Drill with a hole saw bit attachment.
image by Tiana Mortimer
Installing a door knob in a solid wood door or plumbing through drywall requires creating a large hole. A hole saw is the best tool for creating round openings in a variety of materials. It is actually a cylindrical drill bit, made from steel with a set of "teeth" at one end for sawing. Holes of different diameters can be created from a variety of hole saw drill bit sizes. Learning how to use hole saws can save time and effort on some of your home improvement projects.
Decide where you want your hole and then draw a circle to serve as your saw guide using the pencil. Use the measuring tape to calculate the center of the drawn circle and mark it. Next, choose the hole saw bit to use based on the diameter and depth of the hole you need.
Tighten the locking setscrew on the arbor to keep the pilot bit stable. Some locking setscrews require a hexagon-shaped Allen wrench for tightening while others need a screwdriver.
Mount the appropriate size hole saw bit on the arbor by passing the shank end through the opening at the bottom of the hole saw bit. The pilot bit should protrude between 1/4" to 3/8" past the "teeth" of the hole saw bit. Secure the shank piece to the hole saw bit with the accompanying hexagon-shaped nut.
Install the assembled hole saw bit into your drill. Place the shank end into the chuck of the drill and tighten securely.
Plug in your drill and put on eye protection before drilling with your hole saw. Line up the pilot bit to the center of the circle you have marked.
Squeeze the trigger of your drill, keeping a steady hand and slowly drill your hole. However, do not attempt to drill straight through the material. Instead, apply gentle pressure, drilling the hole part of the way before pulling back. Reapply the pressure, drilling the hole a little farther in before pulling back again. Repeat this process until the hole is completely drilled. This method will reduce the friction of the hole saw bit and extend its life in addition to avoid creating a splintering hole on your material.