cannot fail to reply to this post. Please be advised that many people die every year from nylon rope that has parted under load. Make sure no one is within the circle of danger.
I have had similar problems yanking on barely movable objects. My answer was to tie a bowline to a clevis of sufficient strength and use chain to make several round turns (no knots or you will regret it) then run the chain through the (heavy) clevis and hook it back onto itself. No problems. the bowline is tied to the pin on the clevis so if it jams just pull the pin through the bowline which should give you enough slack to force it to relax. I’ve never had that happen even when breaking the rope. You can pull round pipe vertically out of the ground using this technique given sufficient force. Think hydraulics.
Hmmm, this sounds within range of having that “collar”
drawn TOO tightly/snug --and that’s what one needs
to push back, to untie. Esp. as the water bowline
has a 2nd “turNip” to secure the legs of this collar
bight, and to take load from the eye, you should be
able to leave the collar adequately UNtight, even loose.
(Some of what one can see in photos of yachting bowlines
is darn impressive (one might read “scary”) of how large
& open & UNsnug that collar is!?!) And the two turNips
of the water bowline need not be snug to each other,
like a clove hitch, but themselves spaced comfortably.
(Some old books show them way apart.)
I CONCUR IN THE WARNING RE ROPE RUPTURE,
and especially nylon. I recall reading one anecdote about
one off-road truck trying to pull another one that was stuck,
and using webbing (which is LESS stretchy than rope),
and securing to a ball hitch : there was a bang, and the
ball hitch separated and became embedded in the stuck
truck’s engine!!! ouch, big time.
Again, one quick idea is to tie a rolling or Prusik hitch
to the object (idea is to have more turns for not only grip
but to make the crossing part (collar) of the knot all the
less liable to jam --too many parts to cross over, vs. clove),
and tie off the tail with a half-hitch (turn), maybe another,
or a 2nd full turn, perhaps jammed up into first as for
the midshipman’s hitch --sometimes rolling h. is shown
thus–, and then tie off tail to close your loop/eye with
a rolling hitch (the prior structure taking off load
from this.
THAT will be not so good, if your rope is so stiff as to resist
making the turns around itself for the tie-off “turNips” and
hitch; but, otherwise, it should do okay.
I agree with turns around the tree and little knot as you can get by with. It might be daft, but the first thing I’d try is a round or turn or two and a timber hitch. It’s not usually shown for pulling in that direction, but you can take an extra twist or two with it and if you set it to one side (the correct side) it cinches up tighter as it’s pulled to the center. It might come loose, but you’re not jumping off rocks with it. This not a different philosophy than that already said. The timber hitch is kind of half way to a cow hitch and a prusik is basically a cow hitch with extra turns, but those require some knot at the end and the timber hitch holds pretty firmly basically without really a knot at all. The twists at the end create friction and are held down by the friction, and they come loose easily when you stop pulling.
