One place where you may see seams in a laminated surface is on countertops. Laminate countertops are constructed in 12-foot lengths. When you have a longer countertop, another section must be added, which creates a seam. Seams also occur in corners where two sections of countertop meet to create an L shape. Seams can't be eliminated, but they can be hidden with a seam filler that matches the laminated surface's color.
Use the edge of your putty knife to scrape out the seams; brush away the debris when finished. Pour a small amount of acetone on a clean rag and wipe down each seam. Any food or dirt lodged in the seams will prevent the seam filler from properly adhering.
Apply a small amount of seam filler on the plastic plate. Use your putty knife to mix the filler until the color is consistent. Scoop putty onto the edge of your putty knife and drag the knife across the seam. Repeat this step until the seam is filled. Seam filler will shrink as it dries so it may require more than one application to completely fill the seam.
Scrape excess filler off the countertop with the putty knife. Hold the putty knife flat on the surface and scrape toward the seam. Do not scrape across the top of the seam or you may accidentally remove filler from the seam. Brush away the dried filler and dampen a clean rag with acetone. Use the rag to clean the area around the seams.