Sawdust is a byproduct material obtained by processing Wood (logs) or Wooden Planks through the Precision Sawmill. From Wood, you will always receive Sawdust as a byproduct, while Wooden Planks have a 25% chance to yield Sawdust.
As of Mekanism 8 (Minecraft 1.7.10), it is primarily used to create Paper.
Uses in Crafting
Paper (Yields 2)