The special structure of the cantilever cylinder is particularly suitable for the lap joint of the sleeve, the trousers and the like. After thorough improvement of the sewing seam, the sewing machine has realized the low tension of the thread and the bottom line. Through the line adjustment mechanism and the curved needle and other positioning components of the substantial improvement, eliminating the wrinkles to get beautiful stitches. Easy to operate the shape of the body, a simple button-type feed volume conversion, to increase the adaptability when the material, send cloth stability. Applicable to men’s, women’s, shirts, overalls, casual pants, raincoats and other sewing.