The fitter's operations mainly include chiseling, filing, sawing, marking, drilling, reaming, tapping and tapping (see thread processing), scraping, grinding, correcting, bending and riveting. Fiddler is the oldest metalworking technology in mechanical manufacturing. /kloc-after the 0/9th century, with the development and popularization of various machine tools, although most locksmith operations have been gradually mechanized and automated, locksmith is still the basic technology widely used in the process of mechanical manufacturing. The reasons are as follows: ① fitter operations such as marking, scraping, grinding and mechanical assembly have not been completely replaced by suitable mechanized equipment; (2) Some of the most sophisticated templates, molds, measuring tools and mating surfaces (such as guide surfaces and bearing shells). ) still need to rely on the skills of workers for precision machining; (3) It is still an economical and practical method to manufacture some parts by locksmith in the case of single piece and small batch production, repair or lack of equipment. The main task of editing this paragraph is to machine parts: some machining that is not suitable or can't be solved by mechanical methods can be done by fitters. Such as: scribing in the process of machining parts, precision machining (such as scraping templates, making molds, etc. ), inspection and maintenance, etc. Bench assembly: according to the assembly technical requirements of mechanical equipment, the parts are assembled, and after adjustment, inspection and debugging, they become qualified mechanical equipment. Equipment maintenance: If the machinery fails, is damaged or its accuracy drops after long-term use, it should also be maintained by locksmith. Tool manufacturing and repair: manufacturing and repairing all kinds of tools, fixtures, measuring tools, molds and various professional equipment. Archive 1. In the locksmith's operation, the file occupies a large proportion, so it can be said that the manufacture of every workpiece is inseparable from the file. Archiving has a wide range of processing. It can process all kinds of complicated inner and outer planes, inner and outer curved surfaces, inner and outer angles, grooves and curved surfaces. Despite the rapid development of modern technology, filing is still used to rest and repair a single part in the assembly process, to process some parts with complex shapes under the condition of small batch production in the assembly process, and to make molds. Thus, archiving still occupies a very important position in modern industrial production. There are many fine teeth and strips on the surface, which is a hand tool for filing workpieces. Used for the micro-machining of metal, wood, leather and other surface layers. Files were used very early, and the oldest file found was a bronze file made in Egypt around BC 1500. Modern files are generally made of carbon steel through rolling, forging, annealing, grinding, tooth cutting and quenching. 2. Materials