How to Mount Under-mount Sinks to Corian Tops

Lay a 2-by-4-inch piece of lumber horizontally across the sink opening in the Corian top. The lumber should extend at least 6 inches past each side of the opening.

Position the sink inside the base cabinet and beneath the sink opening in the Corian top.

Remove the sliding heads off two steel bar clamps by pushing on the release trigger located on the sliding head. Feed the bars through the bottom of the sink drain holes until the stationary heads of the bar clamps rest against the underside of the sink.

Replace the sliding heads onto each bar. Have an assistant lift the sink and place it against the bottom of the Corian top. Push the sliding heads of the bar clamps down on the bars until the swivel screw connected to the sliding heads rest against the piece of lumber laid across the sink opening.

Turn the handle of the swivel screw on the sliding heads to tighten the clamps against the lumber. As you tighten the swivel screws, center the sink beneath the Corian top.

Mark the position on the sink with a felt-tipped marker along the edge of the sink underneath the Corian top. Loosen the swivel screws and lower the sink.

Mark the positions of the under-mount sink clamps beneath the Corian top. Place two clamps at an equal distance apart on each side of the sink opening along your sink marks. Position three clamps equally spaced along the front and back of the sink opening.

Drill 3/8-inch holes from beneath the Corian top at each under-mount sink clamp location, slightly smaller in diameter than the sink clamp screws. Thread wing nuts onto each screw that came with the sink clamps. The wings must face the head of the screw.

Thread each of the screws though the slotted opening in the sink clamps. Loosely screw each screw into the underside of the Corian top, so you can swivel the clamps away from the sink opening.

Apply a bead of silicone caulk to the top lip of the sink. Lift the sink back against the underside of the Corian top, positioning the sink inside the marks you made.

Tighten the bar clamps to hold the sink in position. Swivel the sink clamps over the bottom side of the under-mount sink lip. Tighten the screws in each clamp. Twist the wing nuts with your fingers to further tighten the sink clamps against the sink.

Leave the bar clamps in place overnight or until the silicone caulk is cured.