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Calc line length block & tackle

Calc line length block & tackle

Calc line length block & tackle

(OP)
Where can I find a formula or calculator that will calculate the length of line needed for a 6:1 block & tackle system?  For example, a 70-foot tower is lying prone and needs to be raised to the vertical.  The tower pick-point is at 50-feet, the vertical pick point is at 45-feet.  If, Line-1 = 67-feet, what overall length of line is required across the entire pull?  *Assume line stretch = 0 and Line-6 terminates at the sheave block.  Thanks ahead for the help.

Tomcad

RE: Calc line length block & tackle

Found this on during a search for 'block and tackle'

http://iws.ccccd.edu/jtsizemore/OCsubsite/Physics172/LAB43Pulleys.pdf

Is the attached sketch what you've got?

Think it's just a matter of laying it out for your 6:1 ratio (ignoring the initial 45' portion), count the strands
for that ratio, multiply x 67', and then add the 45' plus whatever additional length you may need at the ground.

 

RE: Calc line length block & tackle

...scroll down to IMA paragraph

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