Assisted pulling technique?

[ballibeg]

Taught this to use in self rescue scenarios on multi pitch climbs.

[Pete Mctree]

I find a 5 to 1 setup invaluable in all avenues of tree work. Mine gets used to raise limbs, pull stems over, pull out small hung up trees & even free stuck vehicles & chippers. There versatility is only limited by your imagination.

I constructed mine from the isc double sheeve pulleys & some 11mm rope. Not too expensive & has earned it's keep many times over

[Rich Rule]

I have a 5:1 system that was given to me by Dave the dog.

 

It was for hoisting the main sailed on a yaught.

[adamkaye123]

Yeah i was planning on using 2 double sailing pulleys and an old 50m line it adds so much and we don't have a winch so it would be great in the kit bag!

[Will Heal]

Or you could just use a couple of dolly knots/craters hitches and a few old carabiners.

[Haironyourchest]

Quite clever, 1st time i've seen that sort off thing.

 

In pracitce is it not easier just to have a hand winch/or tirfor in van?

I'd be worried that even with the increased load it was still not enough to pull the tree over and then u've no where to go

 

The average human male can put 35kg force of pull on a horizontal rope, given average ground traction. A three to one system would thus give you approximately 100kg pull. Thats a lot of messing around with rope and pulleys. One can buy a pocket size chain lever hoist for reasonable money which will give a 250kg pull. Just saying...

[Luckyeleven]

I was under the impression that the average man can pull his own weight...

[Haironyourchest]

I was under the impression that the average man can pull his own weight...

 

Funny thing the way the physics works - a given horizontal kg "pull force" will actually move more than the numerical weight, depending on the friction coefficient of the object to be pulled and the surface.

Thats why tirfors are rated like "3.2 tonne lift/5 tonn pull" this means that the machine will drag a 5 tonne concrete blck over a smooth concrete floor, but not lift it ( I think a concrete cube is the base metric, but I could be wrong)

An average man pulling on a roap attached to a load cell, will generate about 35 kg of force. Obviously if he had something to brace his feet against, like a rock, he could generate a lot more force, but in that case the pull would really be a lift. Its not about strength so much as traction.

The US Army vehicle recovery manual has some excellent illustrations and explanation of the dynamics of this idea.

 

 

http://www.lastgreatroadtrip.com/wp-content/uploads/2008/12/us-army-vehicle-recovery-manual.pdf

[jfc]

I can't believe I am the first one to say this but... I never needed any assistance 'pulling', however I am married now so those days are over!

 

Used 2:1 quite a bit. I had never used 2 friction knots. I like the idea of having one at the anchor end to allow you to reset the knot on the pull line. Thanks for the videos.

[bumble B]

Sorry. Wrong forum, embarrassing.