Choosing the right router bits can be challenging, especially with the wide variety of options available. While starting with a large set can be helpful for learning, it’s worth investing in high-quality versions of the bits you use most frequently. In this blog post, I will discuss what to look for in router bits and share my essential bit recommendations.
Router bits have different shank sizes, which should match the collet size of your router. The two standard shank sizes are ¼” and ½”. Trim routers typically use ¼” shanks, while full-sized routers use ½” shanks but often come with a ¼” collet as well. For heavy routing tasks that involve removing a lot of material, ½” shank bits are recommended due to their reduced flexing. For light or detailed work, such as chamfers, roundovers, inlays, and sign making, ¼” shank bits in trim routers are excellent choices.
When it comes to bit design, spiral bits are generally superior to straight bits. Spiral bits have fluted cutting edges that wrap around the bit, resulting in cleaner cuts, cooler operation, and less stress on the bit and router. As a result, I no longer use straight bits and prefer spiral bits, particularly compression spiral bits.
Router bits can be categorized into several general types. Groove cutting bits are commonly used for cutting grooves, dados, rabbets, and waste clearance for inlays and flush trimming. I recommend using spiral bits for these tasks. Flush trim and pattern bits, which have bearings for guided cutting, are essential for template routing. Edge profiling bits are used to add decorative details to the edge of a board, with chamfer and roundover bits being the most commonly used. Rabbeting bits are similar to edge profiling bits but are primarily used for functional purposes. Finally, there are specialty bits for specific tasks like slab flattening, dovetailing, bullnose shaping, and rounded groove cutting. It’s best to buy specialty bits as needed to avoid accumulating bits that may not be frequently used.
Here are some of my most used router bits:
Double-bearing flush trim bit: This bit is excellent for template routing and can handle tricky grain direction and thick boards. Look for a compression flute design for clean, tearout-free cuts on both sides of the workpiece.
Compression, downcut, and upcut spiral bits: These groove-cutting bits come in different flute designs and have various cutting characteristics. Compression bits offer versatility, while downcut bits are ideal for CNC work and ensuring flatness. Upcut bits are great for rapid material removal.
⅛” roundover bit: This bit is perfect for breaking edges and adding a subtle, organic look to boards. It’s a versatile option for general edge rounding.
45° chamfer bit: Chamfers are simple yet effective details that can enhance a piece. A 45° chamfer bit allows you to create chamfers and bevels of various sizes by adjusting the depth of cut.
Slab and spoilsboard flattening bit: This is a crucial bit for removing substantial material over large areas. It’s commonly used on CNC machines but can also be used with handheld routers for slab flattening jigs. Look for cost-effective options with replaceable cutterheads.
Remember to take light passes, feed the router in the correct direction, and clean your bits regularly for optimal performance and longevity.