Semi-automatic mechanism designed to perform initial de-boning processes. The machine has a special device which enables the user to adjust the amount of leg to be removed with or without the trotter. This automatic cutting operation, with its protective guard, is carried out once the ham has been held in position using a disc blade with hard metal inserts This makes it possible to reduce processing times, while simultaneously carrying out other operations such as gouging, cutting, etc. safely thereby removing the need for additional stages.