How would I smooth out an interior concrete beam?

Question

I live in a building that was constructed in cast concrete. In a few places, the finished wall surface is the raw structural concrete rather than a normal wall construction. (The original interior walls were lath and plaster, and the newer ones are plaster board with veneer plaster.)

They're not obviously unfinished concrete and look pretty good, but there are a few places that irritate me because you can see the imperfections in raking light at certain times of day or when certain lamps are on.

What would be a reasonable way to clean this up?

I'm hoping that I won't need to get into mixing my own concrete, getting a diamond polishing wheel, etc. But I'm also trying to avoid wasting my time with DryDex and basic sanding supplies if that's not actually going to help.

Answer 1

You're going to have to sand down those bumps or scrape them down with a chisel. Then fill in any dents, depressions and really smooth areas with joint compound. After the joint compound dries a bit, dab it with a sponge or short nap paint roller to add the orange peel texture that already exists on the beam. Prime and paint.