StainTrac Stain Systems offers a line of stain machines to quickly and efficiently stain fence pickets, posts, and other wood products. StainTrac provides a revolutionary new way to pre-stain – pickets, posts, rails, cap boards and more – up to 4″ wide and 8″ deep. Each board is sprayed with stain, then passes through nap rollers to remove excess and evenly spread stain to all surfaces. Excess stain drains back into the bucket below and is re-circulated… so there’s virtually zero waste.