"Bill" wrote in message
...
Puckdropper wrote:

One thing you can try that should be simple and easy is to clamp a 2x on
the stretcher at the proposed distance. Push down on the very end and
see how hard it is to make the bench structure move. You basically have
a lever at that point, although not as simple as described in the
textbooks. *g*

Yes Puck, I have been thinking about the vertical (downward) vector that
needs to be supported. And, that the distance from the leg (fulcrum) of
the origin of that vector relates directly to the force exerted on the leg
by that vector. So if someone sets something heavy right on the edge, I
wouldn't want the table to break or cartwheel.

So at this point, we have 5" of distance past the fulcrum. I'm curious to
do the experiment you suggested and see what it takes to lift the back
legs off of the ground, or perhaps, break 5" off of the apron (s). Wagers?


Everyone knows it is easier to push over a longer pole than a shorter
pole. I would expect excessive horizontal force to result in the
screws/wood breaking loose. Intuitively, I think my pole analogy should
apply to the bench, but you have to accept that the force is being applied
at the feet (due to friction?) to make it work. I think this is correct.
I don't claim to be knowledgable about physics. I am just trying to apply
the basic leverage relation.

Again, you are over thinking this. The purpose of a bench is to USE it.
For a lot of different things. And you will be applying force in many more
different ways then the lever experiment you propose. That is why I am such
a proponent of the heavy bench. They don't move around much. And when you
are drilling, sometimes, the force will be in different directions. And
when you use power tools, that adds an even different kind of dynamic.

I remember, years ago, a small time gym equipment manufacturer. He wanted
to emphasize how strong his equipment was. So he hired a guy who had
trained elephants to stand on his equipment. 40 years ago, I was making
coffee tables. I photographed them with a pickup on top of them. That is
my reference point. If they will support elephants and pickup trucks they
are strong enough. Anything less than that is suspect.