Prusik on cable

I usually use opposite threaded lags (as long as no decay is encountered while drilling--then you have to go all the way through, or use slings), then tension the cable very slightly by turning them both in. It gives you a better sense of how much tension you'll end up with, compared with any method of pulling the leaders together, IMO. Also, allows less drilling, and so less decay and a lower probability of stem failure down the line.

If you hit decay, you can install bolts (standard thread, not lag thread), and tension the cable by the number of turns you put on the nuts.
 

NickfromWI

Participating member
Location
Los Angeles, CA
A little test

So I did a little mock test to filter out some types of cords and hitches that might work to grab the cable. Here's a pictures of the cords that were used.

#1= 1/4" Yale Vectrus vectran single braid. Spliced a few months ago with a scrap that was about to get tossed. I dipped the whole thing in maxi-jacket coating and used it for a bridge for my harness for a few weeks before abandoning it.

#2= 3/16 Yale Vectrus vectran single braid. I spliced this about 3 years ago when I lived in NJ. It served as a friction hitch for a few days on my climbing line. Then it eventually found a home as the adjuster on my 3/8ths diameter flip line.

#3= 1/4" NER polyester 3 strand loop. Spliced about 5 years ago when I lived in Chicago. Never really used it for much....occasional light rigging.

#4= 5/16ths Samson Stable Braid- given to me by JPS when we were working with Fred B. in Colorado. Served as a hitch cord on my climbing line for a few months of careful climbing (to see how long it would really last). I don't use it for much nowadays.

So basically, went out and found a telephone pole with a guy line anchoring it in. I found one just outside my house, and proceeded to check each cord with a variety of knots. The choices were:

1: Many wraps (like what many call a "french prusik")
2: 3 wrap prusik (aka English Prusik)
3: 4/1 Distel*
4: 4/1 Schwabisch* (how DO you spell that?)
5: VT/MT- no. of wraps dependant on what the cord length would allow

The guy wire i found was a very taut piece of 3/8 1x7 (i think) wire.

I tied each knot- some carefully, some intentionally sloppy. My goal was to filter out a few cords and a few hitches. Each cord was tied, then pulled on with body weight. If it held, I would "shock load" it by yanking sharply on it to see if I could make it slip.

In the meager test, only one valuable piece of information was found. Every single cord, tied with every single hitch, no matter if it was tied properly or poorly, held very firmly and did not slip in any case.

So does this mean that it will work? Absolutely not. Surely the cable I was using has more "texture" after being exposed to los angeles air for an unknown time. A brand new wire will be more slippery and may not hold ANY knot. Also, I don't know what this wire was made of- and that factor could make a difference as to its "holdability."

Was this test a waste of time? Not at all. We know it MIGHT work now. And though I don't have any cable available to me now, maybe someone else can try the test at home, with actual cable that would be used to cable a tree.

Just thought I'd share!

love
nick

*(the coated vectran could only fit 2/1, and the stable braid a 3/1)
 

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Re: A little test

NICK! where are you getting the MaxiJacket coating? i've been searching for months now and no one seems to know what "rope coatings" are (at least in the arb supply stores, rescue stores, industrial supplies, etc.)

I emailed Samson and Yale, both declined to comment on the availability of their rope coatings to the general public.

???
 

NickfromWI

Participating member
Location
Los Angeles, CA
Re: A little test

I was given it while meeting at the factory one day. I don't know of any place that sells it, but I've never looked, either. I mostly use it for dipping exposed eyes, and a half-quart has lasted a couple years already and there's about half of it left.

Sorry!

love
nick
 

TC

Participating member
[ QUOTE ]
I'm looking at a scenario where the limb could break,

[/ QUOTE ]

Why are you even bothering to cable it then if it is that bad?
 

TC

Participating member
[ QUOTE ]

I am all for the non-invasive dynamic cables, but just wonder if they can sustain the load of a few thousand pounds (plus any dynamic forces that would increase that) being placed on them after 5 years out in the elements.


[/ QUOTE ]

Nick,

Don't be getting all steel cabley on us, your the rope fiend....check this out

Cobra 'Ultrastatic' Page 4 on the pdf.

I think you will like it.

Tensile strength 9 metric tons!! Dyneema.

C'mon Nick, forget about those steel cables. This means you can mess about with more ropes up the tree. Nice and light as well not like that filthy steel cable. You can even splice up the tree!!!
 

TheTreeSpyder

Participating member
Location
Florida>>> USA
Whut about an Icicle Hitch; as made by John Smith(not exactly like our climbing Icicle); or a Sailor's Gripping Hitch?

Legend has it John Smith hung from a tapered fid on an Icicle in a demonstration for IGKT(Ooops i see Gord already suggested Icicle).
 
Location
Philly
I used 5mm accessory cord in a pinch once for cabling and it worked great. Liked it so much that I used it ever since. Couldn't even tell you where that clunky, heavy metal grab is anymore. I use a french prussic, no problems.
 
Will a Prusik hitch work?

Both Heinz Prohaska & Franz Bachmann seem to believe that the structure
to use on cable is a friction hitch in which the cord reaches far and coils
back to the pull (like the venerable Rolling Hitch; opp. the ProhGrip/Blake's),
and show a knot in which the loaded end(s) run through a RING (implying
some benefit to a non-cordage entry structure).

Gary Storrick's site echoes Bob Thrun's citing of a "hitch series", and I'll
simply remark that seeking A hitch vs. using several in combination
might be a wrong approach. I just tried something akin to the structure
above, using the slickest rope at hand (a marine sheath & parallel cored
PP 8mm rope) on a thin (3/16?") cable--it slid, no matter ... .
But your Vectran should flatten & grip better than this PP, and maybe
your cable's thicker, to boot.

*kN*
 
MorExperimentinGoing on w/me, a bit:

I tried cable-hauling tape--an increasingly popular bit of cordage
in our GetWired days--, which is 1/2" wide, thin, very flexible,
and of lubricated polyester (you can feel the lube on fingers after
handling it); 1800# tensile is a common rating (same for a thinner
version of Kevlar--uncommon). (NEPCO & another maker, at least.)
A sling in this held well with my loading a cruddy 5-to-1 pulley
& 180# on THIN (4.5mm) wire rope.

Another method: with a tape sling, elongate it and roughly find the
mid-point, and wrap one (smaller) half around the wire toward the
haul, then counterwrap the other (larger--it's wrapping tape AND cable)
half; this was the instruction for some cable-hauling 4-armed strop,
as I recall (I remarked that rather than alternating over/under, it had
the arms wrap one at a time). Your sling's two bight ends will be what
you can attach to--hook, 'biner. This, too, holds well in cable-pulling tape;
and there's little distortion in the cable coming out of the hitch.
*** Oh, I should say that in wrapping esp. the inner spiral, I tried to keep
the bight of tape spread--i.e., laying on both sides to metal, not
one atop the other (doubling the width by wrapping with a bight). This
will give a longer, more nearly parallel helix angle. There were many
wraps.

---------

Yeah, I would think that a ultility pole cable would be relatively frictive,
and also would be straight--under tension throughout the hitch, not
with a loosEnd. (I'm kinda losin' my sense of personal & national security
to hear that a guy out apparently threatening to wreak havoc to our
electrical & telecommunications infrastructure ("Araya", closEnuff to A-rabic
this govt.'s work!) went unscathed by DHS. My confidence is shaken.)

*knudeNoggin*
 

theXman

Branched out member
Location
MD, USA
Nick,

You can find those cable "pullers" on e-bay pretty cheap now and then. I got one, I already had a good new one, but when I came across it by mistake on e-bay cheap, I had to buy it. Although I don't use these for cables within a tree. I do use these for installing "guy-wires".

I do a lot of cabling. A lot. Seems that I'm the only one in this area that does it regularly.

-------------

My suggestion:
Cable just like Fred Berkelh.... said above.

Fastest and best way to put the right amount of tension on the cable when the lags are all in to the right amount. No messing around with pulling things together.

I do the average 10 to 15 foot cable install in about a half hour.

I have a method that works very well. No mistakes, no re-doing anything.

And no pulling the limbs or leaders together to install the cable.

I'll PM you.
 

theXman

Branched out member
Location
MD, USA
How do you like this tight "V" crotch split?

Did this one, about 1.5 weeks ago.
 

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theXman

Branched out member
Location
MD, USA
You got it Mark.

Here's a pic of it next to the nice house. I'm drilling.
 

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theXman

Branched out member
Location
MD, USA
picture more of the crown.

crown was already light on the house side (good).

I thinned crown out maybe 1/5 before the installs.
 

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theXman

Branched out member
Location
MD, USA
old cable in the crown.

tree would have definitely split apart and fell on house if this cable was not here.

One side of the cable had the cable a little long though (picture).

Old cable was installed at a good location in the crown though.

Another cable in the front yard, was installed too low in a tight V double tree and was broken. It was the common soft cable though too.
 

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