That might be the way to go in S scale since we prefer all metal driving wheels to use with split axle insulation/pickup. I can obtain wax or castable resins so there's no problem in producing masters. The one problem we have found in the past is getting a suitable brass. We carry a small range of generic cast driving wheel centres and the member who set this up some years ago had to try several casters until he found a brass which would machine well. However there is a trade off since the finish quality is not quite as good as can be achieved with other brasses so a wee bit of finishing work is required. Jim.