There's nothing more frustrating than finding glue spots on your latest project as you apply stain or finish. And the old saying about an ounce of prevention definitely applies here. Glue on your fingers, “squeezeout,” and drips are common causes of glue spots. The problem is the glue is often nearly invisible when it dries. And once on the surface, the glue seals the wood grain preventing the finish from penetrating. This leaves glue spots, like you see here.
The first step is to clean up any excess glue that squeezes out of the joints. But wiping up glue with a dry cloth while the glue is wet can cause additional problems. It’s easy to spread the glue over an even larger surface area. It’s often better to let the glue dry a little before trying to remove it. Whenever I do a glueup, I like to let the glue “gel up” several minutes. Then I can scrape it off with a sharp chisel.
When glue squeezes out on an inside corner like in a drawer or the inside of a case, using a chisel can cause more harm than good. The sharp blade can easily mar the adjacent surface. The solution is a simple drinking straw like you see here. The straw conforms to the shape of the corner. The excess glue is collected inside the straw so it can't get redeposited anywhere else.
You can also keep glue from getting on the surface by masking off the area with tape before applying the glue (far right drawing below). The tape can then be easily removed after the glue has dried. Even when you remove the squeezeout, it’s inevitable that some glue is going to be left behind. So it’s a good idea to check out the surface before you apply any finish. To find it, you can wipe down the surface with denatured alcohol or mineral spirits. The area where the glue sits on the surface will remain dry and light in color compared to the darker “wet” wood. Once you’ve located these spots, use a cabinet scraper or sand the surface lightly to remove the glue. The goal here is to take away the glue and prepare the surface again before applying the stain or finish.
