Advertisement For RaceRap Customer News
Steps for A Typical Body Repair and Refinishing
Jul 10, 2011 - updated Jul 10th, 2011 10:27am
Web posted by Bob Barney
Steps for A Typical Body Repair and Refinishing
Detergent Scuff:: Clean area to be refinished using a hot, soapy water mixture. Use a gray nylon scuff pad to agitate the surface and remove all water-based contaminants. Thoroughly scuff to remove all surface gloss and produce an evenly dull surface. A liquid scuffing agent may be used along with the gray scuff pad to increase effectiveness and speed the process. Rinse surface clean with water. Dry work area with a clean cloth and compressed air and continue paint process.
Solvent Clean: Thoroughly clean the surface to be refinished with HR-397 Pre-Clean wax and grease remover to remove all solvent based contaminants. Apply to all areas to be painted, one panel at a time. Wipe off with a second clean, dry cloth before the area is allowed to dry. If drying occurs, repeat application..
Grinding: If body filler is to be used, the surface must be ground to clean, bare metal using a rotary grinder and a 36 grit grinding disc. Avoid using the edge of the disk. Expose an area just slightly larger than the body filler will be applied to. Blow off the area that was ground, and surrounding areas, with compressed air.
Rough Featheredging: Sand all broken paint edges using the DA sander and 80 grit sandpaper. Hold the DA flat against the surface and avoid using the edge of the pad. Continue sanding until the broken paint edge becomes a smooth transition between the metal substrate and the old finish.
Apply Body Filler: Mix body filler according to label directions. Immediately apply in thin even coats following the contour of the original panel.
Rough Sand Body Filler: Sand body filler with 80 grit sandpaper and a hard sanding block. This rough sanding is done to “shape” the body filler to match the contour of the surrounding metal. If more filler material is needed, blow off area with compressed air and re-apply body filler. Finish rough sanding with 180 grit sandpaper to remove all 80 grit scratches.
Finish / Featheredging: Inspect body filler for the proper contour, 80 grit scratches, or pinholes. If defects are found, re-apply body filler. Featheredge all broken paint edges or scratches in surrounding paint using 180 grit sandpaper and finish with 320 grit sandpaper on a DA sander. Blow off the repair area, and surrounding areas, with compressed air.
Apply Primer Surfacer: Apply either HP-8000 or HP-5310 Primer Surfacer. HP-8000 IS NOT a direct to Metal Primer, so if you have plenty of bare metal use only HP-5310 or HP-5311 (Black and also Direct to Rust). Apply 2-3 medium coats allowing each to flash to a dull finish. Allow to dry a minimum of 2-4 hours.
Guide Coating: Guide coating is done to help highlight areas that require additional sanding during the Block Sanding Step . Apply a thin dusting of guide coat over the entire primed area. Allow to dry for a minimum of 10 minutes.
Block Sanding: Block sanding is done to perfectly level the repair area and provide a smooth transition between the repair area and the old finish. Begin by sanding the repair area with 240 grit sandpaper and a hard sanding block. Sand only enough to remove the guide coat. Do not over-sand. Re-sand the area with 320 grit sandpaper, followed with 400 grit sandpaper. If repair area is not to be sealed, final sand with 600 grit sandpaper. Blow off the repair area, and surrounding areas, with compressed air.
Sealing (optional): Not really recommended when using Tamco Primers, but this optional step may be chosen to fill small scratches or increase adhesion of the new paint over the old finish that havsn't been primed. Use either Tamco Hp 3500 series sealer or HP-5310 as a sealer (see mixing instructions). Apply 1-2 medium coats. Allow to flash hand slick between coats. Allow to dry until hand slick (usually about 15-30 minutes depending on temperatures and film thickness).
Apply Basecoat: This is the actual color coat to match the vehicle’s original finish. Apply 2-3 medium wet coats. Allow to flash handslick between coats. Basecoat will dry to a dull or satin finish.
Apply Clearcoat: The clearcoat is the protective layer that gives the BC/CC system its gloss and durability. Mix according to the selected Schramlack Clearcoat label directions. Apply 2 medium wet coats. Allow each coat to flash until hand slick before next coat. Allow to dry overnight.
Buffing / Polishing (optional): During the application of the topcoat system surface imperfections may occur because of airborne dust or other environmental factors. To remove these minor surface imperfections, allow the clearcoat to dry at least 24 hours. Lightly wet sand with 1200-1500 grit sandpaper. Polish the surface with a good grade buffing compound to remove the scratches from the sandpaper. Finish the process with a machine glaze and a clean pad.