Basic Repairs for Formica and Corian Countertops
Several different materials are used to manufacture countertops, and each is treated differently when it comes to repairs. Two practical types are: 1) plastic laminate, usually referred to by the brand name Formica, and 2) solid surface, often referred to by the DuPont brand name Corian.
These surfaces are subjected to numerous abuses, causing various kinds of damage, each with its own solution. I'll touch upon the most common.
Laminate Problems and Their Fixes
Glue failure. Laminate countertops are durable and inexpensive. One of their most common problems, though, is failure of the glue binding them to the substrate. This typically happens at the edges and seams. If the bond is weak at any point, moisture can invade and start the process of delamination. If caught early enough, before the damage spreads or before contaminants (such as dirt or food) infiltrate, they can easily be repaired with the proper adhesive. Laminates are initially bonded with contact cement, which is what you want to use if a fairly large area is involved. However, many experts recommend GOOP brand glue for smaller areas such as edging. Clean the area, apply the glue per instructions, and tape the piece in place while the glue sets. If it's a flat horizontal area, weigh it down with phone books. Cracks and tears can also be reglued. Always read the instructions before you use any glue, as most function differently from each other.
Gouge or scratch. Gouges and scratches can be repaired with colored epoxy or similar products. Slight surface burns can sometimes be scrubbed away with a mild abrasive cleanser. Serious burns usually require replacing the surface altogether. Sometimes you can resurface laminate over laminate; sometimes you can remove the old laminate and replace it; and sometimes you just have to replace the entire countertop, which isn't as painful as it sounds. Often you can buy premade countertops at your local home improvement store, which may be less expensive than a repair.
Solid Surface Problems and Their Fixes
Solid surface countertops are completely different: they're far more durable, which means they last much longer. In addition, you don't have to worry about burns. Solid surface cost more than laminate countertops, but you'll save in the long run.
Scratch, gouge or chip. Light scratches can be sanded with a fine grit wet sandpaper, and gouges and chips may be filled with paste-type products, much like filling a fender dent on your car.
Breaks. Breaks can be easily reglued if they're small enough or in an unobtrusive place. However, a large break might require the touch of a professional in order for the repair to be invisible.
This is a broad subject with a lot of "sometimes" involving a lot of different solutions, many of which are easily tackled for little expense. As with most home repairs, common sense is key, and when in doubt, ask an expert.
Updated May 9, 2018.