I had a linisher in mind for a while, then when I saw a 3 phase motor lying in pieces at the scrap yard, I thought the rotor and bearings would be ideal, asked about a second motor and they had one so I dismantled it too. second rotor is a bit smaller in dia but same length so I can live with that. I can always make them the same size on the lathe as I will be turning the middle part down to suit the alloy ends which are a bit smaller anyway.