Are you getting work done around the home? Do you feel you handier than simple home fixes? Why not look into something like Burnishing?
What burnishing means is using a smooth hard tool to rub against metal. What this does is make the metal much harder and reinforces it. This is also typically a cold process, where water is poured onto the tool so that the metal doesn’t crack. So using a burnishing tool for metal can greatly improve the quality of the metal you’re working with. There is also such a thing as diamond burnishing, but what this process captures is the essence of smoothing over an object to make it harder.
This answers the question of what do you use a burnishing tool for. So why might this pique your interest? Well, there are in fact professionals who specialize in this process. It is not a simple cakewalk to burnish something correctly. If you are too rough, the surface you are burnishing can easily crack. So if you do consider doing this as a profession, it helps to be meticulous.