Pfaff 571 Guide

571
574
296-12-19 305/002
Adjustment Manual engl. 08.15
This adjustment manual applies to machines
from the serial number 7260 186 and
adjustment manual 0435/002 onwards.
ADJUSTMENT MANUAL
591

Reprinting, reproduction and/or translation of PFAFF adjustment manuals (including
parts thereof) is only permitted with our prior agreement and citation of the source.
PFAFF Industriesysteme und Maschinen GmbH
Hans-Geiger-Str. 12 - IG Nord
D-67661 Kaiserslautern
Germany

Table of Contents
Contents ..................................................................................Page
3
13 Adjustment ........................................................................................................................... 5
13.01 Tools, gauges and other accessories ................................................................................ 5
13.02 Abbreviations ....................................................................................................................... 5
13.03 Explanation of symbols....................................................................................................... 5
13.04 Adjusting the basic machine............................................................................................... 6
13.04.01 Needle position in sewing direction (on the PFAFF 571 and 591) ......................................... 6
13.04.02 Needle position in sewing direction (on the PFAFF 574)........................................................ 7
13.04.03 Needle height (pre-calibrating) ............................................................................................... 8
13.04.04 Hook-to-needle clearance, needle bar rise, needle height and needle guard
(on the PFAFF 571) ................................................................................................................ 9
13.04.05 Hook-to-needle clearance, needle bar rise, needle height and needle guard
(on the PFAFF 574) ............................................................................................................... 10
13.04.06 Hook-to-needle clearance, needle bar rise, needle height and needle guard
(on the PFAFF 591) .............................................................................................................. 12
13.04.07 Needle position crossways to sewing direction (on the PFAFF 571) ................................... 13
13.04.08 Needle position crossways to sewing direction (on the PFAFF 574).................................... 14
13.04.09 Needle position crossways to sewing direction (on the PFAFF 591) ................................... 15
13.04.10 Bobbin case opener height and bobbin case opener travel ................................................. 16
13.04.11 Feed wheel height (on the PFAFF 571)................................................................................ 17
13.04.12 Feed wheel height (on the PFAFF 574) ................................................................................ 18
13.04.13 Feed wheel height (on the PFAFF 591)................................................................................ 19
13.04.14 Reverse-feed lever eccentric................................................................................................ 20
13.04.15 Stitch length scale dial ......................................................................................................... 21
13.04.16 Shaft crank for feed wheel drive .......................................................................................... 22
13.04.17 Shaft crank for roller presser drive....................................................................................... 23
13.04.18 Clearance between roller presser and feed wheel .............................................................. 24
13.04.19 Roller presser....................................................................................................................... 25
13.04.20 Stitch length to stitch length scale....................................................................................... 26
13.04.21 Synchronisation of roller presser and feed wheel................................................................ 27
13.04.22 Press pad (only on the PFAFF 574)....................................................................................... 28
13.04.23 Knee lever ............................................................................................................................ 29
13.04.24 Release needle thread tension ............................................................................................ 30
13.04.25 Thread check spring (on the PFAFF 571 and 591)................................................................ 31
13.04.26 Thread check spring (on the PFAFF 574) .............................................................................. 32

Table of Contents
Contents ..................................................................................Page
4
13.04.27 Bobbin winder...................................................................................................................... 33
13.04.28 Roller presser pressure........................................................................................................ 34
13.04.29 Lubrication ........................................................................................................................... 35
13.04.30 Re-engage safety clutch....................................................................................................... 36
13.05 Adjust edge trimmer -725/04 ............................................................................................ 37
13.05.01 Knife carrier position (on the PFAFF 571)............................................................................. 37
13.05.02 Knife carrier position (on the PFAFF 591)............................................................................. 38
13.05.03 Knife stroke (on the PFAFF 571) .......................................................................................... 39
13.05.04 Knife stroke (on the PFAFF 591) .......................................................................................... 40
13.05.05 Knife movement (on the PFAFF 571) ................................................................................... 41
13.05.06 Knife movement (on the PFAFF 591) ................................................................................... 42
13.05.07 Knife position ....................................................................................................................... 43
13.06 Adjust thread trimmer -900/83 .......................................................................................... 44
13.06.01 Roller lever neutral position / control cam radial position..................................................... 44
13.06.02 Thread catcher carrier position............................................................................................. 45
13.06.03 Thread catcher position........................................................................................................ 46
13.06.04 Knife position and knife pressure......................................................................................... 47
13.06.05 Bobbin thread clamp spring ................................................................................................. 48
13.06.06 Manual test cut.................................................................................................................... 49
13.06.07 Tension release .................................................................................................................... 50
13.06.08 Linkage rod (only on the PFAFF 574).................................................................................... 51
13.07 Adjust backtacking mechanism -911/............................................................................... 52
13.07.01 Needle in needle hole (on the PFAFF 571 and 591)............................................................. 52
13.07.02 Clutch for roller presser drive............................................................................................... 53
13.07.03 Adjust roller presser drive .................................................................................................... 54
13.07.04 Bevel gears for feed crank drive........................................................................................... 55
13.07.05 Adjust switching magnet for feed crank drive...................................................................... 56
13.07.06 Adjust switching magnet for feed crank drive (on-725/04)................................................... 57
13.06 Parameter settings ............................................................................................................ 58
13.07 Internet update of control P40 CD ................................................................................... 58
14 Circuit Diagrams 91-191 581-95 ....................................................................................... 59

Adjustment
5
13 Adjustment
Observe and comply with all instructions in the operating manual's chapter
1Safety! In particular make sure that all safety covers are installed again
correctly after making adjustments, see chapter 1.06 Operating manual
hazard information!
Unless otherwise stated, the machine must be disconnected from the electric
supplies before all adjustment work!
Risk of injury due to accidental machine start-up!
Notes on adjustment
All adjustments in this manual are based on a fully assembled machine and may only be
carried out by technical staff trained for this purpose. Machine covers, which have to be
removed and replaced to carry out checks and adjustments, are not mentioned in the text.
The order of the following chapters corresponds to the most logical work sequence for
machines that have to be completed adjusted. Both the preceding and following chapters
must be observed if only specific individual work steps are carried out. Screws and nuts
indicated in brackets () are fastenings for machine parts, which must be loosened before any
adjustment and tightened again afterwards.
13.01 Tools, gauges and other accessories
1set of screwdrivers with blade widths from 2to 10 mm
1set of wrenches with jaw widths from 7to 13 mm
1set of Allen keys from 1.5to 6mm
1metal ruler (order no. 08-880 218-00)
Needle rise gauge (order no. 61-111 600-01
Screw clamp (order no. 61-111 600-35))
13.02 Abbreviations
TDC = top dead centre
BDC = bottom dead centre
13.03 Explanation of symbols
Activities to be performed or important information in this adjustment manual are
emphasised by symbols. The symbols used have the following meaning:
Note, information
Maintenance, repairs, adjustment, service work
(only to be carried out by technical staff)

Adjustment
6
Fig. 13 - 01
13.04 Adjusting the basic machine
13.04.01 Needle position in sewing direction (on the PFAFF 571 and 591)
Set the minimum stitch length.
Adjust the needle bar (screw 1) according to the rule.
Rule
The needle should be at the centre of the stitch hole looking in the sewing direction with
minimum stitch length regulation.
1

Adjustment
7
13.04.02 Needle position in sewing direction (on the PFAFF 574)
Rule
The needles should be at the centre of the stitch hole looking in the sewing direction.
Adjust the needle bar frame (screws 1and 2) according to the rule.
Fig. 13 - 02
22
1

Adjustment
8
13.04.03 Needle height (pre-calibrating)
Rule
At TDC there should be a clearance of approx. 21 mm between the needle bar and the
needle plate.
Adjust the needle bar 1(screw 2) without twisting according to the rule.
Fig. 13 - 03
2
1
21 mm

Adjustment
9
13.04.04 Hook-to-needle clearance, needle bar rise, needle height and needle guard
(on the PFAFF 571)
Rule
With the needle rise positioned 2.4mm after BDC of the needle bar and with stitch
length regulation "0"
1. the hook point should be at the needle midpoint, and should be at a distance of 0.05
to 0.1mm to the needle,
2. the upper edge of the eye of the needle should be 0.8to 1.0mm under the tip of the hook.
3. the needle guard 5should lightly touch the needle.
Set the stitch length to "0".
Loosen all of the screws 1, 2, 3and 4.
Adjust the needle bar positioned 2.4mm after BDC.
Set the hook point on the middle of the needle and take care that the needle is not
squeezed by the needle guard 5.
Adjust the needle height according to rule 2.
Adjust the hook post according to rule 1and tighten the screws 4and 2.
Tighten the screws 1allowing for bevel gear wheel movement.
Adjust the retaining collar 6up against the bevel gear 7and tighten the screws 3.
Adjust the needle guard 5(screw 8) according to rule 3.
When changing a hook take care that the markings 9and 10 are on one side.
Fig. 13 - 04
4
0.8 - 1 mm
5
85
231
67
9
10

Adjustment
10
Loosen the screws 1, 2, 3, 4, 5, 6and 7.
Slightly loosen the screws 8.
Adjust the needle bar positioned 2.4mm after BDC.
Set both hook points on the middle of the needle and take care that the needles are not
squeezed by the needle guard 9.
Adjust the needle height according to rule 2.
13.04.05 Hook-to-needle clearance, needle bar rise, needle height and needle guard
(on the PFAFF 574)
Rule
On both hooks with the needle rise positioned 2.4mm after BDC of the needle bar,
1. the hook point should be at the needle midpoint, and should be at a distance of 0.05
to 0.1mm to the needle,
2. the upper edge of the eye of the needle should be 0.8to 1.0mm under the tip of the
hook.
3. the needle guard 9should lightly touch the needle.
Fig. 13 - 05
7
8
8
3
456
12
12
10 11 13
77
7
8
9
14
0.8 - 1 mm
9
15
16

Adjustment
11
Adjust both hook posts according to rule 1and tighten the screws 8.
Tighten the screws 1and 6.
Tighten the screws 3and 5allowing for bevel gear wheel movement.
Adjust the retaining collar 10 up against the bevel gear 11 and tighten the screws 2.
Adjust the retaining collar 12 up against the bevel gear 13 and tighten the screws 4.
Tighten the screws 7on both sides of the post.
Adjust the needle guard 9(screw 14) on both hooks according to rule 3.
When changing a hook take care that the markings 15 and 16 are on one side.

Adjustment
12
13.04.06 Hook-to-needle clearance, needle bar rise, needle height and needle guard
(on the PFAFF 591)
Rule
With the needle rise positioned 2.4mm after BDC of the needle bar and with stitch
length regulation "0"
1. the hook point should be at the needle midpoint, and should be at a distance of 0.05
to 0.1mm to the needle,
2. the upper edge of the eye of the needle should be 0.8to 1.0mm under the tip of the hook.
3. the needle guard 6should lightly touch the needle.
Fig. 13 - 06
6
9
4
5
5
1
4
3
78
2
Set the stitch length to "0".
Loosen the screws 1, 2, 3, 4and 5.
Adjust the needle bar positioned 2.4mm after BDC.
Set the hook point on the middle of the needle and take care that the needle is not
squeezed by the needle guard 6.
Adjust the needle height according to rule 2.
Adjust the hook post according to rule 1and tighten the screws 4and 3.
Tighten the screws 2allowing for bevel gear wheel movement.
Adjust the retaining collar 7up against the bevel gear 8and tighten the screws 1.
The screws 5remain loosened for further adjustments.
Adjust the needle guard 6(screw 9) according to rule 3.
When changing a hook take care that the markings 10 and 11 are on one side.
0.8 - 1 mm
10
11

Adjustment
13
13.04.07 Needle position crossways to sewing direction (on the PFAFF 571)
Rule
The needle should be at the centre of the stitch hole when entering and exiting the
needle plate with maximum stitch length regulation.
Adjust the screws 1(screws 2, on both sides of the post) according to the rule.
Fig. 13 - 07
2
2
2
2
1

Adjustment
14
13.04.08 Needle position crossways to sewing direction (on the PFAFF 574)
Adjust the mounting plate 1(screws 2, on both sides of the post) according to the rule.
Rule
The needles should pierce the middle of their stitch holes looking crossways to the
sewing direction.
Fig. 13 - 08
1
2
2
2
2

Adjustment
15
13.04.09 Needle position crossways to sewing direction (on the PFAFF 591)
Rule
The needle should pierce the middle of the stitch hole looking crossways to the sewing
direction.
Adjust the feed wheel post 1(screws 2, 3and 4) according to the rule.
Fig. 13 - 09
3
1
2
4
4
4
2

Adjustment
16
13.04.10 Bobbin case opener height and bobbin case opener travel
Rule
1. The upper edges of the bobbin case opener 1 and bobbin case base 3 should be at the
same level.
2. When the bobbin case opener 1 has deflected the bobbin case to its furthest point,
the catch of the bobbin case should be approx. 0.3 - 0.5 mm from the back edge of
the needle plate recess.
Adjust the bobbin case opener 1(screw 2) according to rule 1.
Turn the handwheel until the bobbin case opener has deflected the bobbin case to its
furthest point.
Turn the bobbin case opener 1(screw 2) according to rule 2.
The settings should be repeated on the right post on the PFAFF 574.
The setting may differ from rule 2depending on the thread thickness.
1
2
Fig. 13 - 10
3
1
0,3 - 0,5 mm

Adjustment
17
13.04.11 Feed wheel height (on the PFAFF 571)
Rule
1. The feed wheel 4 to which pressure is applied should protrude out of the needle plate
by the tooth height (approx. 0.8 mm).
2. The feed wheel 4to which no pressure is applied should have approx. 0.3mm height
clearance.
Swivel out the roller presser.
Loosen the screws 1and 2.
Adjust the drive wheel 3according to rule 1; take care that the toothing of the drive
wheel 3and feed wheel 4interlock properly.
Tighten the screws 1.
Adjust the guide 5according to rule 2and tighten the screws 2.
Fig. 13 - 11
2
1
5
3
4
0.8 mm
0.3 mm
1

Adjustment
18
13.04.12 Feed wheel height (on the PFAFF 574)
Rule
1. When pressure is applied to the feed wheel 4, it should protrude from the needle
plate by the tooth height (approx. 0.8 mm).
2. The feed wheel 4to which no pressure is applied should have approx. 0.3mm height
clearance.
Swivel out the roller presser.
Loosen the screws 1and 2(two screws each).
Adjust the drive wheel 3according to rule 1; take care that the toothing of the drive
wheel 3and feed wheel 4interlock properly.
Tighten the screws 1.
Adjust the guide 5according to rule 2and tighten the screws 2.
Fig. 13 - 12
1
5
3
4
0.8 mm
0.3 mm
1
2

Adjustment
19
13.04.13 Feed wheel height (on the PFAFF 591)
Rule
The feed wheel should protrude out of the needle plate by the tooth height
(approx. 0.8mm).
Swivel out the roller presser.
Loosen the screws 1.
Turn the eccentric 3(retaining screw can be accessed through the hole 2) according to
the rule.
Tighten the screws 1.
Fig. 13 - 13
1
32
0.8 mm

Adjustment
20
13.04.14 Reverse-feed lever eccentric
Rule
If the needle (at the maximum stitch length setting) is 3mm above the needle plate from
the top dead centre position, the crank 3should have reached its front turning point posi-
tion.
Set the maximum stitch length.
Turn the reverse-feed lever 1(screws 2) according to the rule.
1
2
2
Fig. 13 - 14
3