Three-side trimmer, especially for short runs

A trimmer including a common support frame and first and second cutting units movably mounted on the common support frame. Each respective cutting unit including a unit frame, a cutting strip connected to each respective unit frame, and a knife movably mounted on each respective unit frame for an oblique swing cut against a respective cutting strip. Each respective unit frame absorbing all cutting forces between the knife and the cutting strip during the oblique swing cut.