Rigging off another tree

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Mush

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What would the forces be if you use a rigging point on another tree 15 meters away ,swinging the branch with the rigging point at about a similar height to the branch being removed if the branch was 100kg
 
You're not going to have much room to let the piece run. 15m is pretty far away and from an even point it going to drop that much if not more. Once you lessen the angle a bit you will lessen the sideways forces and load on the rigging tree
 
Might be better off running the rope from the other tree throu a pulley, to where the branch is, tie it off below said branch, strap the branch to the rope with a caribener, cut branch and lower. I've down it with heavy wood. Little shock on trees or rope.
 
There is a lot wrong with the scenario presented.

It looks like folks are answering the load presented to the rope at the bottom of the swing.

What force does the 100kg piece present when it slams into the tree? 100kg coming to an instant stop?

This is large force and may result in pieces of the rigged and rigging tree exploding and creating shrapnel .
 
@ Del - how is it gonna slam into the other tree when the rigging point is at the same height as the limb being cut?
It's not like it is being speed lined into the other tree...after it reaches midspan it is gonna have to travel uphill, lol.
 
What force does the 100kg piece present when it slams into the tree? 100kg coming to an instant stop?

No such thing as instant stop.

F=m*v/t, where t = time to stop.
Say 1 meter is stop distance as branches crunch. distance (d) = 0.5*deceleration*time^2, F also = ma, etc....

Do the math, sure not enough to knock down the tree even if it hits the truck dead on.
 
That pendulum will swing for a long time if there is no brush to slow it down. About 4 seconds each way and it will go for a long time and probably slow down when it dances around and finally hits something. Be extremely careful, there is nothing you can put in its way to slow it down once it starts swinging. Jolly- where did you come up with 3 g's? I never learned a formula for that in physics but it would be useful to have.
 
Done it before, I put a rope/tag line on the piece which is wrapped round the branch below the cut, this will control swing to vertical then you can lower to ground, saves a crazy swing going all over the place

Sent from my SM-G900I using Tapatalk
 
Del, this is a good rig for certain situations. I did make certain assumptions in answering.

His cutting point is more than 15m off the ground, and there were no obstructions in the plane of the intended arc the piece would travel.

Yes on the assumptions. I've rigged such before and the piece will not likely swing in a single plane but is more a variation of a conical pendulum.

Also note: The load would have to have a release that was totally void of any side forces if the 'bob' were desired to swing in a plane. This is highly unlikely when swinging pieces of trees.
 
The trees and on the side of a hill so the cut branch will not hit anything and high enough to miss anything on the swing
 
The rigging point being at the same hight as the big branch and 45 ft a way makes this seem like a poor choice as a rigging tech. I doubt it'll pendulum much at first anyway unless the rope was pulled very tight. But many other options are possible useing that other tree. Broading your Horizons and looking at other possibilities will make this job go smoother depending on whats below and what your objective are. Think out side the box a little. Maybe a photo or better description will help give us a better mental picture, but it seem like your wasting a lot of time on a less then perfect solution.
Of course thats just my humbled opinion.
 
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