I am wanting to make a tumbler to wash my brass. I have an electric motor from a washing machine and I need to figure the pulley sizes needed to get to the proper RPM. The RPM of the motor is 1725, the current pulley on the shaft is 3/4 ". Can I get to 35-45 RPMs with a second pulley and if so, what size diameter does it need to be? For all you geniuses help me out.