Things You'll Need
Sandpaper or sanding sponge
Bubbles or blisters on painted wood veneer and other smooth surfaces are usually caused by moisture or vapor trapped under the paint film. This usually happens when either the surface or the air contains a lot of moisture, or if it is very hot. Although it may be alarming to see big bubbles all over your new paint job, it is easy to correct--and if you are lucky, it sometimes corrects itself. If the paint on the wood veneer bubbles up after several days have passed, you have a different problem that will take a little more work to fix.
Paint Bubbles up Within a Few Hours
Wait and see what happens if the paint bubbles up within a few hours of painting. Open windows, turn on a fan or use a dehumidifier to reduce humidity and speed drying. It may take up to 24 hours for the vapor or moisture to evaporate through the paint film, and sometimes it shrinks back down and adheres perfectly.
Scrape the bubbles away if they don't disappear after 24 hours. Remove all the loose paint with a putty knife or chisel-edged scraper. Sand the entire surface smooth with 20 grit sandpaper or a medium-fine sanding sponge.
Prime any of the bare veneer with the same primer you used initially. Wait for it to dry completely, and paint two coats over the primed areas, following label directions for drying times.
Paint Bubbles Up After a Few Days
Carefully scrape away a bubbled area of paint. If it scrapes all the way down to the wood veneer, this indicates the first coat of primer or paint has not adhered well to the veneer. Paint that bubbles away from the previous coat of paint or primer has not adhered to that coat.
Scrape the loose and bubbling paint away. This may require almost complete removal of the paint, as it may all be loose. Scrape away as much as you can, and thoroughly sand the entire surface.
Prime both bare and sanded areas with tinted shellac or a bonding primer. Allow it to dry completely, and repaint the veneer with one or two coats of paint.