It is theoretically possible, but I have never seen any evidence that this actually happened. I tried on TC to get just 2 mods maxxed using smith tools, and after 100 attempts hadn't managed. You can't use a copper hammer, because they just don't have enough power to make something like that, same with a bronze hammer it seems. To get 3 at the max, I am guessing you need to use the 25 charge tools, but now you only get 4 tries per tool. Trying with a 15 charge tool will give you extra mods, every time.