Thread: Grappling hook?
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Unread 14-01-2010, 01:51
elmer_fud elmer_fud is offline
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Re: Grappling hook?

Quote:
Originally Posted by viperred396 View Post
I remember reading somewhere that after hanging a large weight from one of those ropes you shouldn't use them again because they might break. even if it hold during testing and the practice matches but then it might break in the qualifiers causing you to lost
I think climbing rope will be overkill. A climbing rope will require something over 1000 pounds to break. Some parachute cord (1/8 in rope) has a breaking strength of 300 lbs but you would likely break this using it with a 150 lb robot. I think something in the area of 3/8 inch rope would work well

With climbing rope you are not supposed to use it again after a hard fall ( several feet) because it is weakened. Putting 150 lbs on it repeatedly will not hurt the rope.

references
parachute cord http://www.rei.com/product/784296

climbing rope http://www.backcountry.com/outdoorge.../EDL0009M.html (9kn is about 2000 lbf)