When sanding a defined flaw,...
When sanding a defined flaw, be wary not to over-sand. Let the filler feather well into the adjacent areas.
Three even coats of MP75 were applied, allowing the solvents to flash between coats. The smoother the primer is applied, the more effective it will be in leveling the body surface later when it is block sanded, and less work will be required. We used one grade slower reducer in the primer, which improved the surface finish, but slowed the flash time. After the primer was dry, it was sprayed with a fog of black guidecoat, which is an important aid in sanding. We used black basecoat with extreme reduction, fogged on with high pressure to create our guidecoat, although commercial mixes of specialty guidecoat are available. Do not use a spray can enamel as a guidecoat; it is too coarse of a pattern and will tend to clog the sandpaper, especially if dry-sanding. Even in primer our Vette looked great, a big improvement from the patchwork of body filler we had been staring at. Once the primer is applied and cured, the block sanding process begins.
Feel is your friend when trying...
Feel is your friend when trying to make the panels perfect. A good sense of touch will find the flaw you will never see in the dull fiberglass.
A light scratch mark made...
A light scratch mark made to an area that needs attention will help get the filler in the right place. These "X" marks indicate a rippled area in the factory fender.
A significant amount of time...
A significant amount of time went into the filler work, which will translate into less primer thickness later, which leads to a more durable finish in the end.
Overall, the metal birdcage...
Overall, the metal birdcage of our Corvette was in good shape, but there was a small rust area at the windshield pillar that needed to be cut out and replaced with fresh sheetmetal. The repair was butt-welded in place with a MIG welder.
Before the primer application,...
Before the primer application, the entire body was given a final light detail sanding with No. 180 grit using a hand pad. This cleans any wayward filler and helps locate any other areas needing work. All of the edges and recesses are detail sanded.
A good dust-down with an air...
A good dust-down with an air nozzle clears the sanding dust and will dislodge debris that could come loose while spraying.