Metal scuffing question

[Charles in SC]

On my -7 qb the folks did a very nice job of scuffing the metal, so nice that I cannot believe they used a scotch brite pad. I think they must have used some sort of power tool like maybe a stainless brush wheel or something. Anyone have any ideas on that?
Thanks in advance.

 

[N674P]

Scotch Brite on a DA (dual action) sander works great for scuffing - I think it's effectively 320 grit. You can be sure they didn't use stainless steel, or you'd be set up for a hellacious disimilar metals corrosion problem.