In order to maintain their body temperatures, Chickadees must take in a large number of food calories which will be metabolized for body heat. Calder (1974) notes that Black-capped Chickadees ... must eat continuously during short daylight hours to stoke their metabolic fires.
Industrial sewing machines are the best option for sewing upholstery-grade fabrics such as vinyl and leather because these machines are designed to handle thicker fabrics. Industrial machines use heavier upholstery thread and often sturdier needles which penetrate the material cleanly.
A computer program is customized for an object and the machines are programmed with CNC machining language (called G-code) that essentially controls all features like feed rate, coordination, location and speeds. With CNC machining, the computer can control exact positioning and velocity. CNC machining is used in manufacturing both metal and plastic parts. First a CAD drawing is created (either 2D or 3D), and then a code is created that the CNC machine will understand. The program is loaded and finally an operator runs a test of the program to ensure there are no problems.