Two Strand Stirman Running Bowline

stirmantrees

Well just in casei brought along this variety I went ahead and just named it. I have used it for many years and it has stood the test of time. I have rigged branches/ logs probably up to 2000 pounds with this. Mostly light stuff though. I started doing it approx. 10 years ago or so because i was getting sick of tying lowering and tag lines over and over again. It has not failed me yet and i just want to pull my weight around here. You all bring such great ideas. I hope this one makes everybodys lives go easier.
Maybe the Masters can analyze it and tell us if there is any problems.

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Eric Frei

So your lowering line is 2 lines? Is that what you're on about?

I bet that's a Leopard tree (Ceasalpinea ferrea)

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kiwi_tree_steve

yeah im not sure what he on about about it being special.... not sure what application i could use it to my advantage...

tree ID wise.... i rekon... Platanus

American Sycamore is a of platauns species aren't they?


ps. Clean ya rope ends, a bit of electrical tape before you cut it, and a lighter does a trick!

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"You have to feel and touch a tree" Shigo

kiwi_tree_steve

re read, and i think this is, 1 line is the lowering line, and the other line is a line to direct or pull around by a groundie i guess.....

im not sure i'd doo it this way, would like to know others opinions on it tho,

normaly each limb / situation chooses what tieing combo ( tip, butt, balance, ect) i use to lower a limb. never had a tag line tied at the same point as lowering once again, leverage and targets are normally the catyalst for were the tag line goes.

steve

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"You have to feel and touch a tree" Shigo

stirmantrees

lot of stuff does not need to be tip tied etc. all i am getting at is that it takes me half the time to tie two knots. big time saver. dont be silly and do this if you need to tip tie, duh.......
thanks. i new somebody would comment on the tail end of that rope. jeesh

MTS247

It's ok i knew what you ment

Eric Frei

I can think about a few things like this, are you trying to pull the knots apart? Is there a possibility that the pull line could in fact exert enough pressure on the lowering lines bowline eye that the lowering line loosens enough to slip off the branch end?

I would personally have to say that if I were assessing for a qualification it wouldn't go down as correct because knots should not be loaded like that. If both ropes were loaded in the same direction I would still frown on the practice because are both ropes clamping the tree or is one clamping the other etc, also is rope on rope where there is cross loading going to increase strength or decrease strength? Obviously decrease so I think whilst it may work in light applications it's one of those things that develops into a habit which can potentially become a bad habit in wrong application.

For a tag line we often use a rope with a steel screw gate biner in the end, couple wraps and click you are done.

Not busting your balls, can see the merit, however for qualification assessment I would not approve of the practice as it doesn't comply.

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MTS247

I would like to see how it looks after it has been loaded befor i would use it. but looks fine for smaller stuff. If it works use it.

Biner on end of rope with wraps *Fail* "side load binner"

Eric Frei

What is the side loading gate strength of a 72Kn steel biner? 12Kn

When wrapped in this fashion there is also a significant loss of tension on the biner.

Remember, this is a tag line and is not interfering with the load line.

How much force can a person exert on a tag line? Maybe 100kg so we are well within scope.

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stirmantrees

i think most stuff we do day to day is small stuff, but i have loaded it pretty good and it has held well. wheres that rope guy on the other thread, im sure he would have something to add.
both knots always seem to tighten nice and hold well.

i know something else that is good in lighter applications but can become a bad habit in other applications

MTS247

You said it, its well within scope.
Just as using the "Two Strand Stirman Running Bowline" to lower small branches "may" be well within its scope.

Im just not sure using this knot in an assessment would deserve an NC on a rigging assessment, if it was overloaded or broke then hell yeah.

stirmantrees

im sure a little inspection as we should all do anyways could make sure the knots are set well.
I guess we need to understand the what could go wrongs. I have a feeling its a good system but that would be conjecture to a degree. Scientifically speaking ofcourse.
maybe there is a way to tie it so that it does apply forces appropiately
It works, so i use it.
its passed my real world in the field test.
why dont you try it ekka?
you might like it
come on just once
your not the only one with good ideas.

Eric Frei

It fails I feel for reasons that I have mentioned. Sure in light application I dont envisage issues.

Generally I dont tie knots up the tree, I use knotless rigging. I also dont like tag lines on the same point as lowering lines, becomes a "tug of war" on the lowering and guidance lines rather than positioning the cut piece. Many times when we lower the tips come down first and people grab the tip and walk away from the tree laying the piece down with the butt pointing in the wrong direction. So then we want the butt pointing away from the tree ready to be dragged out and into the chipper so we put a tag line to help achieve this.

As the tips touch the ground we try to pull the butt over into the desire direction, pull on the tag line release on the lowering line. When the point they're attached to is the same place it makes it a little uglier to do IMHO.

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Victor Lindsay

To me, a tag line is for control, and you reduce it's control when tied to your rigging point. And what EKKA, said.

moray

Viewed from the point of view of getting two knots for the price of one, I think it is a cool idea. The worry that the tag line and the lowering line are somehow interfering with one another seems like a complete non-issue because neither line goes directly to the knot. Both lines are perfectly parallel when they enter the knot no matter how they might be oriented when they enter the loop. Whether or not the bowline is rendered less secure because it consists of two parallel lines is a practical question, but 10 years of field experience seems like plenty to rely on. The fact that this is configured as a running bowline also protects the knot somewhat. All in all, pretty sweet.