Edward Lyons Irregular Roulette 1/4"x3/16" Barrel EC Lyons roulettes are recognized throughout the printmaking world as the finest roulette's available. A roulette tool has a revolving textured wheel mounted on a shaft with a handle. Roulettes are manufactured with dot patterns, line patterns, or irregular patterns. The number of dots or lines the tool can produce is indicated as dpi or lpi. Roulettes are used on bare copper quickly creating texture that holds ink.