Q: I recently applied a sheet of "peel and stick" veneer to a cabinet end panel. The cabinet looked fine from time of application until several weeks after installation. Now many bubbles appear under the veneer. How can I avoid this in the future?

A: I believe that the main problem is that the veneer is not well attached to the panel.

Next time, very lightly sand the panel before you apply the veneer. Then remove the dust, perhaps using a rag with a bit of isopropyl alcohol on it. Alcohol is non-grain-raising.

Why is this suggested and why does it work? Oftentimes, a panel is not active for gluing (there are a lot of spots for the adhesive to attach to the wood) due to the panel's age, dusty surface and so on. Sanding reactivates it, so you will get a very strong bond.

In rare cases, the panel substrate or the adhesive emits gas and this gas creates pressure that causes the bubbles. This is called off-gassing. I have heard of it, but never encountered it.

In extreme cases with lots of moisture changes (such as close to a sink or stove), which causes large differences in movement between the veneer and substrate, you can expect problems no matter what. Such a problem will show up as having the bubbles or cracks all running the same direction (along the grain).

Sometimes you can repair bubbles by popping them with a pin or making a small knife cut in the center and then re-gluing them using a little heat to try and reactivate the adhesive.