Tree World - View Single Post - Are YOU teaching bad habits? How to stand up a limb

redstree · 5th November 2007, 02:59 PM

Trying to get back on track. As someone who has both been the climber working with a crane and the crane operator working with a climber all I can say is communication between the crane operator and the climber is extremely important.

Having a crane operator who is familiar with tree removals is also important. We were lucky to have our own crane, granted it wasn't the largest, just 85'(25m) and 5 tons(4.5 metric tons) but it did an awful lot of work during it's life time. When we needed a larger crane we rented one, with an operator. Fortunately we were lucky to have a few crane operators experienced in tree work in our area.

When everything is going according to plan it is just like a beautiful dance with the crane operator and climber each knowing what the other is going to do and anticipating the others moves. This sort of dance starts on the ground before the job starts with a discussion about the order in which things will be done.

As has been pointed out before, how the choker/sling is placed determines what will happen as the crane takes a strain. The climber must understand this as it is his butt on the line if he does it wrong.

As a crane operator I would always double check the setting of the choker to be sure that the climber was making his cut so that the cut and choker placement would work in concert to open the cut as a strain was taken. We would often stand up a horizontal limb as it was being cut.

This was done by starting with a pie cut on the top of the limb. Frequently we would employ a tag line tied above the cut to help control the butt end. As the back cut was made the climber would signal when to start lifting. A slow lift was always used to just keep the cut open until a normal hinge was all that was left. Then the crane would lift the piece vertical, just like felling a tree, the hinge would hold the butt until it was vertical. At this point the crane would be directly over the piece, or slightly away from the climber, then the climber would cut the hinge if it had not seperated. The crane should never be used to break the hinge.

Even the ripped piece, clearly visable in the photos, should not have happened. The climber should have finished the cut so the crane only had to lift the piece and not have to break it free. Whenever that happens it will cause the piece of wood to swing, or jump. Neither is healthy for the climber. My goal as a crane operator was to have the piece cut free and just hover over the place it was cut from or move slightly away from the climber. If I had to rotate the piece over the climber I would wait until the climber had moved to a safe location that kept him out from under the piece.

Safety was always our prime directive during craning operations.

As for the type of chokers used. We prefered cable chokers that allowed us to pass one eye thru the other forming a loop. We did not rely on the type of chokers used on skidders that have a sliding hook. We did not feel that these were safe enough to use with a crane. We inspected them after each job and removed from service any that were suspect.

5th November 2007, 02:59 PM	#56 (permalink)
redstree Sappling Join Date: Oct 2007 Location: USA Posts: 23	Re: Are YOU teaching bad habits? How to stand up a limb Trying to get back on track. As someone who has both been the climber working with a crane and the crane operator working with a climber all I can say is communication between the crane operator and the climber is extremely important. Having a crane operator who is familiar with tree removals is also important. We were lucky to have our own crane, granted it wasn't the largest, just 85'(25m) and 5 tons(4.5 metric tons) but it did an awful lot of work during it's life time. When we needed a larger crane we rented one, with an operator. Fortunately we were lucky to have a few crane operators experienced in tree work in our area. When everything is going according to plan it is just like a beautiful dance with the crane operator and climber each knowing what the other is going to do and anticipating the others moves. This sort of dance starts on the ground before the job starts with a discussion about the order in which things will be done. As has been pointed out before, how the choker/sling is placed determines what will happen as the crane takes a strain. The climber must understand this as it is his butt on the line if he does it wrong. As a crane operator I would always double check the setting of the choker to be sure that the climber was making his cut so that the cut and choker placement would work in concert to open the cut as a strain was taken. We would often stand up a horizontal limb as it was being cut. This was done by starting with a pie cut on the top of the limb. Frequently we would employ a tag line tied above the cut to help control the butt end. As the back cut was made the climber would signal when to start lifting. A slow lift was always used to just keep the cut open until a normal hinge was all that was left. Then the crane would lift the piece vertical, just like felling a tree, the hinge would hold the butt until it was vertical. At this point the crane would be directly over the piece, or slightly away from the climber, then the climber would cut the hinge if it had not seperated. The crane should never be used to break the hinge. Even the ripped piece, clearly visable in the photos, should not have happened. The climber should have finished the cut so the crane only had to lift the piece and not have to break it free. Whenever that happens it will cause the piece of wood to swing, or jump. Neither is healthy for the climber. My goal as a crane operator was to have the piece cut free and just hover over the place it was cut from or move slightly away from the climber. If I had to rotate the piece over the climber I would wait until the climber had moved to a safe location that kept him out from under the piece. Safety was always our prime directive during craning operations. As for the type of chokers used. We prefered cable chokers that allowed us to pass one eye thru the other forming a loop. We did not rely on the type of chokers used on skidders that have a sliding hook. We did not feel that these were safe enough to use with a crane. We inspected them after each job and removed from service any that were suspect. __________________ Drive a MINI, the most fun you can have with your trousers on.