Tutorials

A rust hole doesn't take body filler. It takes fiberglass: polyester resin, and a mat or a cloth laid over the hole. Here's the whole lay-up from the makers' own data sheets (USC, Bondo, Evercoat): which one bridges the hole, the 2-inch margin, how many drops of hardener per ounce, how long you have once they're in, the wet-out, the dip for the next coat, and sanding, skimming and priming the cured patch.

How far back do you hold a spray can, how many coats, and how long do you wait between them? Every one of those numbers is printed on the maker's own technical data sheet — and they are not the same from can to can. This video reads them off the sheets for SEM, U-POL, High Teck and SprayMax aerosols: distance, coats, overlap, flash time, the window to the next product, and the temperature it all assumes.

1K or 2K clear coat? The number on the can says whether there's a hardener inside, and the makers' own data sheets say where each one belongs, how many passes, how long to flash, and how long a 2K can stays good once you press the button.

Body filler, glaze and fiberglass filler each do a different job in a dent or rust repair. Here's which one goes where, how much hardener to mix in, and the five mistakes that make a repair show through the paint.