Free 173 Best Homemade Tools eBook:  
Remove advertisements
Results 1 to 4 of 4

Thread: Uprooting a tree using a 45:1 pulley system - video

  1. #1
    Content Editor Altair's Avatar
    Join Date
    Aug 2013
    Thanked 947 Times in 281 Posts

  2. The Following 6 Users Say Thank You to Altair For This Useful Post:

    baja (02-24-2019), Frank S (02-22-2019), KustomsbyKent (02-26-2019), oldpastit (02-24-2019), Scotsman Hosie (02-23-2019), Seedtick (02-22-2019)

  3. #2
    Radioman's Avatar
    Join Date
    Jun 2018
    Thanked 47 Times in 30 Posts

    Radioman's Tools
    Remembering my high school physics class I believe you add your compound systems not multiply. I think your system is about 10 or 11 to 1 and not 45 to 1. What was your input pull? Let’s just guess 100lbs. In a 10-1 system you’d be pulling at about 1000lbs and not 4500lbs as first stated judging by the way the tree came out of the ground my guess is you were pulling at the lower number? IMHO. it’s been a long time since high school physics class.

  4. #3
    Masterjuggler's Avatar
    Join Date
    Mar 2017
    Thanked 9 Times in 7 Posts
    I'm fairly certain it's a 35:1 system, assuming he actually has a 5:1 at the end. Let's say he pulls with 1lb, that's 5lb out the purple pulley. The line out the purple pulley terminates at the tree, still tensioned at 5lb. That line also runs through that middle pulley, causing the line out to be 10lb. That runs through a red pulley at the tree pulling the tree with 20lb. That runs back and terminates at the tree again, with 10lb of tension.

    So just the tension at the tree: 5+10+20=35lb from 1lb initial force.

    I tried drawing up a diagram, but a nice way to represent it in 2d eludes me lol.

  5. #4

    Join Date
    Mar 2017
    Thanked 45 Times in 29 Posts
    Kinda reinforces the perception of the power of the wind in a blow down.

    Post your reply!
    Join 33,912 of us and get our 173 Must Read Homemade Tools eBook free.

    173 Must Read Homemade Tools

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts