[JoelP]

Originally Posted by Not2B

Don't worry about the weight. It has no effect on the coefficient of friction. It DOES, however, effect the force from friction. Force of friction = Coef of Friction * Normal Force. The weight is what we would call the "Normal" Force. At least, it is on a flat surface. (The normal force is really perpendicular to the surface you are thinking about, so a robot on a ramp has a force down based on weight, and a portion of that weight as a normal force.)

I just looked that over - if I confussed anyone... I'm sorry. I should look for a picture to explain that.

But I think your question has been answered. If you want to test the coef of friction of materials, let us know - I know there are several simple test rigs you could use. (But be careful... there is Static Friction, Dynamic Friction, Rolling Friction, and others, etc... make sure you learn the difference and check for the right one.)

I was only worried about that because the larger weight limit would create a larger normal force with the same coeff. of friction which would result in a larger frictional force than I had designed the transmission for.