Once you’ve learned the basic skills of using a power drill, it’s important to thoroughly understand all of the various bits and accessories that make your drill such a versatile tool.
The term “drill bit” is limited to bits that fit into your power drill and drill holes. These are different from “driver bits” which fit into your drill and work as the power tool version of a screwdriver. It’s an easy mistake to refer to both groups as drill bits, but knowing the difference will not only help bring clarity to you and the people you’re talking to, but it will also make you look like you know what you’re talking about. The key to remembering the terms is to attach the appropriate verbs: a driver bit drives screws, while a drill bit drills holes.
A spade or paddle bit (also known as a wood-boring bit) is a different kind of drill bit that can be used for wood, plywood, and some plastics. Rather than drilling through the material in a spiral, this bit has a paddle at the bottom with several sharp points and a sharp bottom edge that cuts through the wood as it spins around. Spade bits should only be used for drilling holes perpendicular to the surface.
Speedbor Max bits (which is an Irwin brand term) are essentially 3D spade bits. Rather than being a paddle shape, they combine the features of a twist bit and spade bit. The tri-flute design allows the bit to move wood shavings out of the hole for faster drilling. This is very handy on the job site, but maybe not as important to the average DIYer.
When to use spade/paddle bits
Spade bits have various uses, the most obvious of which is that they come in larger sizes than twist drill bits, so if you’re drilling a larger hole a spade bit will be your go-to. Spade bits do come in smaller sizes, and I have learned from personal experience that there are times when drilling a ¼” hole with a twist bit has resulted in really bad tear-out, whereas a spade bit has given me a perfectly clean hole (did anyone catch the DIY rug loom I made?). Despite the fact that the center and side points on a spade bit don’t give you a flat-bottomed hole, these bits are great for drilling holes partway through the material.
When not to use spade/paddle bits
The times when it’s best to not use a spade bit include: drilling angled holes; drilling through unique material like metal, concrete, tile, or glass; when drilling a partial hole where the center point of the bit drills all the way through the wood and is visible; or when trying to make a smaller hole larger. Because the middle point of contact is so important, it’s pretty much impossible to make an existing hole larger with a spade bit (unless you have superhuman strength).
Spade/paddle bit best practices
A larger spade bit (one with three points) takes a little bit more skill than using a twist drill bit. Because spade bits can be larger than twist bits but have fewer contact points when getting started, they’re more prone to getting stuck or creating kickback for your drill—so it’s important to protect your wrist from getting tweaked by bracing your arm against the drill. Start drilling with high speed and light pressure until the bit comes fully into contact with the wood. Once you have contact, more pressure may be needed to drive the bit through the material. If the bit gets stuck and doesn’t seem to be making progress, try clearing away wood shavings from the bottom of the bit and then trying again.
Just like with a twist bit, you can add tape to the bit as a guide for drilling a hole to a specific depth. Applying tape to the surface of the wood will create a cleaner entry for drilling. Clamping your wood onto a scrap piece or drilling until the center point breaks through and then flipping the wood around and drilling from the opposite side are both ways to prevent tear-out on the backside.
While twist bits are an all-purpose choice for drilling, understanding and using spade bits will allow you more flexibility in how you execute your DIY projects. We hope this explainer helps you pick the best drill bit for your next project! To learn more about drill bits, check out our <episode on twist bits>, or see our full Tools 101 series.