Posted by John Swensen on May 10, 2002 at 14:36:00:
In Reply to: Re: Re: Re: Re: Re: Re: Re: Short action posted by Rick Denney on May 10, 2002 at 12:53:27:
Rick,
While I agree with your conclusion, I must, respectfully, disagree with the statement that pushing from an offset point creates no lateral force. The inertia of the piston and an offset push will produce a turning moment, which will result in side forces (against the casing in the direction of the offset at the top of the piston, and in the opposite direction at the bottom of the piston). Put another way, if the direction of the applied force does not pass through the center of mass of an object, the object will be subject to a turning moment. More intuitively, imagine pushing (gently) on a floating object in a bathtub; if you push on the object off center, it will rotate, as well as move away from your finger.
Nevertheless, I do agree with Rick on the relative magnitude of side forces; I, also, would prefer an offset button (and the trivially-small lateral forces it causes) to a stretch and the often-substantial lateral forces caused by not pushing straight down.