I've noticed some marking knives come with carbide blades, and I'm really curious about their longevity. How much longer do these edges actually last compared to standard steel? Also, how do you sharpen them when they do get dull? Are there any downsides to using carbide besides the cost?
3 Answers
Honestly, carbide in a marking knife seems a bit overkill. It tends to be more brittle, which means if you're not careful, you might chip the edge. You usually want a softer blade for wood, and sharpening carbide is a different ball game since you'll need diamond files or stones for that. Personally, I think a good steel knife does the job just fine unless you have a specific reason to go carbide.
Carbide marking knives can last a long time, theoretically, but they come with their own issues. Benchcrafted sells one, and while it's sharp and lasts longer on paper, it can chip easily. I'd rather use a tough, abrasion-resistant steel for marking so I don’t have to worry about breakage. It’s just not worth the risk or hassle!
I’ve had a similar experience with some old tools. I have a Czech Edge awl that's carbide, and it’s delicate. If it’s too pointy, it chips easily. A well-maintained steel knife is more practical for marking. Plus, if you drop tools like I tend to do, a steel knife is much more forgiving!