# Can't get rid of air bubbles - at least 5 coats now



## saltcod

Hey guys,

I'm in a bit of a pickle. 

I'm trying to plaster over walls with paint on them. Not sure if it's oil or latex—I just know that it's green 

Right from the first coat, I'm getting lots and lots of air bubbles. Not just a few, but LOTS. It's almost like there's yeast in the plaster. It bubbles like crazy. Not big blisters, but very small ones.

I tried putting on a thick coat of normal CGC plaster, as well as a good thick coat of dustless CGC, with the same result. On some sections of the wall there's a very good thick layer of plaster which should be porous enough to not have bubbles, but no sir! I get bubbles every time. 

Even when I put on very, very thin skims of plaster over well-dried areas, it still bubbles like crazy. And I'm talking about putting the thinnest skim possible over an area that already has about 4 good layers of plaster. Bubbles, bubbles, bubbles.

I've tried:
- Whipping the plaster a lot
- Whipping the plaster a little
- Working the plaster to death on the hawk
- Applying a thin coat directly to the paint
- Applying a thin coat over 4-5 layers of well-dried plaster

All with the exact same result. Hundreds of bubbles. 

ANY help is very welcome. I don't know what I'm going to do. I've gone over and knocked the tops off the bubbles and filled them in numerous times, but the bubbles always come back. There's no getting rid of them! I've only ever plastered over fresh, unpainted drywall, but still, if I put several good thick coats of plaster on a painted wall, that should work shouldn't it?

Thanks

Terry


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## joepro0000

Maybe fill it in with some vinyl spackle or caulk?


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## penandscale

saltcod said:


> Hey guys,
> 
> I'm in a bit of a pickle.
> 
> I'm trying to plaster over walls with paint on them. Not sure if it's oil or latex—I just know that it's green
> 
> Right from the first coat, I'm getting lots and lots of air bubbles. Not just a few, but LOTS. It's almost like there's yeast in the plaster. It bubbles like crazy. Not big blisters, but very small ones.
> 
> I tried putting on a thick coat of normal CGC plaster, as well as a good thick coat of dustless CGC, with the same result. On some sections of the wall there's a very good thick layer of plaster which should be porous enough to not have bubbles, but no sir! I get bubbles every time.
> 
> Even when I put on very, very thin skims of plaster over well-dried areas, it still bubbles like crazy. And I'm talking about putting the thinnest skim possible over an area that already has about 4 good layers of plaster. Bubbles, bubbles, bubbles.
> 
> I've tried:
> - Whipping the plaster a lot
> - Whipping the plaster a little
> - Working the plaster to death on the hawk
> - Applying a thin coat directly to the paint
> - Applying a thin coat over 4-5 layers of well-dried plaster
> 
> All with the exact same result. Hundreds of bubbles.
> 
> ANY help is very welcome. I don't know what I'm going to do. I've gone over and knocked the tops off the bubbles and filled them in numerous times, but the bubbles always come back. There's no getting rid of them! I've only ever plastered over fresh, unpainted drywall, but still, if I put several good thick coats of plaster on a painted wall, that should work shouldn't it?
> 
> Thanks
> 
> Terry


try using some vario should solve the problem.


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## cazna

Here you go http://www.drywalltalk.com/f7/air-bubbles-when-mud-over-paint-62/index3/#post24586

Thin coats not think, tThe thicker the coat the bigger the bubbles. Add a little dishwash liquid, one tablespoon per bucket, dont over thin, dont over mix, put mud on wall wait a minute or so, remove mud then re apply, Its always diffacult not to get the bubbles but these tips will help


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## silverstilts

saltcod said:


> Hey guys,
> 
> I'm in a bit of a pickle.
> 
> I'm trying to plaster over walls with paint on them. Not sure if it's oil or latex—I just know that it's green
> 
> Right from the first coat, I'm getting lots and lots of air bubbles. Not just a few, but LOTS. It's almost like there's yeast in the plaster. It bubbles like crazy. Not big blisters, but very small ones.
> 
> I tried putting on a thick coat of normal CGC plaster, as well as a good thick coat of dustless CGC, with the same result. On some sections of the wall there's a very good thick layer of plaster which should be porous enough to not have bubbles, but no sir! I get bubbles every time.
> 
> Even when I put on very, very thin skims of plaster over well-dried areas, it still bubbles like crazy. And I'm talking about putting the thinnest skim possible over an area that already has about 4 good layers of plaster. Bubbles, bubbles, bubbles.
> 
> I've tried:
> - Whipping the plaster a lot
> - Whipping the plaster a little
> - Working the plaster to death on the hawk
> - Applying a thin coat directly to the paint
> - Applying a thin coat over 4-5 layers of well-dried plaster
> 
> All with the exact same result. Hundreds of bubbles.
> 
> ANY help is very welcome. I don't know what I'm going to do. I've gone over and knocked the tops off the bubbles and filled them in numerous times, but the bubbles always come back. There's no getting rid of them! I've only ever plastered over fresh, unpainted drywall, but still, if I put several good thick coats of plaster on a painted wall, that should work shouldn't it?
> 
> Thanks
> 
> Terry


 I had the house from hell years ago that I had a similar experience, only they wanted a respray. I was using durabond at the time repairing the cracks which seemed the second it touched the ceiling it would instantly start setting up. What a nightmare. Then finally got that all done masked off the whole house (with all the stupid nick knacks on the walls and major furniture that filled most all of all the rooms) textured it pulled down the masking only to see large areas of the ceiling pillowing down separating from the old plastered sand finished texture. Told the homeowner i would have to come back once it dried to scrape it down and start all over. So I did only to have it happen a second time. I don't know what type of paint was on there perhaps some old lead based paint. The homeowners were very nice about it, paid me which I didn't see why they would after all that and said they would just put in a suspended ceiling (yuck).. I was so relieved, If I had to remask it off a third time I would have come unglued that is for sure.


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## moore

Each pass has to completely dry before the next. 
this helps, less bubbles. vario same, has to cure before next pass.
sand down the area ,,,/plaster/ paint before you start . this gives the compound a better bond. vario TUFF STUFF.


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## raven

the air bubbles are because the drywall is sealed off from the paint . there is no where for the moisture to absorb so it comes back throuth the mud causing the air pits. try using a product from sherwin &williams called drywall conditioner. roll on passed where your going to mud , let drie then back sand with 100 grit, should work.


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## 2buckcanuck

COOL !!!!! our 1st newfie on drywall talk, you guys are the funnest guys to work with on a job site. and no one can drink you guys under the table:thumbsup:

Just to add another tip,coat the wall then let it stand for a while, 3 to 5 minutes, you will see all the little bubbles appear, then wipe it down. It can still take multiple coats though. Do opposite strokes with the trowel/knife too.


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## roominaday

Priming with Coverstain 1st can help. I will usually get my coats to the level I want, sand, prime and then just skim the left over bubbles again with lightweight Spackle, or Sheetrock 20 and them spot prime again, or use the Dap pink stuff as it doesn't flash. We use Aura paint mostly, self priming. Make sure each coat is 100% dry as others have said.

Saltcod - I am an honorary Newfoundlander - I have kissed the cod and been Screeched in!


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## 2buckcanuck

roominaday said:


> Priming with Coverstain 1st can help. I will usually get my coats to the level I want, sand, prime and then just skim the left over bubbles again with lightweight Spackle, or Sheetrock 20 and them spot prime again, or use the Dap pink stuff as it doesn't flash. We use Aura paint mostly, self priming. Make sure each coat is 100% dry as others have said.
> 
> Saltcod - I am an honorary Newfoundlander - I have kissed the cod and been Screeched in!


Just so they know what your talking about roominaday
http://cansomebodyhelpme.com/screechin/screech-howto.pdf


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## roominaday

I have the "Diploma" somewhere! Thanks 2buck!


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## SlimPickins

We touched up and painted (latex) a plastered bathroom one time and the paint started coming off like a balloon ...we scraped it while it was wet (it came off reeeaaal easy), let it dry, and then primed with an oil base to keep the water from getting to the plaster. Worked like a charm.


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## carpentaper

i always get a few problem spots on every job with painted walls. i don't even worry about them. i do my first coat like normal but a little wider than usual. next day when it is totally dry. i run around real quick and fill all the bubbles with my six inch knife going back and forth over them until i am sure they are full. i wipe off everything that i put on just leaving the bubbles full. after that i do my second coat as usual. i have not had a problem with this method. i still always budget for a third coat over any painted surface. making your first coat much wider than necessary helps too. i don't go much further on my next coats or i am more likely to keep getting bubbles. with this method i only have bubbles on the first coat.


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## rebel20

Go to this thread where I fixed my dads hallway the paint is more than likely lead based underneath and if I remember as a kid the top coat of paint was latex.
http://www.drywalltalk.com/f9/review-vario-tapeless-mud-824/ I had 1" area of bubbles waited 2 min and swiped it and they were gone, and I think that was due to a dirty wall I am waiting till my daughter gets to Michigan to have her take a few pics it was over a year ago.

rebel


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## Final touch drywall

We always prime first with a zinsser cover stain sealer prior to skimming over any existing work.


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## saltcod

Hi Guys,

Just a quick followup for those reading after. First, thanks a million to all the replies - very helpful. 

In the end, I put an oil-based coverstain over the paint. Worked like a charm. The bubbles are now gone.

Thanks x 10 from the forum's first Newfoundlander. =)


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