DURKOPP ADLER 512-211-01, Service Instructions Manual

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Adjusting the hook and needle bar
Service Instructions 512-211-01/532-211-01 - 00.0 - 06/2016 25
5.2 Adjusting the loop stroke and needle guard
Loop stroke
The loop stroke is the path length from the lower dead center of the need-
le bar to the position where the hook is in the loop stroke position.
Fig. 17: Loop stroke
Checking the correct setting
When the machine is in the loop stroke position, the hook tip should be
located exactly on the center line
of the needle. The needle must be
aligned so that the surface of the groove is parallel to the running direction
of the hook tip. The hook tip should be located in the lower third of the
groove.
Faults caused by an incorrect setting
• Damage to the hook
• Damage to the needle
• Missing stitches
• Thread breakage
Order
Prerequisite:
• A straight and undamaged needle must be inserted (

Operating
manual, Section 4.7 Changing needles ).
WARNING
Risk of injury from sharp and moving parts!
Crushing hazard and puncturing injuries due to
moving and sharp parts.
Switch off the sewing machine before adjusting the
loop stroke and needle guard.
(1) - Center line of the needle
(2) - Hook tip
(3) - Groove
①
②
③