The Buyer’s Guide to Diamond Router Bits

The Buyer’s Guide to Diamond Router Bits
Diamond router bits are cutting tools used to polish profiles and hard surfaces like stone and concrete. They feature diamond grains on their working parts. Though simple in appearance, several key factors need consideration when buying one for cutting or polishing tasks.
1. Router Bit Shanks
Shanks are the solid, cylindrical parts of diamond router bits, available in two main sizes: ½ inch and ¼ inch. Larger shanks offer better stability, smoother cuts, vibration resistance, and longer lifespan. Not all routers support both sizes, but some accept interchangeable bits.
2. Cutting Edge Material
Diamond router bits typically use carbide or high-speed steel (HSS) for their cutting tips. Carbide is preferred for its higher hardness and longer edge retention compared to HSS. However, carbide is more fragile and brittle, requiring careful handling and storage.
3. Bit Quality
Assessing diamond router bit quality isn’t straightforward with just a visual check. Key indicators include a carbide tip, a sufficiently fine and thick cutting edge, and secure brazing.
4. Bit Design
Router bits should be designed to minimize kickback risk. This means a larger size to prevent deep material penetration and reduce heat buildup, helping maintain sharp edges longer.