As far as that site is concerned, I linked to their metals section and it describes cold roll steel, hot roll steel, aluminum, etc. and all various thicknesses. Clearly aluminum would be lighter weight, yes. Let us know what you dream up!   Also, I just sized some urethane round belting for the new motor since I had to find the exact size of a new belt to get it to fit, I figured I’d check this stuff out. There are videos explaining how to melt the urethane to make a belt, in case you’