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Unread 04-11-2013, 20:37
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Re: Counterbalancing elevator's

Quote:
Originally Posted by smart1 View Post
What would be an advantage of slaving the 3rd stage over a continuous cable?
In a continuous cable system you have to pull much more cable to raise the hi-lo to full height. As that cable/rope wraps around the winch the effective diameter of the winch increases. That changes the tension on your rope and can cause issues. The use of flat spectra or very small diameter cable or rope can help that situation. In-line springs can also take up any change in tension.

Slaving the two, however, requires much less rope be wrapped on the winch for a full hoist. We've never had to worry about a spring system in a multistage slaved setup. The stretch in the rope has been enough so that we don't have to worry about a spring loaded tensioner. We just tension it all by hand.