i would like to build a machine for polishing stainless steel plate/sheet

i have used a surface grinder in the past on mild steel and if you got your feeds/speeds right you can get an amazing finish , not quite mirror , but with a little bit of work your there

so now stainless

its not magnetic , so would need either a vacuum table with adjustable stops , and/or a vice (which will only work on the thicker stuff

working size is around 300mm x 600mm and dont polish over 25mm thick plate , but i guess 150-200 on the z would be great for clearance

do i build or do i buy a surface grinder ?

obviously it would need to be a mechanical S/grinder as a cnc one would be way outta price ... but if i build then cnc would be quite easy

idea thought's ? and maybe someone who has built a cnc grinder :D