Nothing "magical" about it... http://www.howstuffworks.com/pulley.htm has some good graphics although no description of the force on the fixed pulley (our ginpole), so one needs to sum up all the "do
Correct you are! The minute Lightweight Larry begins his fateful upwards journey, the whole equation changes. Any downwards tension beyond his weight disappears in that situation. "And then, while I
The reduction mechanism of a ganged pulley system is in the number of feet of rope the worker pulls in as a ratio to the distance the load travels. In a two to one system the worker pulls 200 feet of
start with this, a single pulley at B with a 300lb load at C and a 300lb person at A holding it off the ground. there is 300lb of tension in the rope to hold the load up, so at B there is 300lb pulli
N4KG comments / questions inserted below. How is this 2:1 mechanical advantage achieved? Scenario 1 - End of rope is attached to the frame of the top pulley. Rope runs down to Second pulley with hook
See other post on how advantage achieved. A gin pole is just a device to give an attachment opportunity high enough above already accomplished structure to allow fixing various lifting devices to con
i have not had a need to do it, but a 2:1 arrangement would also be easy to do. all you need to do is tie one end of the rope to the top of the pole, run through a single moving pulley where you atta
Why is this NOT how a gin pole is configured? Even if one ties the fixed end of the rope to the tower (say when lifting a beam or rotator that need not rise above the tower top), one has not material
Just a point of clarity, a gin pole is also the structure that is used to erect an assembled tower/antenna/pole from a horizontal to a vertical position. See other post on how advantage achieved. A g
I agree completely with your analysis Guy. Which end of the gin pole rope is attached to a "block" ? q.e.d. Bottom Line: The mechanical advantage in a lossless system equals the number of supporting
Three to one or ten to one advantage via pulley systems all acrue to the puller. Gravity still says to lift up 300 pound up the effect at the pull to point will still be 300 pounds regardless of effo
In that case the already accomplished structure is the base structure, which could be just a hole in the ground, or a ring bracket on the deck of a ship. List Sponsor: Are you thinking about install
More N4KG observations and comments inserted below. The distance traveled is a RESULT of the mechanical advantage, NOT the CAUSE, but can be used to calculate the mechanical advantage. N4KG Note the
Hello, So the weight exhibited to the Gin pole at the top pulley mount point is the down force of the load line plus down force it takes to hold the load static at the workers end of the load line? N
wrong... as i pointed out it is possible to get an advantage for both the puller and the pole by the use of a single top pulley and a single travelling pulley. that is the basic 2:1 system where you
Yes, right. But this is not, apparently, what N4KG is saying... The kicker is, in your words, "plus down force it takes to hold the load static at the workers end of the load line". In a system with
Hot damn! Someone finally 'splained this so that some of us non-gradgiated folk kin unnerstand it! I knew what was being said was true, but when I tried to put the argument on paper, I couldn't make
Author: James.E.Brown@lrdor.usace.army.mil (Brown, James E LRDOR)
Date: Wed, 13 Jun 2001 11:50:37 -0700
And what if there are no workers applying "downforce", but instead the end of the line is tied off to a tree, and the load is suspended static? Jim W4LC Hello, So the weight exhibited to the Gin pole
Author: w7ni@easystreet.com (Stan or Patricia Griffiths)
Date: Wed, 13 Jun 2001 11:39:03 -0700
NO, NO, NO . . . DON'T THINK ABOUT IT. MEASURE IT YOURSELF AND YOU WILL SEE THAT JIM IS EXACTLY RIGHT. If you think I am shouting, you're right. Being polite and subtle doesn't seem to work . . . Obv
Author: w7ni@easystreet.com (Stan or Patricia Griffiths)
Date: Wed, 13 Jun 2001 11:48:12 -0700
Another non-believer who obviously has not tried the experiment and made the measurements. Stan w7ni@easystreet.com List Sponsor: Are you thinking about installing a tower this summer? Call us for in