JUKI DDL-9000A, Engineer'S Manual

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1. Puckering 1-1) The needle is too thick. Use a thread as thin as possible. For example, KN and SF
needles are effective.
1-2) Thread tension (top or bottom) is 2-A) The thread path is not smooth. Finish the thread path appropriately.
too high.
2-B) The timing of the hook is too late. Hasten the timing of the hook without occurrence of stitch
skipping to obtain smooth unthreading.
2-C) The feed timing is too fast. Delay the feed timing compared to the needle timing to reduce
feeding.
2-D) The stroke of the thread take- Move the arm thread guide rightward to reduce the thread
up lever is too long. feeding with the thread take-up lever.
2-E) The stroke of the thread take- Increase the stroke.
up spring is too short.
2-F) The thread is made of Nonsmooth Use silicon.
material.
1-3) Pressing is inappropriate. 3-A) The pressure is too high. Minimize the pressure. For some materials, sewing with the
presser slightly floated with the adjustable screw of the minute
presser lifter is effective.
3-B) The finish of the backside of the Use a buff or the like to smooth the presser.
presser is rough.
3-C) The presser is made from Use a fluorine resin presser or a special processed presser.
Nonsmooth material.
1-4) The material is inappropriately 4-A) The needle hole of the throat Replace the current gauge with a new one having a smaller
stretched. plate is too large. diameter hole.
4-B) The thread relief on the backside Use a presser with a smaller thread relief on the backside
of the presser is too large. or without thread relief.
4-C) The parallel level of the presser Replace the presser, or loosen the presser bar holding
is inappropriate. screw and correct the needle entry and presser bend if there
is no needle entry.
4-D) The needle tip is blunt. Replace the needle.
(2) Sewing conditions
Trouble Case (1) Case (2) Check and Corrective measures
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