Abstract: The apparatus includes a rotatable headstock trimmer unit including a reciprocating spindle that is rotatable about a horizontal axis and has an annular cutting element secured to one end thereof for engaging the open upper end of an outwardly flanged can, a rotatable tailstock unit including a can base holder that is rotatable about an axis coaxial with the horizontal axis of the trimmer unit and which engages the lower end of the flanged can, and a rotatable cutting element disposed in the path of the reciprocating annular cutting element. The spindle and can base holder rotate about the same horizontal axis, the spindle reciprocates to engage the annular and rotatable cutting elements which cooperate to trim outwardly flanged end portion at the open end of the can.