Log splitters are machines that split firewood logs into smaller pieces using hydraulic pressure, kinetic energy, or mechanical leverage. Splitting wood with a maul and wedge is labor-intensive at volumes exceeding 2 to 3 cords per year, making powered log splitters a practical investment for homesteads that heat with wood. A cord of wood is 128 cubic feet (3.6 cubic meters) stacked and typically requires splitting 150 to 300 logs depending on log diameter. [[Chainsaw Maintenance]] covers the cutting equipment needed to process felled trees into splitter-length rounds.
Hydraulic log splitters use a hydraulic cylinder driven by a gasoline engine or electric motor to push the log against a stationary wedge. Splitting force ranges from 5 to 35 tons, with 20 to 25 tons being suitable for most homestead needs. Cycle time, the time for the ram to extend and retract, ranges from 10 to 20 seconds. Horizontal splitters allow the operator to work from a standing position and are the most common design. Vertical splitters allow positioning of large, heavy rounds without lifting and are preferred for processing large-diameter wood.
Kinetic log splitters, also called flywheel or ram splitters, store energy in a spinning flywheel and release it rapidly to drive the log through the wedge. They are faster than hydraulic splitters, with cycle times of 2 to 4 seconds, but require careful triggering and are not suitable for knotty or stringy wood. Manual splitters use a lever mechanism or screw action to generate splitting force without an engine. They process 1 to 2 cords per day with moderate physical effort. The traditional splitting maul, a wedge-shaped hammer weighing 3 to 4 kilograms (6 to 8 pounds), remains the simplest splitting tool for small volumes.
Hydraulic splitter operation requires keeping hands clear of the wedge and ram at all times. Two-hand controls, requiring both hands to operate the control levers, are standard on modern splitters. Kinetic splitters present a higher risk of injury because the fast ram cycle can catch loose clothing or gloves. Safety glasses, steel-toed boots, and hearing protection are required for all powered splitter operation. Log splitters should never be operated by a single person if the operator must hold the log in place while reaching for the control lever.