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The eye of the needle can be facing directly forward or be tilted to the right by a maximum of 20°.
•
Important: Do not tilt the needle so that the needle eye is oriented to the left. This will result in
poor sewing performance (e.g., thread breaks).
•
Note: If the needle will not go into the needle bar without significant force, there may be a burr
in the hole of the needle bar. If that is the case, replace the needle bar.
Thread Clean Thread Path
Thread clean thread path is measured using a length of thread from the machine and a 100 gram weight.
1. Stroke the thread back and forth over the area to be checked for thread clean 50 times. If the
thread breaks or begins to fray prior to the end of 50 strokes, then the area checked is not
“thread clean.” The affected part will require replacement.
2. Only the section of parts where thread will pass over or through is required to meet “thread
clean” standards.
Z-Belt Tension
Z-belt tension is most accurately measured using a BRECO meter. Should a BRECO meter not be available
the z-belt tension needs to be measured as described under Z-Drive Belt Tensioning in this manual.
The specification for z-belt tension is 72-78 Hz (or 6.8±0.3 lbs with the force gauge). The machine must
be set to the Z head-up position and the z-belt tension measurement has to be taken at the midpoint
between the motor pulley and upper z-pulley when using the gauge.
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