Blake Ashley wrote:
> Maybe an engineer can tell us how much force
> is developed by a half-inch screw being turned by say 50 pounds at the
> end of a 12 inch lever? 

Lessee. A full turn of the lever moves
the end through 2 pi R inches,
i.e. 75 inches
The screw moves through 1/2" per revolution.
So the mechanical advantage is 75:1/2 or 150:1
A 50 Lb force thus becomes 7500 Lbs!
Even 10Lb becomes 1500 Lbs

    BugBear (who hopes he got that right)
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