Although this tool works very well with parts 1/4" and larger in diameter, the product description states it is up to the machine #6 deburred screw, that's the main reason I bought it. I work a lot with #6, 8, and 10 mounting screws, cutting them to length as needed. I can use it for larger workpieces up to an inch in diameter, but to work with a #6 screw there needs to be a hole in the center of the tool that goes through the threaded hole on its back end. But this tool has a hard steel in the middle. There's no way it can hook the smaller screws.