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Just determine compression and tension when the crane as load applied. Cut compression first, maybe pop in a wedge. Doesn't really matter if the cuts bypass at the bottom.
Tony
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On that note of compression side and tension side during fat spar crane picks.
Let's use a clock face viewed from above. Crane's on the 12 o'clock side. Single choker's on the 6 o'clock side, making 12 o'clock the compression side. Now this is a fatty spar with a 4 foot diameter, and my bar's only 28 inches long.
I start cutting on the compression side first with my back towards the crane with my bar's tip reaching the 9 o'clock point on the spar. Then move clockwise cutting around the spar past 12 o'clock to 3 o'clock, to 6 o'clock. Now I'm facing the crane and 9 o'clock is my release point. All with one fluid cut working my way clockwise around the spar, no pinching, no guessing, no danger of the spar splitting, no danger of my bar getting caught in a snap cut overlap. Plus I'm facing all the action when the pick releases and moves away from me towards the crane.
This technique has never failed me and is pretty much foolproof provided your bar and chain is in good shape and cutting straight.
Just my two cents on smoothly cutting fat spars being picked by a crane guys.
Nice vid Bixler.
jomoco
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Thanks Jomoco...
sounds textbook to me. The only thing I might do differently is move around the spar counter clockwise, just to have the powerhead facing downward.
Notice the position of the climber/crane/shackle on the first few picks... the crane sitting at 12 o'clock, shackle at 12 o'clock, and climber also at 12 o'clock. The limb weight of the picks were also generally towards 12 o'clock. Not textbook.
I like to also let the crane op know where the shackle is located. Facing the crane when the pick releases is so important.