Block looks nice, I know what it takes to get to that point, alot sitting with a grinder in hand. I like to put on head phones and get it to it all day, for days. I build Aluminum investment molds & plastic injection molds long before we had CNC's. lots of grinding.
I ground smooth all the welds on our '27 T frame with IRS, IFS.

I understand what you mean by to many rpm's. I like to use the foot controller on the 1/4" grinders(I'm usually sitting), and I like the controler on the grinder on the 1/8' ones(I'm all over the place, free to move).

Pat