I'll be round tomora or tues for it cheers Craig, i'll be in touch... just out of interest where'd you get em from round here, sutcliffes/barnes?? Is it just basically a diamond bit that fits on a grinder, do they not burn out for fun at such a high speed on porcelain??
Slowest drill speed Andy and keep it wet. Don't run it on high speed it will screw the core bit up with the heat