How to Prepare Wood for Flat Head Machine Screws

Determine the size of the machine screws you will be using on your wood project. Take the screw (or screws) with you to your local home improvement store and get drill bits for your drill that match the width of the screw itself, or slightly smaller if you want the screw to have a tight fit. Pick a 1/8 inch drill bit for a 1/8 wide screw, for example, so that the screw will easily slide into the hole once you have drilled it.

Purchase washers and nuts (if applicable) for the back side of the wood project. Mount the washers and nuts on the opposite end of the flat-head machine screw to keep it locked in place and the wood between the flat head of the screw and the washer and nut firmly together.

Mark the wood in the areas you want to place the flat-head machine screws. Place a drill bit into the end of your hand-held drill and tighten the bit according to the manufacturer's instructions (different drills have different methods of tightening the bit in place). Place the tip of the drill bit over the mark and apply pressure while you press the trigger of the drill. Allow the bit to work its way through the wood completely, and then pull it back out of the same hole while keeping pressure on the trigger so that the reverse pull cleans any additional burrs out of the hole. Repeat this process for every hole required.

Slot your flat-head machine screws through the holes in the wood and use the washer and nut on the opposite side. Slide the bolt through the hole, then slide the washer on the end of the protruding bolt, thread the nut on the end of the bolt and tighten accordingly with the screwdriver on one end and the wrench on the other.