The scraper, also known as the scribing board, is made of bamboo chips or laminated boards and is a tool for small motors when inserting wires. When inserting wires, use a scraper to separate the insulating paper of the notch, straighten the wires that have been inserted into the slot, and push them to both sides of the slot, so that the embedded wires can easily enter the slot. When making a scraper, the part of the scraping line (the front end and both sides of the front end) should be rounded with a file and polished with sandpaper, so as not to scratch the insulating layer of the wire and the insulating paper at the bottom of the groove when scraping the line. The width is 2cm ~3cm. For castings of certain specific shapes, if the production quantity is small, the shape can be used instead of a piece of wood that is suitable for the cross-sectional shape of the casting to make a scraper. When molding, the scraper moves back and forth along a certain track or around a fixed The central axis rotates to scrape out the required cavity. This kind of molding and core-making method operated by a scraper instead of a shape is called scraper molding. The scraper is easy to make and uses less materials. It is a widely used modeling method. The common ones are rotating scraper molding and guiding scraper molding.
In actual production, whether to adopt the shape of the rotating scraper or the shape of the guide scraper depends on the shape and size of the casting. The short and thick cylinder is shaped with a rotating scraper, and the longer cylinder or other special-shaped bodies with a guide surface are better shaped with a guide scraper. As for the use of scraper molding or real sample molding, it should be decided after comprehensive consideration of various factors such as the production quantity, economy, quality and technical requirements of the casting.
