hairline cracks in primer in corners
nomorecoffee
| Posted in General Discussion on
I’m applying benjamin moore high build primer to freshly installed drywall. The corners are finished with no-coat so there’s no compound in the very center of the corner. I cut in the corners with a paint brush and let it to dry for the night. When I checked the next morning, all the 90 degree and sharper corners had a hairline crack running down the middle. The off-angle 135 corner is mostly intact. All the compound is dry and the space is indoor air. What causes this and how do I prevent it in the future?
Replies
Best I can tell, the paint cracks because it dries on the surface but is still wet underneath because the moisture has nowhere to go with the plastic corner of the bead in the way behind it. I'm getting past this by putting minimal paint in the corners, almost dry-brushing them. I still get a few cracks but much fewer and dry-brush those to get rid of them.
Getting any answers about this has been difficult. No one has seen this before somehow. I find that hard to believe.
Hey there, I'm not too familiar with the "no coat" products because we uze blueboard and veneer plaster in my area. The only thing I can think of is the primer "reacting " with the polymer/rubbery corner material. Is the BM primer water or solvent based?
The primer is the latex-based ultra spec 580. No-coat is basically a fancy paper-faced corner bead. There's plastic underneath but what should be paper on top. It should not be reacting.
Is it something you can include a picture of? Is it definitely the primer cracking/separating as opposed to the joint compound losing it's bond with the no coat?
I can't include a picture because I fixed it all. If it happens again, I'll take a picture.
It's not joint compound losing bond with the no-coat because there's no compound in the corner. You leave the center of the bead bare by design.