[71CHEVYSHORTBED402]

Great info., thank you. Sounds like a red "scotch-bright" pad is a good final metal prep, before cleaning (i.e., wax & grease remover) and conditioning (i.e., metal prep). Sorry about the confusion in the OP, I wrote "scotch guard"......YIKES!

If I'm reading you guys right, the process is:

1. Wax and grease remover (i.e., metal cleaner). You can use this prior to sanding, priming or painting. In other terms, I could: Sand/scotch pad....then wax grease remover, using a cloth to wipe it off (i.e., no water)....then metal prep & epoxy primer or self-etching primer.

2. If self etching primer: Apply, flash and then apply high build primer (e.g., urethane 2k primer) or paint.

3. If epoxy primer: Metal prep then epoxy primer. If I understand correctly, the epoxy has to dry before the next coat, but if it sits say 24 hours or so, then you need to scuff it up.

4. Phosphoric acid: Never use two chemicals with phosphoric acid, such as metal prep followed by self-etching primer.

5. One last question, (we can only hope). I believe I've read you can leave epoxy primer without a top coat. In other terms, it provides the metal a good barrier from water vapor. If using self-etching primer following by high-build primer, you need to top coat relatively quickly, because it doesn't provide that barrier, or rather, it's a temporary barrier pending paint?????????????????????????