Abstract: A method of controlling chatter in a rotating, chip cutting machine tool cutting at a predetermined depth on a workpiece in which the speed of rotation of the cutting tool relative to the workpiece and the rate of speed of the cutting tool relative to the workpiece both adjustably controlled between predetermined minimum and maximum rates for the particular combination of machine tool and workpiece material. The method includes the steps of detecting vibration signals representative of relative vibrations between the machine tool and the workpiece and generated by preliminary operation of the machine tool at predetermined conditions, processing that generated signal as a function of signal frequency, obtaining a signal indicative of the rotational speed and determinating the threshold of the signal level above which are excluded harmonics of the predetermined rotational frequencies that are indicative of chatter in the cutting tool.

Abstract: A closure for a liquid or a semi-liquid fuel can having an ignitable wick is provided. The wick is mounted to the can closure with a coil spring structure so that the wick can be depressed and extended relative to the upper surface of the can closure. A recessed portion is defined in the upper surface of the canned closure for receiving the wick in its depressed condition and the compressed wick is retained therewithin with a peelable seal. Removal of the peelable seal allows the wick and coil stem assembly to extend to an operating position wherein the wick can be easily ignited.

Abstract: A cooking fuel can closure is provided wherein at least one aperture is defined through the upper surface of the can and a peelable seal such as a thin metal foil is secured by, for example, adhesive to the upper surface of the can peripherally of the opening through the can. Further, a plurality of peripheral openings can be defined about a central aperture in the can so as to facilitate flow of oxygen to the burning fuel thereby using less fuel while still obtaining the same or better burn efficiency of the cooking fuel. Finally, a wick element can be provided centrally of the cooking can closure in a concave portion which is peripherally sealed prior to use by a peelable seal so as to prevent leakage therethrough.