The cause of the malfunction: knife too far forward when the computer tricks machine operation to a low-speed zone, the knife slightly forward move that this timing pin down just run into the knife, causing the "bald" tip. Remedy: we can release the knife rod fastening screws, and then move backward a little in the locking screw can be. The cause of the malfunction: the position of the presser foot standard computer tricks machine presser foot mounted front or back, will make the machine needle hits the presser foot and damage to the point of a needle. Remedy: re presser foot is properly installed, allowing the machine to turn off the power longitudinal feed, and then rotate the pulley by hand to see whether the needle and the presser foot friction. Subsequently, we release the pressure fixed tripod screw, move forward or backward pressure tripod, then locking screw. The cause of the failure: premature stopping time if the parking time prematurely on the then the the computer tricks shear line rocker back the ball prematurely falling from the driver board cut line rod forward and promote the knife, so that moving the knife forward moving a little, when the operation of the machine to the last few needles encounter knife and broke the tip Remedy: We can lift and lock the nose, with the allen wrench to loosen the three screws on the broader market, gently the brake variable speed cam clockwise rotation a little, tighten the screws. Then we turn on the power, hold down the pedal rotation to turn off the power towards the end of the computer tricks machine. Finally, we turn the pulley by hand to see whether the parking block stop the parking cam a screw. If the parking is not accurate, we have to repeatedly adjust the three screws on the broader market. Need to pay attention, be sure to stop at this location, parking will prematurely damage the needle tip, the parking too late to affect the shear line, sometimes helpless line Parking sound great.