In this discipline, the competitor uses a customised chain saw with a modified engine, usually taken from a personal watercraft or snowmobile.
At the signal, the competitor starts the saw and makes three cuts. With only six inches of wood to work with, precision is key. If the competitor saws outside of the designated six inches or fails to saw a complete "cookie" (term used to describe the circular piece of sawed-off wood), he will be disqualified.
Often described by competitors as both a favourite and the most difficult discipline, the primary challenge with the hot saw is the reliability of the custom saw. U.S. competitor Matt Bush set the world record in the hot saw at 5.085 seconds in 2003.