The other day I saw an ad of a tool to improve the tip of the screws and threaded rods. The tool is used with a drill and is a kind of "sharpener" for the screws.
When I cut a screw, the thread is damaged. This tool allows to touch up the damaged end giving it a conical shape.
Does anyone know what it's called or where can I buy it?
Sorry, I have a hard time explaining.