Even high-quality work boots may develop cracks in the sole. Though most cracks are not immediately detrimental to the overall quality of the shoe, they can become hazardous quickly if left untreated. Before you consider resoling the boots, attempt to remedy the problem with adhesive. A strong epoxy can fix a crack in a sole and last for months or even longer. Using this at-home treatment is more convenient and less expensive than professional repair or replacement, and it will likely solve the problem entirely.
Clean the sole of the boot before you begin working. Look in the cracks to make sure that pebbles, sand or dirt are not present. Flush debris out with water or gentle prodding with a toothpick, if necessary.
Insert the applicator tip of the barge cement gently into the crack. Only place the tip deep enough in the crack to ensure that the product will not squeeze anywhere else on the sole.
Squeeze the tube to fill the crack with adhesive. Remove the tube when the epoxy is as high as the tip of the tube applicator.
Press the sole straight by applying force from both ends of the boot. This pushes the crack together and forces out any excess adhesive.
Squeeze more barge cement into the crack if no epoxy squeezed back out when you straightened the sole. Scrape any excess adhesive that did squeeze out with the putty knife.
Repeat the process to fill each crack in the sole. Leave the boot on its side for 30 minutes to let any adhesive at the surface level of the sole air-dry.
Turn the boot right side up on an unfinished surface like a garage floor. Place small, weighted objects in the shoe to flatten the sole, as if you were wearing the boot. Let the epoxy set thoroughly for 48 hours.
Barge cement is available in hardware stores and some superstores.
Barge cement is a strong chemical compound, so work in a well-ventilated area. Follow any safety instruction the cement manufacturer lists on the packaging.