I've been using this to grind down and shape an anvil out of a chunk of railroad track steel. It is doing the job well, more precise than a grinding wheel and longer lasting than a flap disk.My only complaint is that I had to find a different nut to be able to using it on my angle grinder. The typical method of fixing disks on there will not work with this because the inside of the cup is too narrow for it to sit down inside and attach to the shaft. This also makes it to where I will still have an excess amount of the cup itself left whenever it reaches the point where the nut will be hitting the surface before the cup does.