I picked up this dotting tool recently. It's got this arm that responds to the teeth and a little gear underneath this clip and wheel. It actually came with a couple different wheels. They have different dot patterns for dashes and uneven and space dots. You got to set the nib up and dip it in ink. Then you drag it along a straight edge. Every time that arm clicks into one of the teeth of the gear it lifts up the nib off the paper. It makes these perfectly consistent even dotted lines.