Except for fairly small drill bits (1/2"), nothing has touched this tough Norwegian maple stump. The stump grinder did its job, but it was a lot of work. The chainsaw was able to cut off some of the protruding roots, but not the stump. Many titanium drills are simply melted (they get very hot). This drill is fantastic. and gives me 12 inch holes to put in plenty of Epsom salts to rot.