I have been looking into getting my chrome bumpers -> black ..
My local powdercoater won't do it 'cuz he says they need to be sandblasted to get all the chrome off,
and he can't guarantee the results,,
but I found this (stolen from (ahem F150 forum) http://www.***************/forums/ar...nt-chrome.html
Here is a step by step tired and tested method for painting chrome.
1. Clean Chrome
surface with brake
clean to remove the grime (break clean will not leave any residue).
2. Wipe off any left over brake clean and blow any areas that could hold brake clean with air.
3. Follow this by an ammonia base window cleaner
4. Next mask off any areas that will not be paint as the next step involves abrasives.
5. Using a red scotch brite pad scuff all surfaces to be painted. You can use sandpaper if you like just keep it fine 120 grit and up. You dont want to sand through the chrome just scuff it up.
6. Now use a reducer to draw out any containments that have been pushed into the scratches while sanding. Make sure the surfaces to be painted is very clean as paint will not stick if not.
7. Re-mask areas that are not to be painted. Use green painters tape as it is thinner and will look much better.
8. Now the hardest part about painting chrome is adhesion. The best stuff on the market for this is House of Kolor APO-1 Adhesion Promoter
. Now make sure to lay this stuff down thin as if you put to much on it will act as a delaminator. Good rule of thumb is a nice medium wet coat. Let dry for 10 minutes before laying down next part.
9. Next use PPG
DP90 Sealer which is a non-etching sealer the reason for this is because an etching sealer will work against the Adhesion Promoter. Lay down a single coat of the sealer. Again you dont want alot of build up. Let dry for about 30 minutes.
10. Next lay down a single coat of your base. Let dry for 20 minutes.
11. Finally lay down two coats of clear.
12. Now enjoy those newly painted parts
for many years to come.