# Repairing drywall seam after mesh showing hairline crack



## Genec (Jul 18, 2009)

I just completed a paint job after a repair was done to our ceiling. A skylight was removed, new sheetrock put in but they joined the wallboard with mesh tape. Even after going over it with Easy Sand 90, primer and BM paint (Waterborne ceiling paint), a hairline crack is showing where the mesh joined the wallboard.

My question: I have peeled the paint off the repair. Should I remove the mesh or put paper tape on top of it or does it matter?


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## DUDE! (May 3, 2008)

You shouldn't of been able to peel the paint off, maybe the compound wasn't totally dry. If you still are seeing the tape, apply more compound and feather it out.

reread your post, could be a small problem, someone else did the patch, you did the painting, you might not be able to get the contractor to come back and fix the patch because you "helped out".


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## Genec (Jul 18, 2009)

Ok, here is what happened. This was a popcorn ceiling with a skylight. I removed all the popcorn material. Contractor installed wallboard in ceiling as part of a skylight removal. He advised he did not do finish work but asked him to finish the seams. He used mesh tape and joint compound and completed (?) the repair in one session. Joint compound was thickly applied and was not sanded. I removed the mesh tape from one end and all the joint compound and applied paper tape with EasySand90. Left the other end alone. Smoothed out entire ceiling using Easy Sand 90, dry sanded between applications, and used a final coat of lightweight joint compound and sanded. Waited about a week.

Used BM’s Acrylic All Purpose Fresh Start 023 primer - waited 24 hours and then 2 coats of BM’s Waterborne Ceiling Paint 508 (3 hours between coats). After about a couple of days saw a hairline crack in the ceiling, used a razor blade scraper to remove the paint, removed all the joint compound and planning to repair the same way the other end was repaired (paper tape and EasySand90).

My question: was it normal for the paint to come off in ribbons after two weeks? Noticed that the part that came off easiest was where there was solid joint compound as opposed to a skim coat.


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## Matthewt1970 (Sep 16, 2008)

Strange. I have used Freshstart before with no problems. Any chance you mightbe on well water with salt added as a water softener? That cold have effected the easysand mix. You also may need to let the paint go through it's 29 day curing process before it is fully adhered.


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## Genec (Jul 18, 2009)

Thanks, Matt. I went by the BM store earlier today and that is exactly what they said. The paint will peel off easily before it is fully cured and then harden in 30 dyas since it is an acrylic.

Regarding the joint repair. Anyone know how far back from the tape I have to chip the joint compound to repair the joint? Usually you have to have the width of a sheetrock knife that goes beyond the tape width. But since I am redoing the joint on either side of the tape the jc is about a 1/16th of an inch thick from the previous buildup. So far I have chipped/scraped enough away to fit the tape over the joint but am wondering how wide I will need to effectively bury the tape.


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## Sir MixAlot (Apr 4, 2008)

Genec, You might want to put a couple of screws on the old drywall side of that repair to reduce any movement = (cracks). :thumbsup:


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## ARI001 (Jun 26, 2009)

It may be easier to cut the patch out and start over. Mix a lot is correct add some screws to the surrounding drywall. The cracking can be caused by a lot of different things. Applying joint compounds to heavily will in itself cause cracking. Quick drying formulas cure chemically and may not be dry underneath. As more compound is applied and the moisture tries to escape cracking occurs. Also improper mixing will affect how the product performs. I went away from quick drying compounds for the most part a long time ago. I prefer standard heavyweight compound for tape and base coats. Lightweight for skim coats.

Mesh tapes are better suited for crack repair than taping. I prefer paper tape in areas that are relatively dry. However, I do use a variety tapes depending on the application and location. When you apply your base coat for patchwork you want it to completely cover the tape. A build of up 3/32 of an inch should be sufficient. You don't need to worry to much about making it pretty just get it on. Let this dry 24 to 48 hours. Next apply your skim coat and fur out approximately 6" to 8" on either side of the joint. Make sure you pull this coat tightly. Let it dry overnight and then lightly sand.


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## Genec (Jul 18, 2009)

10:17 I have done all that is suggested and now on my third coat I am seeing small cylindrical sort of like long oval bumps form under the tape. What could that be from and what do I do now?

Update: 10:54 - the bumps have disappeared! Still don't understand what happened. Can anyone help? Probably needs a light sanding and touch ups for a couple of small depressions. I am concerned when I prime that they might come back since I am not sure what caused them.


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