User Guide

Contents
Contents .................................................................................Chapter – Page
12.
05.10 Needle position adjustment lever................................................................................ 12 -12
12.05.11 Zero position of the bottom feed dog (with closed gear box)...................................... 12 -13
12.05.12 Zeroing the bottom feed (with open gearbox) ............................................................. 12 -14
12.05.13 Feeding motion of the bottom feed dog ..................................................................... 12 -15
12.05.14 Lifting motion of the bottom feed dog ........................................................................ 12 -16
12.05.15 Drive belt in the gearbox housing................................................................................ 12 -17
12.05.16 Hook bearing bracket .................................................................................................. 12 -18
12.05.17 Hook lubrication .......................................................................................................... 12 -19
12.05.18 Pre-adjusting the needle height................................................................................... 12 -20
12.05.19 Needle rise, hook-to-needle clearance and bobbin case positioning-finger.................. 12 -21
12.05.20 Final adjustment of the needle height ......................................................................... 12 -22
12.05.21 Bobbin case opener position ....................................................................................... 12 -23
12.05.22 Bobbin case opener motion ........................................................................................ 12 -24
12.05.23 Bottom feed dog height .............................................................................................. 12 -25
12.05.24 Presser foot to needle plate clearance........................................................................ 12 -26
12.05.25 Needle thread tension release (on machines without -900/24).................................... 12 -27
12.05.26 Presser foot pressure ................................................................................................. 12 -28
12.05.27 Thread diverter pin ...................................................................................................... 12-29
12.05.28 Limiting the knee lever stroke..................................................................................... 12 -30
12.05.29 Knee lever play............................................................................................................12-31
12.05.30 Bobbin winder ............................................................................................................. 12 -32
12.06 Adjusting the underedge trimmer -771/04................................................................... 12 -33
12.06.01 Resting position of the knife ....................................................................................... 12 -33
12.06.02 Knife height................................................................................................................. 12 -34
12.06.03 Positioning of the knife ............................................................................................... 12 -35
12.06.04 Knife drive switch ....................................................................................................... 12-36
12.06.05 Workpiece guard......................................................................................................... 12 -37
12.07 Adjusting the thread trimmer -900/24 ......................................................................... 12 -38
12.07.01 Axial position of the control cam ................................................................................. 12 -38
12.07.02 Preliminary adjustment of the control cam ................................................................. 12 -39
12.07.03 Position of the thread catcher and cutting test ........................................................... 12 -40
12.07.04 Readjustment of the control cam................................................................................ 12 -41
12.07.05 Needle thread tension release .................................................................................... 12 -42
12.08 Parameter settings...................................................................................................... 12 -43
12.08.01 Selecting the user level............................................................................................... 12 -43
12.08.02 Example of a parameter input ..................................................................................... 12 -44
12.08.03 List of parameters....................................................................................................... 12-45
12.09 Reset / Cold start ........................................................................................................ 12 -46
12.10 Explanation of the error signals ................................................................................... 12 -47
12.11 Internet update of the machine software.................................................................... 12 -48
13 Wearing parts ............................................................................................................ 13 - 1
14 Circuit diagrams ........................................................................................................ 14 - 1