A scratched porcelain sink is an unsightly reminder that no surface in a home is immune to being damaged. You can fix a scratch in a porcelain sink yourself, providing you have purchased a few supplies from a hardware store. A few household items will be needed as well -- most homes have them already. No bulky or costly tools will have to be bought or rented.
Apply distilled alcohol to an edge of a soft cloth. Wash off the scratch and the surrounding area with the edge of the soft cloth. Rinse off the scratch and the surrounding area with another edge of the cloth, moistened in tap water. Dry the scratch and the surrounding area with a dry soft cloth.
Mix the contents of an epoxy kit in glass bowl according to the directions. Dip the end of a toothpick in the epoxy mixture. Insert the epoxy-covered tip of the toothpick in the scratch. Deposit the epoxy in the scratch. Apply more epoxy to the toothpick and repeat this procedure until the scratch is completely filled with epoxy.
Moisten a cosmetic sponge in tap water. Place the sponge on the sink against the left side of the scratch. Push down on the sponge. Move the sponge along the length of the scratch to remove the excess epoxy. Remove the sponge once it has reached the end of the scratch. Let the epoxy set for a day.
Open the can of porcelain paint and stir it with a wooden dowel. Dip a model paintbrush in the paint. Place the paintbrush on the sink against the left side of the scratch. Push down on the paintbrush. Move the paintbrush along the length of the scratch. Remove the paintbrush once it reaches the end of the scratch. Let the paint dry for a day.