Remodeling bathroom in 55-year-old house…
Original walls were plaster, now replaced with gypsum board. Around door openings, there is a galvanized steel profile that created a smooth quarter-round transition from the original plaster surfaces to the edges of the jambs. (The new wall surfaces are in the same plane as the originals.) Having stripped the old (lead-based) paint off these profiles, I’m down to bare metal. In some places, aggressive sanding has removed the zinc coating from the steel.
The new paint finish on the drywall will be latex over latex primer. What primer should I use on the steel profiles (under the latex finish coats)? Alkyd/oil? Latex? Something else?