Many thanks, Stewie!
Before I read your post I had already gone and bought a "Diamond cup grinding wheel" (http://www.dta-aus.com.au/products/RGD100TC).
Seem to be making a dent. But you…

Hi,
Apologies if this is sort of off topic as I am neither a builder or a renovator. I am a scientist seeking practical advice on how to polish a steel…