Write a step-by-step procedure sheet for preparing a plastic area (with adhesion promoter) for refinishing.

Question

What will be an ideal response?

Answer 1

The preparation of a repaired plastic part is more complicated due to the potentially different levels of the surface, which will need to be made level through using
primer-filler and blocking. The steps are as follows:
Clean. The repaired part is first soap and water washed as described earlier, then cleaned with a nonstatic plastic cleaner.
Feather Edging. The repaired area is feathered with a dual action sander (DA) using P240 grit paper.
Sanding. The area to be primed should be sanded using P320 grit paper.
Reclining. Following the sanding, the parts should be re-cleaned with nonstatic plastic cleaner, and then tacked.
Adhesion Promoter. Apply adhesion promoter if required.
Priming. The recommended plastic primer filler should be applied according to the paint maker's recommendations, which may call for a flex additive.
Blocking. Following the paint maker's recommended flash and cure time, the technician should block the primer with a hand block, using P240 grit paper. A guide coat will help the technician identify high and low spots, indicating when the surfaces of the repair area
are no longer visible. Then the part should again be cleaned with nonstatic cleaner.
Sanding/Scuffing. The primed area should then be sanded with P320 grit paper, followed by sanding the entire part with P400 to P500 grit paper. The next step is scuffing the part's surface with an ultra-fine scuffing pad. The area to be finished should be deglazed and have a uniformly dull area.
Final Cleaning. Final-clean the area to be refinished with a nonstatic plastic cleaner. Then tack for topcoat.