A previously developed palm nut cracking machine was evaluated. The palm nut cracker was evaluated for three major variables affecting palm nut cracking machines. A 3×3×2 factorial design was used for the purpose, which included three levels of cracking drum distance from the rotor (90, 100, 110mm), three palm nut sizes (15, 20, 24mm) and two levels of rotor speeds (1500rpm and 1800rpm). An optimum feed rate of 15kg/h of palm nut as suggested by Babatunde and Okoli (1988) was chosen. The 15mm palm nut sizes indicated maximum machine performance of 92.5% cracking efficiency, 96.1% performance efficiency and 88.7% overall efficiency at 90mm cracking drum distance from the rotor and machine speed of 13m/s. The performance of the machine was found to be influenced by all the studied variables.
