I did some searching on the forum and it seems some people paint the rotors. I'm about to do a brake service myself and I purchased qty. 4 new AC Delco rotors for my GS. The rotors already seem to have a sort of painted coating so is this still necessary? If so, is this purely for cosmetics and what do people use and how?

 

The AC/delco rotors are carbonized to help slow down the rusting, but will still rust over time.

So using some Acetone to de-grease the rotors first, it's the sections that the brake disc's that are not going to touch the rotors that you want to paint.
Note, need to go back in with an air brush touch up the paint edges that have chipped away over time next time I pull the rims to clean and wax the inner drums.

 

Wow, seems a bit OCD (no offense intended btw). Thanks for posting the info as it's a huge help to me!

I'm curious though if this would really add a significant benefit over how the rotors came from AC Delco. Surely GM doesn't do this when they build Corvettes and I don't see much in the way of rust or corrosion on my 5 year old rotors. I don't foresee much abrasion in these areas either (other than where the pads contact the rotors).

Do many folks actually go through the trouble of painting the rotors? Also, if I do this do I need to first remove whatever AC Delco put on their during manufacturing?

 

The carbonized surfaces of the rotors will accept the paint after the discs are de-greased. So the only prep needed to spray coat the rotors is just to degrease them now before they start to rust. The spray brake cleaner works well if the rotors are not that greasy to begin with, but just easier to stick them in a pan with acetone to leach the grease off the rotors in say the vain areas so the pain can bond to the metal there too (anywhere you don't remove the protective grease before painting the rotors, the paint will not bond to the surface and quickly flake of instead).

Yes, the carbonized finish will start to rust on the quicker side, but since the finish its black, it's just harder to see the rusting to begin with until it builds up to the point that the least of **** person can't live with it any longer.

http://www.acdelcotechconnect.com/pd...CONNECT_R1.pdf

Myself, I have a glass bead blast cabinet, so knocking off the rust on older rusted rotors is a snap to paint the later. If you don't have such, then suggest that you paint them now, instead of waiting when they are rusty instead, and having to first remove the rust the long way by hand, before you paint them later instead.

To add, in the future, if you want the rotors to look good for a long time (since you can see them clearly through the rim spokes), and don't want to have to paint them to begin with, then get plated rotors instead.

 

One lap on the track and all that paint work burns off.