Hi fellow painters had a few blisters in my painted wall,the wall was cleaned ,our Wooster Dustbuster
so it wasn't dirt allow plenty of drying time for paint ,but its an outside wall so wondering if that could
be a part of the problem instead of leaving 4 hours being its cold go for longer.We sanded back ,and
coverstained but not back to the bare plaster then filled that may of helped,us.Now theses few blisters
are becoming a pain,for experiment i used a needle pricked the middle of blister putting slight pressure
on with my thumb and it worked,i am going to sand and gardz wall to see if it doses it again ,there is a
wooden window thats gets a lot of moisture ,and i am certain this is a moisture problem.