How to Remove Scratches From a Cast-Iron Sink

You opted for a cast iron sink because, well, it was supposed to wear like iron. So how did you find yourself researching cast iron sink scratch repair? The answer is enamel.

Cast iron does last and is incredibly difficult to damage, but it's also prone to rust. To prevent rust from becoming a problem, cast iron sink and bathtub manufacturers coat their products in enamel or porcelain. Although still quite tough, the coating on your sink is more susceptible to chipping and scratching than the cast iron underneath. You probably need to remove scratches from this coating and not the cast iron itself.

Over the course of its lifetime, your cast iron sink will come into contact with lots of metal cookware and utensils. As these metal substances slide across the surface of the sink, it's common for them to leave behind gray streaks known as pot marks. Pot marks look like scratches but don't actually penetrate the enamel coating on the sink.

Fortunately, pot marks are easy to remove. They're also quite common — so much so that sink manufacturing giant Kohler has developed a cast iron cleaner to remove them. Kohler K-1012525 cast iron cleaner in an 8-ounce bottle is readily available online as well as in hardware stores and department stores like Walmart and Target.

To use this cleaner, simply pour some onto a soft cloth and rub it against the pot marks until they go away. Applying the cleaner to a cork rather than a cloth is also quite effective, and a good reason to open a bottle of wine. When you're done, rinse the cleaner away with warm water.

If your sink truly is scratched, your Kohler cast iron sink cleaner isn't going to help. Instead, you'll need an enamel repair kit. These repair kits are readily available at most hardware stores and are easy to find. The trick is getting the right color.

Look at your sink's documentation to determine its exact color. Many enamel repair kit manufacturers match their colors to the major sink manufacturers so you can get a perfect match. If you can't find the color name, bring a friend with a good eye for color to the store with you. Test the repair kit's color on a paper plate or bowl before using it to make sure it's a match.

Sink manufacturer Cheviot suggests beginning your sink repair by sanding the chip, scratch or ding with 600-grit sandpaper. Rinse away any sanding residue and allow the area to dry. Once it has, prepare your sink repair epoxy according to the package instructions and use a small brush to fill in the scratch one thin layer at a time. Allow your repair to dry for 24 hours before using the sink.

When faced with a superficial scratch that doesn't run deep, you may be able to skip the enamel repair kit and simply buy some enamel paint instead. Again, it's important to properly match the color of your sink. If you do, you can disguise small scratches without filling them.

To prevent pot marks, scratches and chips, people are often tempted to place rubber mats in the bottom of cast iron sinks. Resist this temptation because bacteria can grow under the mats and cause permanent discoloration. Kohler specifically states that discoloration caused by these mats is not covered under their warranty. If you want to protect the sink, use metal racks that allow the sink to breathe rather than their rubber counterparts.