Over the last 30 years, carbide saw blades have almost completely taken over from regular steel saw blades for woodworking because carbide lasts so much longer between sharpenings. In this case the term “carbide” refers to an extra-hard alloy that’s used to form the cutting teeth arranged around the circumference of a blade. Carbide teeth are typically brazed to the main body of the blade, and it’s the incredibly hard nature of carbide that makes these teeth last so long, while also presenting a challenge when it comes to sharpening.
Inexpensive carbide saw blades of the sort used in hand-held circular saws are designed to be used then recycled, while more expensive carbide blades for tablesaws and chopsaws are built to be resharpened 4 or 5 times. Even in a professional shop, these blades deliver years of service.
There are two ways that the teeth on carbide blades can be sharpened. You can send a blade out to a dedicated sharpening shop, or you can invest in the equipment to do the work yourself. I have almost a dozen carbide saw blades in my woodworking shop, and a couple have been with me for almost 20 years. I’ve always sent my blades out to be sharpened. Costs typically run from $10 to $15 per 10- or 12-inch diameter blade and the results have always been excellent. Performance after a fresh sharpening job is at least as good as when the blade was new. I don’t live anywhere near a sharpening shop, so I wait until I have 3 or 4 dull blades to package up and ship by mail.
There are a few small scale machines designed for DIY sharpening of carbide saw blades, and one that I know of is made by Viel (www.vieltools.com) I’ve never used this machine personally, but a friend of mine with a welding shop just bought one. I’ll know better how it works in a few months. Besides having the necessary sharpening equipment, it does take skill to restore carbide saw blade performance. Some blade designs are easier than others to sharpen, but either way you should expect to invest some learning time for you get good.
Why would someone with a welding shop need to sharpen carbide saw blades? Over the last few years carbide metallurgy has progressed to the point where it’s tough enough to handle heavy ferrous metal. So-called “dry cut” carbide blades are available for cutting all kinds of steel, both solid and hollow. Performance is quite surprising and much better than traditional abrasive wheels. Carbide blades cut faster, they generate far fewer sparks, they’re very accurate and leave no burr. The cut surface is also cool to the touch. To see a metal cutting carbide saw blade in action, check out my video at http://www.SteveMaxwell.ca/metal-cutting-blades
Contributing Editor Steve Maxwell has been helping people renovate, build and maintain their homes for more than two decades. “Canada’s Handiest Man” is an award-winning home improvement authority and woodworking expert. Contact him by visiting his website and the blog, Maxwell’s House. You also can follow him on Twitter, like him on Facebook and find him on Google+.