Preparing for Base & Clear Coating
Posted by Jay Schneider. Filed under Automotive.
September 8, 2010
Once the primer has cured, sanding may be necessary to level the finish. If this is the case, you may want to knock the primer down with 220 to the point where enough primer is left on the finish to sand with 320 or 400. 220 grit is too aggressive and will bleed through thus revealing the marks in the clear coat. Follow the rules by sanding in the proper direction, that is straight-line sanding on flat surfaces and in a bias direction when on a compound curve.
Once your high build primed surface sanding has been sanded to the proper finish, it is time either seal or base & clear coat the finish – check with the primer manufacturer for the their suggested procedure. If sealing, apply per Manufacturers’ Data Sheet and proceed to base & clear coating. If base / clear coating, determine the most outer portion of disturbed area where your repair has been done, and wet sand with 1000 to 1200 grit paper about 2.5” to 3.0” inches out from the edge of your repair. This sanded area will be used to “melt in” and flow out the area where the wet paint meets the dry paint rendering the repaired area unnoticeable.
Wipe the repaired area down with a solvent specifically used for cleaning that will not dissolve the coating on the surface – i.e. DuPont Final Clean. Use a tack cloth to remove the dust particles. Proceed to base the repaired area following the manufactures recommended procedures. Apply to base coat out to and half way over the area previously wet sanded with 1000 or 1200 grit sandpaper. Allow the base coat to
completely flash off prior to wiping the surface with a tack cloth. I like doing so in-between base coats – this helps to assure a dust free surface. Once the base coat has dried per manufacturers instructions, it is time to clear coat the finish. This will be our next discussion in Rust Repair.
Scott S. Mc Lain
Lake Country Mfg.