Nice handle the knurling tool we have at work is two wheels you just basically force into the piece you are turning. Is the one you use similar in function? Your knurling is way nicer than what I can accomplish with ours. Maybe our work one is wore out??
The one I used has two wheels. Do you angle the knurling tool or run the wheels flush the length of the tool? If the teeth are clean it should be fine and not worn out.