Machining Marks For maximum fatigue life，all bored and drilled holes should have a smooth finish, without any machining witness marks showing. Special drills are available that impart a smoother finish than a twist drill where this is nec…

ECONOMIC CONSIDERATIONS In order to evaluate the extent of an installation with which to proceed, the following points should be considered: an analysis of the plastic molding products currently being produced, the markets, the present cos…