Posted by Joe Baker on February 24, 2003 at 10:14:43:
In Reply to: A question of physics posted by Sven Bring on February 24, 2003 at 09:50:10:
The thing that would change (slightly) is the undesirable torque that would apply to the valve about a horizontal axis, wherein the stop arm would be pushed from the hand, while the bottom bearing would be pushed toward the hand. By moving the attachment closer to the top bearing (pivot point) you would shorten the lever arm, thereby decreasing that torque.
The way to virtually eliminate unwanted forces would be to devise a mechanism that pushes one side of the valve while pulling the other, and does so on the top and the bottom, with equal force. I suspect such a mechanism has been tried by someone somewhere sometime, but it seems prohibitively expensive and inherently less reliable.
Joe Baker, who suspects that proper lubrication is a better solution.