New cabinet doors and drawer fronts typically don't include knobs so that homeowners can choose such details based on their decor preferences. The process of adding knobs isn't difficult if you have the right tools. The fitting and installation of cabinet knobs depend on the right drill bit, which is usually 3/16 inch.

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Knobs on kitchen cabinets.

The Right Bit

The majority of cabinet knobs are packaged with #8 machine screws, which measure 0.16 inch, or roughly 5/32 inch, in diameter. Use a 3/16-inch bit to drill the hole. The screw should fit through the hole without binding. If the screw is too tight, use a drill bit progressively larger by 1/16 inch until the screw slides through the hole with little or no resistance. If you have numerous holes to drill, fabricate a small template out of wood or cardboard to indicate hole positions on the drawer or door.

Screw Length Is Important

Screw length is often overlooked when installing drawer knobs. Manufacturers typically provide screws with adequate length for 3/4-inch-thick material. If your drawers have additional layers, or use undersized material, the provided screw length may not be appropriate. In general, the screw length should be 1/4 inch longer than the thickness of your cabinet door or drawer front material.