Fused deposition modeling 3D printer and using method thereof

The invention belongs to the field of 3D printers, particularly relates to a fused deposition modeling 3D printer and a use method thereof, and provides the following scheme aiming at the problems that an existing printer is usually manually operated by a worker, is dangerous, is low in efficiency and cannot work for a long time, and the position of a printing head is inconvenient to adjust: the fused deposition modeling 3D printer comprises a box body and the printing head, a rectangular hole is formed in the top of the box body, a base plate is slidably connected to the inner wall of the box body, and an electric push rod is fixedly connected to the inner wall of the bottom of the box body. 3D printing operation and transverse movement of a scraper can be completed through a printing head, at the moment, the surface of resin can be scraped, and a sponge pad on one side of a mounting plate cleans one side of the scraper; and after the scraper is cleaned, the sliding seat can return to the initial position un