That's been one of my go-to tools for years. I file sharpen, as recommended, lightly filing off the old burr first, then rolling the file slightly as if burnishing. It takes off alot of wood for a scraper, much like a Bowyer's Edge. The shavings are probably 3 or 4X thicker than what my Sandvik card scraper removes. It's a rougher tool that doesn't leave as clean of a surface. Perfect for everything but final clean up and chasing the last couple inches of draw length. You'll need to refile the burr after after every bow, but sharpening is quick. Like any tool, if it's dull, it's miserable.