Operation; Threading The Needle Thread; Setting The Needle Thread Tension; Releasing The Needle Thread Tension - Dürkopp Adler Class 271 Instruction Manual

6. Operation

6.1 Threading the Needle Thread

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Place the spool of yarn on the yarn stand as shown in the illustration (Page 14).
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Thread the needle thread according to the drawing on the previous page.

6.2 Setting the Needle Thread Tension

Setting of the needle thread pretension
The main tension 4 of the needle thread is open during the thread trimming. For a
secure thread trimming, it is, however, necessary that the needle thread remains
slightly taut during thread trimming. This is achieved through the needle thread
pretension 1. At the same time, the needle thread pretension 1 influences the length of
the cut needle thread end and, thereby, the thread length which is required for the next
secure seam beginning.
Base position:
Shorter beginning thread:
Longer beginning thread:
Note: After greater changes in the needle thread pretension
the main tension 4 may possibly need correction in
order to achieve the same sewing results.
Setting the main tension
The needle thread pretension 1 and main tension 4 together build the thread tension
required for the seam (see Illus. a).
Setting: Turn knurled nut 4 accordingly
Increase tension: Turn knurled nut 4 clockwise
Decrease tension: Turn knurled nut 4 counterclockwise

6.3 Releasing the Needle Thread Tension

Automatic
The main tension 4 is automatically opened during thread trimming.
Caution Risk of Injury !
Turn the main switch off !
Thread the needle thread only with the sewing machine
turned off.
Turn knurled nut 2 until its front lies flush with bolt 3.
Turn knurled nut 2 clockwise
Turn knurled nut 2 counterclockwise.
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