The solution to the poor movement of the sewing machine

Clothes go back and forth
When sewing clothes, there is often a phenomenon that the fabric moves back and forth, that is, one step forward and one step back. This is caused by the fact that the feeding teeth are too high, the plane of the teeth exposing the needle plate is too high, and the teeth are always exposed outside the needle plate and reciprocate, causing the fabric to move back and forth. When adjusting, loosen the tooth-lifting crank screw, press down on the tooth with a screwdriver, and lower the feed dog to the standard height, that is, the tooth is exposed to the needle plate by 0.8-1 mm, and then tighten the crank screw.

Clothes do not move forward
The movement of the cloth is entirely transmitted by the teeth. When the fabric doesn't move at all, it's only the teeth that look for faults. If the teeth are too low, it is impossible for the fabric to move forward.

When adjusting, first lift the machine head, loosen the crank screw of the tooth lift, and then gently lift the tooth frame with a screwdriver, so that the feeding tooth is in the direction. It is enough to expose the needle plate by 0.8-1 mm. It is the standard size of the height of the teeth. As long as it is adjusted to this position, the cloth can move normally.

Tighten the screws. When screwing the screw, also pull up the machine head.

Irregular movement of the fabric
In the process of sewing clothes with a sewing machine, sometimes the movement speed of the clothes is uneven, and the stitches are irregular.

The movement of the cloth depends entirely on the cooperation of the feed dog and the presser foot to transport forward. Therefore, when the above irregular movement of the cloth occurs, it can be concluded that the teeth and presser foot are faulty or the pressure is not properly adjusted. For example, the presser foot pressure is too low. If the fabric is not pressed tightly, it will cause irregular movement.

At this time, just turn the pressure adjusting screw down to compress the fabric. The presser foot is too high to hold down the fabric, which will also cause the fabric to move at will, or not move at all. When adjusting, lift the presser foot wrench first, loosen the guide screw, and then move the presser foot rod from top to bottom to make the adjustment. After the distance between the presser foot and the needle plate is adjusted to a height of 7-8 mm, tighten the screw immediately before driving.
Another reason is that due to the loosening of the teeth screws, the teeth are shaken from side to side during operation, so that the cloth cannot move forward regularly.

The solution is to remove the needle plate. Tighten the two tooth screws. After tightening, install the needle plate, check both sides of the teeth, whether there is friction with the edge of the needle plate groove, if there is friction, it will cause noise and machine weight phenomenon, then only remove the needle plate, loosen the tooth screw, Adjust the tooth position to the middle of the slot of the needle plate, and then install the needle plate after tightening the tooth screw.

Clothes go backwards
When sewing work towels, sometimes the fabric does not move forward, but moves toward the operator, that is, the fabric moves backward. This kind of failure is caused by the wrong angle between the upper axle crank and the cam eccentric screw. The teeth can move forward rhythmically. It is completely driven by the feed cam.

Because the cam itself is eccentric. Therefore, the tooth fork is moved back and forth, and the tooth fork drives the cloth feed shaft and the tooth frame, which promotes the reciprocating movement of the teeth back and forth. It can be seen that the eccentric position of the cam is very important.

Standard angle of upper axle crank and cam screw. As long as the angle between the cam screw and the crankshaft of the upper shaft is adjusted to the position of 260-300, the fabric will not retreat.
When adjusting, pull down the back cover of the machine head, you can see the feed cam, insert the screwdriver into the inside of the casing, loosen the screw of the feed cam, and then turn the screw to a 260-300 angle with the crank of the upper shaft. position, and then tighten the cam screw.