Fix Steel Imperfections
We are currently doing a ground up car dealership (new). Our scope of work is typical for any commercial job. We are doing walls, lots of dryfall (ceilings) epoxy and a bit of wallpaper. What was not in our scope of work was to fix steel imperfections on door jambs.
On many commercial jobs the general contractor will whip out the awful bondo that is typically used to repair imperfections on cars. This product would work as a first coat if they ever had anybody that knew anything about how to apply it. We were on a large apartment complex job a couple years ago and it was a mess. Every time we turned around there would be someone slathering bondo on metals doors and frames.
On this job the contractor asked us to take over and fix steel imperfections on the jambs of the overhead doors that lead into the garage areas of the dealership. This was of course after someone else gave it a go. Yuk
Most of the imperfections were simply where the jambs were screwed into the wall studs.
Bondo is not easy to sand and if you have a large amount of it and it is not smoothed out it while wet it becomes a pain to sand down smooth.
The approach was to use an orbital sander with 80 grit paper on it to bring it down smooth and then use a detail sander to smooth the edges out. Then we used MH to skim over that repaired area to make it super smooth. MH is a great exterior spackle product. It dries very hard but is not terrible to sand.
These door jambs were made from galvanized steel so we also needed to clean them. Often they have a mill oil on them from when they are made. That oil must be removed prior to painting. We also sanded the entire jamb down to knock off burrs, etc.
Next we primed all those smoothed out areas and used Amershield as a top coat.