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Dan - what did you calculate the tree needed in force to be brought back like that? Then, how did you calculate how much force the truck was pulling with? How many times have you stressed the pull rope to near failure before this one? Which leads to, how much force was on that rope?
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For clarity,
the truck did not do the pulling.. there were two control lines AKA guy lines, AKA right angle lines.. The first line is double braid with 10,000 lb tensile, run through a block and tied off to the pick up. that was pretensioned by the driver listening to my command. I watched the tree, got as much lift as wanted and told him to stop. The tree stood up quickly with surprisingly little pull..
The true blue was set up with a 6:1 MA system and tensioned by hand with 4 men pulling on the line. Max force on the tree estimated at about 2,000 lbs. Max force on the rope estimated at about 1000 lbs. If you listen carefully in the video, you can see that when the true blue was tensioned by hand, it caused the line that had been pretensioned with the truck to go slack, showing that there was significantly less than the estimated 2000 lbs on the line tensioned with the pick up. The pick up was then pulled up again by verbal command until the tree just started to move slightly. Leaving an estimated max of 2000 lbs on that line. The truck was then used as a ground anchor.. it did not move ....
What wasn't shown on the video was how much the tree was stood up.. might have moved 8-10'... At that point I knew there was no change of losing the tree to the side-weight. If it had gone differently, I might have closed the road temporarily..
The tree was then fairly well balanced, and only needed a little persuasion to get it going to the lay. That pull was done with a skid loader, which was off camera.