If you want to know how to maintain the scraper of a screen printing machine and some maintenance techniques, you must first know how to operate the scraper normally and some common techniques for operating the scraper. Only the correct and methodical operation of the scraper can reduce the loss of the scraper.
Generally speaking, there are three ways to operate the screen printing scraper:
(1) Scrape the ink on the side close to you, push the end of the scraper to scrape the ink back;
(2) Between 70° and 50°, scrape to the side close to you, between 110° and 120°, when the ink returns, scrape to the front;
(3) Contrary to the operation method of (1), advance the scraper to print, and move in the opposite direction when returning to the ink.
These three printing methods have their own characteristics, such as the viscosity of the ink and the shape of the substrate surface, and each has its own advantages and disadvantages. Simply put, when using the above three operation methods to operate the scraper, you must pay attention to the following operation details: a. When scraping, you must ensure that the scraping angle is not too large or too small, otherwise it will directly cause the scraper to wear; b. pressure. If it is manual printing, the operator needs to use his arm to adjust the imprinting force, if it is mechanical printing, he needs to adjust the bolt to adjust the imprinting force. However, whether it is manual or mechanical, many experiments must be done to check the effect of screen printing.
At the same time, it is necessary to check the sscraper thoroughly before starting printing. When starting, first check whether the blade of the scraper is straight and without teeth. After printing, use a cotton swab dipped in a suitable amount of solvent to scrape off the remaining ink on the tape. Never use an ink knife to directly scrape off the residual ink on the tape. If the scraper needs to be stored for a long time, the solvent on its surface should be volatilized, and then sealed and stored.
Even if the screen printing scraper is operated correctly, the scraper will still wear out after a period of use, so it is necessary to grind the scraper at this time. Similarly, grinding can be divided into manual grinding and mechanical grinding. At the same time, pay attention to rough grinding before fine grinding. The manual sanding repair scraper is to stick the sandpaper on a straight wood or glass plate, hold both ends of the scraper with both hands, so that it is perpendicular to the sandpaper, push and pull on the sandpaper in one direction, requiring a stable force, and keep it vertical when pushing and pulling, and do not swing. The speed should be moderate. Remember not to polish with the emery cloth in your hand. When the scraper is used for mechanical grinding, fix the scraper vertically on the grinding scraper and grind gently. Don't use too much force to avoid twists and turns. During the grinding process, the rubber in the grinding part of the scraper sometimes becomes sticky due to heat. This can be prevented by coating some talcum powder on the grinding part.