Do you have access to the motor? If so, you can measure the phase resistance with an Ohm-meter. This measurement goes a long way in estimating the copper in the phase windings. In particular, with this measurement, you restrict the wire-gauge/wire length combinations that are possible. One can then estimate the wire gauge from the current level, which is estimated from the known power and voltage. Once you know wire gauge and wire length per phase, estimating the amount of copper is easy since the conductivity of copper is known. It is also helpful to provide some details of the motor type and dimensions of the motor, rotor and coils, since estimates of coil volume also help refine the estimate of copper weight, since the density of copper is known.Would anyone care to guess ( or if you know) about how much copper would be in a 350 horse power, 3 phase, 3100 pound motor? Even a ruff guess would be better then i have now. Thanks in advance.