Choosing the Right Drill Bit Size for Woodwork Projects

For woodwork projects, it is always important to choose the right drill bit size. There are a few challenges that come from using the wrong size wood bit. Using a bit that is too big can splinter your material, which ends up wasting wood. It can also result in holes that are too big for screws to attach properly to wood. This means loose screws and a higher chance of your entire project falling apart. Bits that are too small, on the other hand, also cause problems. These may cause wood to split if you try and add a larger screw. Holes may also end up ragged if screws are forced into holes that are too small. Then there’s the increased chance of stuck bits

With all of that in mind, having drill bits that are the right size for the holes you need to make is the best way to avoid issues. The good news is that it’s fairly easy to figure out how to get the right size bits. In this guide, we’ll share a few simple tips to keep in mind when choosing your bits.

Which Drill Bit Size Do You Need?

Here are a couple of ways that you can make sure your bit is the right size.

Get a set rather than individual bits

This is, by far, the simplest way to make sure you have the right drill bit sizes. Sets range from smaller sets of a few standard sizes to larger sets with more size options. These will save you a lot of time and effort. It’s worth spending a little more on a set. You can compare bits to your screws at home to find bits in the right size. To do this, remove all of the bits from the set packaging and line them up on your work table. Then, take one of the screws you will be using, hold it with the tip facing you, and place each bit next to the screw. The bit you will want is the one that is very slightly smaller in diameter (including the threads). 

Use a sizing chart

Wood bit sets will come with a sizing chart, which gives you exact measurements of each bit. Individual bits can be purchased by size, too. Screw sets will also come with sizing charts. If you are purchasing sets or individual products, you can match up screw and bit sizes without comparing them side-by-side. 

Use smaller bits for pilot holes

For pilot holes, you want to choose a smaller bit that is narrower than the screw. Using a bit that is too small may end up increasing the risk of wood splitting when you add a larger bit to widen the hole and add the screw. A larger bit isn’t ideal for pilot holes, either, as it will make it harder for the screw to grip the wood inside the hole. Ideally, you want to use a bit that isn’t too much bigger than the screw.

Remember that countersinks can affect bit size

If you are using a countersink, the size will vary. This bit has two cutting points, which include the bit as well as a triangular cutting edge near the high end of the bit. This edge cuts into the board when the bit gets deep enough into the wood. There will be a larger hole around the smaller shaft hole. This means that the screw head can be pushed to meet the surface of the wood. The bit shaft length will need to be considered, along with the diameter, which will need to be very close to the screw head size. 

Ruwag offers a range of sets for your projects, with a selection of sizes available in each set. Our sets include sizing guides along with recommended drilling speeds for each bit in the set. If you’ve got any questions about choosing the right drill bit size, get in touch and we’ll be happy to help.

Photo: iStock/svengine