DaveEdin Run a drill with a wire wool bit over them to take the majority off first then paint, I'd guess...
Jim (jimxms) did this recently and went from red to silver, there's a thread around somewhere for it...
Aye, I'd totally recommend getting a cheap set of wire brush drill attachments in various sizes and shapes. I got a set from eBay for about £5.
I also bought some STP Brake Cleaner for cleaning off all the dust and dirt once you've rubbed them down. it works well and dries really quick, so there's no need to wait ages before painting.
My process was a bit like this:
- Cover area of car you are working on with a large blanket. Even though its only paint dust that will be coming off when you rub them down, It doesnt take much imagination to work out what will happen if your car is covered in red paint dust and it rains :p
- Remove the wheels (using the usual precautions)
- Take straight to the calipers with a corded drill and the wire brush attachments. I went all the way back to bare metal when I did mine so I could get a perfect finish. But as long as you've got a 'keyed' surface for the new paint, you can probably get away with not going that far.
- Heavily spray the whole area with the STP brake cleaner. This will make a really big oily/paint puddle on the floor, so if you've got a nice driveway be sure to get plenty of cardboard on the floor.
- Once the brake cleaner has dried <5mins, use masking tape on the brake disk face.
- Use cardboard to enclose the wheel arch area (to prevent the wind from affecting the paint spray direction). Also make sure it covers areas of the wheel arch and suspension that you dont want to get covered in paint.
- Cover as much of your car as possible in sheets to avoid any overspray. Its 10x harder to remove caliper spray paint than it is normal spray paint from your cars paintwork (as I found out).
- Spray light coats on the calipers about 5-10 minutes apart to get a get an even coverage. I used Halfords caliper spray paint - which was really good!
- Leave them to dry for about 3 hours, then take the car for a quick drive around the block (if the weather is ok) to prevent the calipers from gumming up.
- Leave then to try properly for another 10hrs or so before attempting to apply caliper decals.