(A) disconnection problem: 1. Machine needle with a blunt, leading to the deformation of the needle bar. (Needle exchange, beginners should use the needle on the 14th, its strength, toughness on the 9th, the 12th Needle durable) 2. Reverse. (Beginners should learn to control the last round to control the reversal by hand, so as not hung up, empty step machine) (b) card line problems. Dirt. (Push the needle plate, remove the spindle sleeve spindle bed, bobbin, wipe with cotton cloth, and then a thick duck feathers brushing feed the teeth in the dirt, oil drops on the run). Nose clamp, spring is too tight or too loose. (Adjust the tightness of the spring to make it smooth, natural pull). Shuttle to put the screws too tight or too loose. (The method is very simple adjustment screw) 4. Card line, there are two methods of prevention, a surface line of the bottom line thickness to be consistent. Second, in accordance with the provisions of the order of threading can not be wearing the wrong. (C) of the vibration problem. Machine to put a smooth installation machine screw must be tighten firmly board screws to twist a bit deeper to the exposed surface. (2) when using the machine, the person's weight should not all the pressure on the board in Taiwan, to prevent the plate deformation. (D) the maintenance of household sewing machines. When the sewing machine is idle, the presser foot pads put a layer of cloth, machine head should cover the pieces of cloth to prevent dust, moisture, sun.Two. Raise the presser foot when sewing thick (half-lift), or it may result in broken needles break.3. Remove the nose section of dirt, do not use toothpicks, needles and other sharp objects to avoid damage to parts.4. Belt with a long widening the more loose, the machine will not go away - go on, you can spare a homemade belt, solid and durable. The belt method of making the waste material pants cut an inch wide strips of cloth wrapped around a rope on the pin connections, the length of the original belt length equal to a good system hang, you can use.