Step 2 · Drill the Mounting Hole

This is the step most people slow down on. Take it one move at a time — there’s no rush, and you can rewind the clip as many times as you need.

Choose a suitable location for the air switch button on the sink deck, typically opposite the faucet handle. Ensure there's clearance underneath. Use a tape measure and marker to mark the center of the hole. For a stainless steel sink, use a center punch and a hammer to create a small indentation at the mark; this prevents the drill bit from wandering. Start by drilling a small pilot hole with a 1/8-inch drill bit. Then, use a step drill bit or a metal-rated hole saw of the correct diameter (typically 1-3/8 inches, but check your air switch kit instructions) to enlarge the hole. Apply cutting oil to lubricate the process and keep the metal cool. Once the hole is drilled, use a deburring tool or a small metal file to smooth any sharp edges around the hole's perimeter.