A dispenser for dispensing sheet product is provided. The dispenser includes a housing with an outlet through which sheet product is dispensed. A knife drum is rotatable with respect to the housing. A knife is movable between a retracted position within the knife drum and an extended position where the knife protrudes outside of the knife drum to cut the sheet product. A cam follower surface is fixed with respect to the housing. A cam follower is attached to the knife and operable to engage the cam follower surface and travel therealong to transition the knife between the retracted position and the extended position. A spring assembly biases the knife drum during rotation toward a predetermined position. The spring assembly comprises a first spring and a second spring. The spring assembly is attached at a single mount position that is fixed with respect to the housing.