I have a Kanemasa suji that is pretty beat up with scratches, ugly patina (tried to force it before I knew what I was doing then gave up and just used it) and now it's got some surface rust. Barkeepers Friend isn't really touching the patina at this point, so I think I need to go with something more abrasive. What do you guys recommend just to give me a smooth, clean blade that I can start over on? I'm not looking for a mirror finish or even factory perfect, I'd just like to clean it up to good enough and start over.
I don't really have any equipment other than a bench grinder and don't really feel like investing any money into equipment. I'm thinking maybe 600 grit sandpaper might do the trick, but I'm not sure if there are any brands/types I should look for or avoid.
Thanks for any help you can provide this newbie.