Poke a hole in the top and bottom section of your maple veneer bubble with a needle. The holes should go through the veneer backer but not into the wood below.
Preheat a clothing iron to approximately 190-degrees Fahrenheit or between the cotton and wool settings.
Place a large piece of felt or heavy-duty craft paper over the blister area. Use a marker to outline the blister area.
Apply the warmed iron to the blister area and work it in small circles. Do this for approximately 10 minutes or until the area is nice and hot. Put the iron and the felt/cloth to the side.
Press down on the blister with a metal wood scraper. You may need to reheat and apply pressure a couple times to get the bubble to lay completely flat.
Put the scraper to the side. Use a flat-bottom frying pan to apply pressure to the blister area. Apply a bit of denatured alcohol on the wood surface as the temperature of the wood cools down. Keep doing this until the area has cooled completely.
Moisten a lint free cloth with the denatured alcohol and clean the surface. Allow the area to set for at least four hours.
Lightly sand the area to make it smooth again. Apply a thin coat of wood sealer and then finish the wood with a lacquer or other finishing product.
Use a razor blade to make a slit in the bubble, running the cut with the grain of the maple veneer.
Use a toothpick or equivalent to scrape the glue out from under the bubble.
Apply some wood glue into the bubble area. Wipe any excess glue away from the area with a paper towel or washcloth.
Place some heavy-duty craft paper over the bubble area and apply pressure with a preheated clothing iron. It should be between the cotton and wool settings or at 190 degrees Fahrenheit. Work in small circles for about 10 or 15 seconds. This should be enough time to allow the glue to set.
Sand off any excess glue and rough edges. Apply wood sealer over the area and then apply finish to the wood.