Not to forget that a soft metal will have some flex to it. It can also be weaker where the inserts are for the coils. Is the point to try and make a low voltage machine? Because No Iron makes a good point, it could run too fast. You may need a larger capacitor an run it at lower voltage. Then you have maybe a quieter machine that runs fast at low voltage. It is a lot of work. I am curious about what you are trying to do.