How to Countersink Screws

A Quick and Easy Tutorial on Countersunk Screws

If you are new to woodworking, you may have seen the term “countersunk screw” used in joinery. What exactly is a countersunk screw? Why countersink a screw? I’ll explain this method and even show you how to countersink screws!

What is a countersunk screw?

A countersunk screw is a screw that is “sunk” into a piece of lumber. The head will sit below the surface of the material and it can easily be filled with a wood plug or filler. Bolts and large hex-head screws can also be countersunk. Each require a special countersink bit for the best results.

Why would a countersunk screw be used?

Countersinking a screw is one of the many methods of joining one piece of material to another. It makes a very strong, tight joint and is used in places where other joinery is not practical. In other words, if you don’t want to have to fill a bazillion pocket holes, countersink a screw instead. The hole is smaller and easier to fill. Most of the plans on my site can be constructed using countersunk screws instead of pocket hole joinery with just a few modifications!

First, you will need a countersink bit. I recommend purchasing a countersink bit set (<– affiliate link!). This way, you have a different size bit for different size screws. A countersink bit has a regular drill bit at the end to drill a pilot hole as well as a step or two to create a larger hole for the screw head and a plug to fit into.

Mark the position on the board for the countersunk hole. Drill the hole being careful to to move or wiggle the bit as it can break. I know this from experience and have broken plenty of bits!