This car has done a lot of highway driving over the past year and received a few scratches and dings on the lower front bumper fascia along the way. Last week while coming up I81, I drove through a highway maintenance area and the rocks and gravel did a number on the bottom and sides of the lower bumper fascia.
It looked awful, so I decided to fix it by sanding it down an applying four layers of paintable rubberized undercoat from Duplicolor. This is their premium stuff and will withstand a lot of rock punishment.
Sand out and feather the bad spots and scuff the clean areas and then (as an old mentor used to say) "... practice the fine art of taping shYt up!"
After a day of curing in the garage, I used three heavy coats of GM Gun Metal gray from Duplicolor color the undercoat. After the job was done, I pulled the tape and let it cure in 94 degree heat for a day. Tough as nails -- It wont scratch with a fingernail, bit is somewhat pliable to resist the chips.
This stuff is easy to work with. If it ever needs a recoat, it can be sanded easily and refinished in just a few steps. Good product!!!