How to Protect Stain from Glue Spots?
Whether I'm making a box or a bookcase, there is usually gluing involved. I often use white or yellow glue or something like Titebond III. No matter how carefully I apply it with brush, spreader or finger, some glue always seems to get on outside surfaces, and when I stain the piece it doesn't take in that area resulting in a light spot. Should I try to wipe the glue off as soon as it is applied, wait until it is partially set or try to cut, chip, sand, etc., after it has completely set? What about "stainable" glues: do they really work? - Dick Adler
Chris Marshall: I wait a few minutes until the glue sets up enough to skin over, then I shear it off with a dull paint scraper and wipe away anything that's left with warm water and a sponge. I aim to remove almost everything at the scraping step; wiping is just for insurance. Removing glue from end grain is tough, no matter how you clean it up; I try to keep it off of exposed end grain as much as I can. Since I always follow glue-ups with more sanding, that generally takes care of any residual glue I missed. After I'm done sanding, I wipe the surfaces down with mineral spirits to look for glue spots and sanding scratches: it works well and doesn't raise the grain.
Rob Johnstone: Glue-up is a unique step in the woodworking process. When you think about it, glue-up is one of the few irreversible steps in woodworking. (Well, you can reverse it at times...but it is a royal pain, as you'll see in this issue's other question and answer.) For that reason, it is advisable to be very methodical and careful when you are gluing things together. Use a variety of small brushes and rollers to apply a thin coating of glue to each surface of the joint. Clamp firmly, but not over tight.
When I get excess squeeze-out, I let it get firm, and then scrape it off when it is still "green." I use a combination of paint scrapers and card scrapers. I remember testing some "stainable" glue a few years ago. I was impressed - but not favorably. I did not think it lived up to the manufacturer's claims. Your best bet to avoid those annoying glue spots is to be careful at glue-up and methodical in your pre-finishing sanding.