The precision of the knobby knife will allow you to sharpen your tires multiple times. The knife is 100 watts; the purpose of this is to maintain a 500 degree cutting temperature. A soldering iron is generally 60 watts which will not allow you to make multiple cuts. This allows you to cut knob after knob without waiting for the iron to reheat. It also has a nice wide blade that is perfect for a knob. With practice, you should be able to completely recut your tire in 10-15 minutes. The key is to limit the amount you remove off the width to maintain a constant width to height ratio (i.e. knob strength). Can also be used for grooving ATV, Supermoto & Roadrace tires.