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Hi there,

I've just built a crane (well, actually a jib arm), to be used on a film dolly with
a camera on one end and a counterweight on the other to balance it.
I'm a bit worried about the weight I'm putting on the bearings and so I started
calculating. But I'm having a bit of trouble figuring out how much weight is
being put on each point. How much weight is PIVOT POINT A taking and how
much weight is PIVOT POINT B taking? Could someone enlighten me?
The MAIN ARM has a mass of 2.1 kg/m and the CONTROL ARM has a mass of
1.1 kg/m. Then there is the mass of the camera on one end and a massive
counterweight on the other end. Does PIVOT POINT B actually take any weight?

Thanks very much for any help.