Spec Spot Repair III
Once the sanding process is complete, wipe area thoroughly with a prep solvent to remove, degrease and leave surface free of any contaminates. At this stage it is very easy to inspect the rust spot for any pitting which must be addressed prior to moving forward with our process. Unfortunately in this case tiny pits were found which lead us to a grinding process that eventually blew us right through the fender! A few spots to now get the welder out and re-weld the holes shut.
We proceeded to weld and grind the steel flat as to hide the spot repair with our high build 2K Urethane primer.
As can be seen in the photo, our weld repair came out flawless. Now onto the priming. A good self-etching primer should be used first as to give the 2K high build urethane prime something to bite into. In some cases, a phosphoric acid bath followed by a chromic acid bath will convert the surface by slightly oxidizing it with a thin, layered film. This will prevent rust from coming back.
The high build primer is used to bring up the surface of the steel to the top of the paint. This can be done with a foam roller, acid brush or even an airbrush. In this case we used a simple acid brush.
Read the manufacturer’s instructions for time between coats. In this case 10-15 minutes was used. We proceeded to apply 3 separate coats building up a nice height where we can sand it down to the level of the paint.
After sanding, it is wise to then wipe down the surface once more with a prep-solvent followed by a tack cloth to insure dust particles have been removed from the surface.
Our next installment, we will paint the surface. Keep the blue skies up and Happy Motoring!
Lake Country Mfg.