If you need to fix a hole in a stainless steel sink, there are two main options available: welding and epoxy. Welding requires more work and training, but epoxy can get the job done just as effectively. So, instead of calling a handy man to come and fix your sink, do the job yourself and save some money.
Step 1 - Take a Mallet to the Hole
Cut a wooden block and place it in the stainless steel sink, sliding it over the hole that has to be fixed. With one hand, apply pressure on the block; then, tap the hole with the rubber or wooden mallet from under the sink. This will help to make the hole smaller which, in turn, will make it easier to patch.
Step 2 - Sand the Sink
The area surrounding the hole has to be sanded to provide a rough texture that will create a stronger bond with the epoxy. Sanding should be done on the underside of the sink rather than inside. After you've finished, clean the area using a mixture of 50/50 ammonia and water in a spray bottle. Wipe it away with a clean rag and make sure you give it time to dry. This will remove all impurities from the surface.
Step 3 - Apply Epoxy
Mix the epoxy according to the instructions on the packaging. Make sure you have a sufficient amount for covering the hole you're repairing. Apply the epoxy to the underside of the sink, and work it over the surface and into the surface of the sink with your gloved hands. Ensure there are no air bubbles left behind.
Step 4 - Adjust the Inside
Check the inside of the sink to make sure epoxy is not coming up through the hole. If you notice any excess, even it out by pushing it into the hole and going over the surface once more. Let the epoxy set and cure according to the instructions on the packaging.
Step 5 - Test the Patch
After enough time has passed for proper curing, turn the water in the sink on. Let it flow for a few minutes and check for leaks underneath. Test the sink a second time by placing a stopper in the drain and letting it fill with water. Let it stand for 10 minutes, checking for dripping below.
If you do not see any leakage, your repair has been successful. You can now begin using your sink just as before.