The top on many tables, dressers, desks, and other furniture is made of a thin wood veneer glued to a solid-wood or processed-wood substrate. Over time, the glue bond often fails and the veneer blisters — especially when subjected to heat and moisture (such as a cup of hot tea or coffee). To repair a veneer blister, carefully slit it open with a razor knife. Then use a glue syringe or a toothpick to apply yellow carpenter's glue beneath the veneer. Press down lightly on the blister to spread the glue. Cover the repair with wax paper and a flat wood block, then clamp the blister flat. Let the glue cure overnight. Then remove the clamp and wax paper, and lightly sand and refinish the surface. Prevent new blisters by applying two coats of varnish or hand-rubbed wood oil on the veneer — and keeping anything hot or wet off the surface.