Sanding Grit Used When Skim Coating Walls?
JoeJoyce
| Posted in General Discussion on
I have a project where I will be repairing horse hair plaster and then skim coating with joint compound (roll the compound on the wall, use drywall tool to skim it off and then sand). I’ve read that I should use 200 or 220 grit sand paper when sanding it done. Frankly I find that even 220 leaves some marks. So I do the final sanding by hand and use 400 grit sandpaper which leaves a nice smooth wall for painting.
Is there any reason why I can’t go higher than 200-220 (meaning, what’s wrong with using 400?) I find articles that say not to use more than those grits, but not why.
Any thoughts?
Thanks, Joe
Replies
Joe,
I use a sanding screen and I think it’s rated 100 on a 4x9 block with a handle (similar to a pole sander except for the “trowel” handle).
Oval sanding pattern. Grit usually means what type of hardness the compound. Anymore, don’t use bucket mud. Durabond (hard) or Easysand (softer). Often I’ll dip in water for a repair in a commercial job.
Rolled on mud and then sand, never did it. Have done a “roll coat” to match what’s there.
I’d think 400 grit would clog immediately.
Try to find a higher number sanding screen. See what happens. Think circular or oval pattern.
If the mud is bone dry I don't think it would clog but I can't imagine you would see any benefit with 400 grit over 220 grit. After all, you are going to put paint on it aren't you?