V-Block

A V-block is a simple jig -- a block of wood or metal with a V-shaped groove cut along its length -- that cradles round stock (a dowel, a rod, a turned spindle) securely for drilling, marking, or cutting, something a flat surface alone can't do since round stock simply rolls on a flat table. Drilling a hole dead-center through the end of a dowel, for instance, is genuinely difficult freehand on a flat surface but straightforward with the dowel nestled and held steady in a matched V-block under the drill press.