Quote from: tgbto on March 13, 2026, 10:23:36 AMI'm not sure the truing tool restores the "cutting efficiency" of the stone.
I guess it depends on what you mean by efficiency. A freshly-trued stone definitely cuts steel more aggressively. I wouldn't sharpen a good knife on a freshly-trued stone. It removes too much steel from the knife blade. I would find my dullest chisel, lawn mower blade, or other tool to sharpen on a freshly-trued stone. In fact, I often keep a dull tool handy to be sharpened immediately after truing.
Ken is absolutely right about truing often and lightly. Not only will it give you better results, it's more economical. Because an out-of-round grindstone will very quickly get more and more out of round as you use it and you will have to remove a lot of material to get it round again. A grindstone will last longer if you keep it from getting out of round by truing it often.
It's kinda like brake pads and rotors. Putting new pads on a rotor with a rough surface will make the pads wear faster. It's more economical to machine the rotors when replacing the pads.