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, locksmiths are still the basic technology widely used in the process of mechanical manufacturing, although most of their work has been gradually mechanized and automated. The reason for this is the following：
Up to now, there is no suitable mechanized equipment to replace 1, marking, scraping, grinding, mechanical assembly and other locksmith work;
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 small batch production, maintenance or lack of equipment.
Main tasks of locksmith
Machining 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. 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.
1, archive
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 trim 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
Commonly used materials for file are carbon tool steels T 12, T 12A and T 13A, and the hardness after quenching can reach above 62HRC.
3, the structure and the name of each part
(1) File body: the part between the file tip and the file shoulder is the file body. For plastic files without shoulders, the file body refers to the part with file lines.
(2) Gear handle: the part outside the gear body.
(3) Parallel parts of the file body: the parts where the bus bars of the file body are parallel to each other are parallel parts of the file body.
(4) Tip: between the starting point and the tip, the cross-sectional size of the file body begins to decrease gradually. (File body length = tip length+file body parallel part)
(5) Main file pattern: The file pattern that plays the main cutting role on the file working face is the main file pattern.
(6) Auxiliary file mode: the file mode covered by the main file mode is the auxiliary file mode.
(7) Edge file marks: the narrow edge of the file or the file marks on the narrow edge are edge file marks.
(8) Oblique angle λ (ω) of the main (auxiliary) file: the acute angle formed by the main (auxiliary) file and the axis of the file body is the oblique angle λ (ω) of the main (auxiliary) file.
(9) Oblique angle θ of the edge file: the acute angle formed by the edge file and the axis of the file body is the angle θ of the edge file.
(10) Number of file lines: the number of file lines per 10mm in the axial direction of the file is the number of file lines.
(1 1) File bottom line: On the vertical section perpendicular to the main file pattern, the straight line passing through two adjacent tooth bottoms is the tooth bottom connecting line.
(12) Tooth height: the distance from the tooth top to the tooth bottom line is the tooth height.
(13) Tooth rake angle: On the normal surface of the main file passing through the tooth tip, the acute angle formed by the intersection of the cutting edge surface and the normal surface of the file with respect to the vertical line connecting the tooth bottom is the tooth rake angle.
4. Types
(1) The locksmith file (common file) can be divided into flat file, semi-circular file, triangular file, square file and round file according to the different cross-sectional shapes of the file body.
(2) Special-shaped files are used when processing special surfaces, including diamond files, single-sided triangular files, knife files, double semi-circular files, oval files, round belly files, etc.
(3) The forming file is used to trim small parts on the workpiece.
5. How to use it
(1) Use one side first for new gears, and then use the other side when it is dull.
(2) When rough filing, the effective full length of the file should be fully utilized, which can not only improve the file efficiency, but also avoid the local wear of the file teeth.
(3) Don't touch oil and water on the file.
(4) When filing, if the file chips are embedded in the tooth gaps, it is necessary to use a wire brush or a thin iron sheet or a copper sheet in time to remove the chips on the file teeth along the direction of the file teeth.
(5) It is not allowed to file the hard skin of the blank and hardened workpiece, and file soft metals such as aluminum and tin. Single-tooth files should be used.
(6) If there is crust or sand on the casting surface, it should be ground off with a grinding wheel first, or leveled with a semi-pointed file or an old file, and then processed.
(7) Don't touch the plane of the file by hand when filing, so as to avoid slipping when filing again.
(8) The file must be cleaned after use to avoid rusting.
(9) Don't pile up with other tools or workpieces, and don't overlap with other files, so as not to damage the file teeth.
Use of documents
6. Security matters
(1) The file is a right-handed tool and should be placed on the right side of the vise. When placed on the vise table, the handle of the file should not be exposed outside the vise table, so as to avoid touching the ground and hurting feet or damaging the file.
(2) Files with useless handles or files with cracked handles cannot be used.
(3) When filing, the file handle should not touch the workpiece, so as to avoid the accident caused by the file handle falling off.
(4) Don't blow the filings with your mouth, and don't rub the filing surface with your hands.
(5) The file shall not be used as a crowbar or hammer.
7. Maintenance
(1) In order to prevent the file from wearing too fast, do not file the hard skin of the blank or the hardened surface of the workpiece with a file, but use other tools or the front end and side teeth of the stand first.
(2) When filing, use one side of the falling knife first, and then use the other side after this side is dull. Because used file teeth rust easily.
(3) When filing, make full use of the effective working face of the file to avoid local wear.
(4) The file cannot be used as a tool for disassembly, knocking and prying, so as to avoid the file being broken due to fragile materials.
(5) When using plastic files and small files, do not use too much force to prevent the knife from breaking.
(6) The file should be waterproof and oil-proof. Files rust easily when they are wet with water. The file is easy to slip when working after being stained with oil.
(7) In the process of filing, if chips are found embedded in the file lines, they should be removed in time to avoid the chips scratching the machined surface. After the file is used up, brush off the remaining debris along the file line with a file brush or copper sheet to prevent rust. Never blow potato chips with your mouth to prevent them from flying into your eyes.
(8) When placing files, avoid collision with hard objects, avoid file overlapping and stacking, and prevent file damage.