I was going to say that i`ve worked in various types of engineering for 30+ years and never used valve grinding paste . well only on engine valves
servicing diesel injectors years back , you used to strip them down and put the components into a mini spinning jig and then apply really really fine green coloured abrasive paste to clean them up . It was so fine you didn't need gloves ....H& E will prevent you doing that now . Injectors are probably just scrapped now i shouldn't wonder .
