Minerva Boskovice 1280i User manual

Instruction manual
1280i
Minerva Boskovice, a.s., Sokolská 60, CZ - 680 17 Boskovice
Tel.: [phone], 453433, 494111 Fax: [phone] http://www.minerva-boskovice.com
Edition/Vydáno/Herausgegeben/Edition/Editado: 05/2009Printed/Tisk/Druck/Imprimé/Impress ã o: Czech Republic S735 000616

Contents - part A
1. Proper use of the machine ................................................................................................................................................ 1
2. Description of the machine .............................................................................................................................................................. 1
3. Machine sub-classes and sewing categories .................................................................................................................. 2
3.1 Sub-class ................................................................................................................................................................ 2
3.2 Sewing categories ................................................................................................................................................... 2
4. Survey of equipment ........................................................................................................................................................ 2
4.1 Basic necessary equipment .................................................................................................................................... 2
4.1.1 Needles ...................................................................................................................................................... 2
4.1.2 Wheel feeders .............................................................................................................................................................. 2
4.1.3 Top roller holders ......................................................................................................................................................... 2
4.1.4 Top rollers ................................................................................................................................................................... 3
4.1.5 Throat plates ............................................................................................................................................................... 3
4.1.6 Throat plate inserts .................................................................................................................................................... 3
4.1.7 Connecting cables of the head to the drive ............................................................................................................. 3
4.2 Optional eqiupment ................................................................................................................................................ 3
5. Technical data ................................................................................................................................................................................... 4
6. Operation of the machine ................................................................................................................................................................. 5
6.1 Threading a thread ............................................................................................................................................... 5
6.2 Inserting the bobbin and threading the lower thread ............................................................................................ 5
6.3 Regulating the thread tension .............................................................................................................................. 6
6.4 Bobbin thread winding ........................................................................................................................................... 7
6.5 Needle replacement .............................................................................................................................................. 7
6.6 Regulation of pressing the top roller ..................................................................................................................... 7
6.7 Lifting the top roller up .......................................................................................................................................... 8
6.8 Reverse stitching .................................................................................................................................................. 8
6.9 Stitch length adjustment ....................................................................................................................................... 8
6.10 Safety clutch ........................................................................................................................................................... 8
7. Electronic control of the machine ................................................................................................................................... 9
7.1 Control of sewing by means of control elements .................................................................................................. 9
7.1.1 Via treadle ................................................................................................................................................... 9
7.1.2 Via control pushbutton panel ...................................................................................................................... 9
7.1.3 Via control panel V810/V 820 ...................................................................................................................... 9
7.2 Adjustment of automatic functions via control panel for stop motor ................................................................... 10
7.2.1 By using stop motor Efka with panel V 810 ............................................................................................... 10
7.2.1.1 Adjustment by means of buttons with fixed setting function ........................................................ 10
7.2.1.2 Setting by means of parameters ................................................................................................... 11
7.2.2 By using stop motor Efka with panel V 820 ............................................................................................... 12
7.2.2.1 Adjustment by means of buttons with fixed setting function ........................................................ 13
7.2.2.2 Setting by means of parameters ................................................................................................... 13
8. Maintenance ....................................................................................................................................................................................... 14
Operating instructions for eventual trouble shooting ................................................................................................................ 15

Foreword
This instruction manual is intended to help the user to become familiar with the machine and take advantage of its application
possibilities in accordance with the recommendations.
The instruction manual contains important information on how to operate the machine securely, properly and economically.
Observation of the instructions eliminates danger, reduces costs for repair and down-times, and increases the reliability and life
of the machine.
The instruction manual is intended to complement existing national accident prevention and environment protection regulations.
The instruction manual must always be available at the machine/sewing unit.
The instruction manual must be read and applied by any person that is authorized to work on the machine/sewing unit. This
means:
- Operation, including equipping, troubleshooting during the work cycle, removing of fabric waste
- Service (maintenance, inspection, repair and/or)
- Transport.
The user also has to assure that only authorized personnel work on the machine.
The user is obliged to check the machine at least once per shift for apparent damages and to immediatly report any changes
(including the performance in service), which impair the safety.
The user company must ensure that the machine is only operated in perfect working order.
Never remove or disable any safety devices.
If safety devices need to be removed for equipping, repairing or maintaining, the safety devices must be remounted directly after
completion of the maintenance and repair work.
Unauthorized modification of the machine rules out liability of the manufacturer for damage resulting from this.
Observe all safety and danger recommendations on the machine/unit! The yellow-and-black striped surfaces designate permanend
danger areas, eg danger of squashing, cutting, shearing or collision.
Besides the recommendations in this instruction manual also observe the general safety and accident prevention regulations!

General safety instructions
The non-observance of the following safety instructions can cause bodily injuries or damages to the machine.
1. The machine must only be commissioned of the instruction book and operated by persons with appropriate training.
2. Before putting into service also read the safety rules and instructions of the motor supplier.
3. The machine must be used only for the purpose intended. Use of the machine without the safety devices is not permitted. Observe
all the relevant safety regulations.
4. When gauge parts are exchanged (e.g. needle, top roller, needle plate, feed dog and bobbin) when tread-ing, when the workplace is
left, and during service work, the machine must be disconnected from the mains by switching off the master switch or disconnecting
the mains plug.
5. Daily servicing work must be carried out only by appropriately trained persons.
6. Repairs, conversion and special maintenance work must only be carried out by technicians or persons with appropriate training.
7. For service or repair work on pneumatic systems the machine must be disconnected from the compressed air supply system.
Exceptions to this are only adjustments and functions checks made by appropriately trained technicians.
8. Work on the electrical equipment must be carried out only by electricians or appropriately trained persons.
9. Work on parts and systems under electric current is not permitted, except as specified in regulations DIN VDE 0105.
10. Conversion or changes to the machine must be authorized by us and made only in adherence to all safety regulations.
11. For repairs, only replacement parts approved by us must be used.
12. Commissioning of the sewing head is prohibited until such time as the entire sewing unit is found to comply with EC directives.
It is absolutely necessary to respect the safety instructions marked by these signs.
Danger of bodily injuries !
Please note also the general safety instructions.
IMPORTANT WARNING!
To the feeding network cord, it is necessary to connect the respective network plug which has been approved in the country
of utilizing the machine. This operation should be performed by a worker acquainted with the electric safety rules being in
force in the given country. The supplier is not responsible for any damages caused by defective plug or owing to incorrect
assembly of the plug.
In spite of all safety measures made on the machines, inappropriate actions of the operator may lead to dangerous situations. In
industrial sewing machines, attention should be paid to the following still remaining possible sources of injury:
1. Moving sewing needle
- risk of injury when sewing with raised pressure foot or top roller, because the finger guard is then positioned too high.
2. Moving thread take-up lever
- risk of injury when inadvertently or intentionally inserting the finger(s) between the thread take-up lever and its guard.
3. Moving pressure member
- risk of injury when holding sewn work in immediate vicinity of the pressure member and beginning to insert under the pressure
member a considerably thicker sewn work portion,
- risk of injury when sinking the pressure member.
4. When switched off, the clutch motor slows down by inertia but would be reactivated by an accidental tread-ing down of the motor
treadle. To avoid such risk, it is advised to hold the handwheel by hand and slightly to depress the motor treadle.

1
Part A - Instruction manual
1. Proper use of the machine
The machine can be used in the shoemaking industry for sewing of light medium and heavy shoe uppers. It is suitable for sewing
natural and man made leathers, shoemaking textiles and even plastic parts of sports shoes.
The machine is also used in the fancy goods industry for sewing bags, handbags, rucksacks and cases from the usual fancy
goods materials.
The machine sews with a double needle stitch. It is standardly equipped with needles of the 134 KKLR system which are suitable
for sewing leather. When sewing textile materials it is necessary to install the needle of the 134 system. The machine enables the
sewing of both technical and decorative seams which have almost the constant length of the stitch at a different sewing speed.
Only a dry material, which cannot be thicker than 6 mm when depressed by top roller, can be sewn by these machines, generally.
The material cannot contain any hard subjects, to the contrary case it is possible to work only with applied eye-protective shield.
Such a shield is not available to delivery at this time. Generally threads up to size 1000 dtex x 1 x 3 (Labelled number 10) have been
used namely synthetic, cotton or core threads. Whoever should like to use other special threads, that one should consider the
resulting risks and make appropriate safety measures.
The total thickness is determined by sewing with a thicker needle of very strong material. In cases like this it is also necessary
substantially reduce the speed of sewing below the value shown in paragraph 5.
These special machines may be installed a operated only in dry and kept up expanses. We, as industrial sewing machines
manufacturers, agree with the fact that our products are operated, at the least, so far learned operators who can carry out all usual
operating functions and suppose their possible risks as perceptible.
Machine noisiness
Machine noisiness has been measured in accordance with the standards ISO 3746, ISO 11204 at maximum speed.
Laeq = equivalent machine noise of the self-standing machine on the working place, converted to % machine employment (dB)
- stated in the table
2. Description of the machine
It is double-needle machine. It sews with a double threaded lock-stitch. It has a lower circular feed, needle feed and a top roller
which is driven. There are two possibilities for feeding. At the first step it feeds a lower circular feed, needle and top roller.
Secondly it feeds only the circular feed and the top roller (the needle is above the throat plate). Feeding can be in both directions.
The stitch length can be adjusted with an adjusting dial. The feeding mechanism can be adjusted to two systems after removing
the rear cover:
1. Stitch length up to 4 mm at max. sewing speed up to 2500 rpm.
2. Stitch length up to 5 mm at max. sewing speed up to 1600 rpm.
Caution!
Maximum allowed speed must not be exceeded for the given system of sewing. Otherwise it can cause damage to the
feeding mechanism.
The machine is fitted with two large-size vertical hooks protected by an safety clutch.
The machine uses a wick lubrication system with central oil supply. The hooks are lubricated from an independent oil source.
The simplest sub-class is standardly equipped with a knee operated lever. Specially for the Czech republic and if required with
treadle. Reverse stitching is with a manually operated lever.
Higher sub-classes have always mechanical control like the simplest sub-class, and furthermore there is a possibility of levelling
the needle, thread trimmer, electromagnetic top roller lift and electromagnetic reverse stitching (according to your order).
Each sub-class can be delivered in four sewing categories. Sewing category is determined by the number of the thread label and
the corresponding number of the needle. Each sewing category is available with a range of needle distances. In the factory, the
machine has been adjusted to the ordered needle distance and sewing category. Readjustments to another needle distance or
sewing category should be carried out by an experienced mechanician. A stand is in the simplest sub-class equipped with a lever
clutch motor and if required with a stop motor which enables the levelling of the needle.
In higher sub-classes, the stop motor is either situated on the machine table top or as a minimotor integrated on the machine
head. The type of mechanical top roller lift depending on the stand has one or two treadles.
Type of the Noisiness % machine
machine dB employment
1280i-XXX-100 82 20
1280i-XXX-200 79 20
1280i-XXX-300 73 20
1280i-XXX-400 70 20

2
3. Machine sub-classes and sewing categories
3.1 Sub-class
Table 1
3.2 Sewing categories
This code indication includes the equipment assembled on the machine head, both necessary equipment and optional equip-
ment. The standard configuration of the equipment has been preset, according to the under mentioned table, in the factory which
includes only necessary equipment. If the buyer demands a different configuration then the factory allocates a new code
indication.
Table 2
Standard configuration - the numbers in brackets stand for ordering Nos. when ordering separately the Equipment in question
4. Survey of equipment
This survey does not include the equipment assembled on the stand.
4.1 Basic necessary equipment (at least one of each from the following group of equipment
is assembled)
4.1.1 Needles
M 132 - needle 134 LR size 80 Schmetz
M 133 - needle 134 LR size 90 Schmetz
M 134 - needle 134 KKLR size 130 Schmetz
M 135 - needle 134 KKLR size 160 Schmetz
4.1.2 Wheel feeders
M 083 - wheel feeder with pitch of teeth 0.6 mm
M 082 - wheel feeder with pitch of teeth 1.2 mm
4.1.3 Top roller holders
M 156 - holder for the top roller ø 25 mm
M 157 - holder for the top roller ø 35 mm
M 295 - holder for the top roller ø 45 mm
Type of Top roller lift Reverse stitching Thread
the machine trimmer
Class-subclass Via knee Treadle Via electro- Via electro- Via hand Via electro-
-sewing lever mag. + mag. + lever mag. +
category knee lever treadle hand lever
1280i-611-XXX
1280i-621-XXX
1280i-647-XXX
1280i-657-XXX
••••
•
••
••
•
1280i-6XX-100 1,2 80 35 0,6 1,2
(M 024) (S548 000255) (M 173) (M 083) (M 111)
1280i-6XX-200 1,6 90 35 0,6 1,5
(M 025) (S548 000260) (M 173) (M 083) (M 030)
1280i-6XX-300 2,0 130 35 0,6 2,0
(M 026) (S548 000312) (M 173) (M 083) (M 115)
1280i-6XX-400 2,4 160 35 1,2 2,4
(M 027) (S548 000325) (M 173) (M 082) (M 118)
Type Needle distance Needle size Top roller Wheel feeder Throat plate
insert
Class-sub-class Throat plate Diameter Pitch of teeth Width of hole
-sewing category mm 0.01mm mm mm mm
.

3
4.1.4 Top rollers
M 172 - top roller ø 25 mm
M 173 - top roller ø 35 mm
M 174 - rubberized top roller ø 25 mm
M 175 - rubberized top roller ø35 mm
M 310 - smooth top roller ø 25 mm
M 311 - smooth top roller ø 35 mm
M 296 - top roller ø 45 mm - width 2.0 mm
M 297 - top roller ø 45 mm - width 3.8 mm
4.1.5 Throat plates
M 024 - throat plate for needle distance of 1.2 mm
M 025 - throat plate for needle distance of 1.6 mm
M 026 - throat plate for needle distance of 2.0 mm
M 027 - throat plate for needle distance of 2.4 mm
M 028 - throat plate for needle distance of 3.2 mm
4.1.6 Throat plate inserts
M 111 - insert for throat plate for needle distance of 1.2 mm (for needle 60-80)
M 029 - insert for throat plate for needle distance of 1.6 mm (for needle 60-80)
M 030 - insert for throat plate for needle distance of 1.6 mm (for needle 80-110)
M 031 - insert for throat plate for needle distance of 1.6 mm (for needle 110-140)
M 114 - insert for throat plate for needle distance of 2.0 mm (for needle 80-110)
M 115 - insert for throat plate for needle distance of 2.0 mm (for needle 110-140)
M 032 - insert for throat plate for needle distance of 2.0 mm (for needle 140-160)
M 116 - insert for throat plate for needle distance of 2.4 mm (for needle 80-110)
M 117 - insert for throat plate for needle distance of 2.4 mm (for needle 110-140)
M 118 - insert for throat plate for needle distance of 2.4 mm (for needle 140-160)
M 119 - insert for throat plate for needle distance of 3.2 mm (for needle 140-160)
4.1.7 Connecting cables of the head to the drive
M 163 - connecting cable to the drive EFKA DC 1600/DA82GA; EFKA VD 552/6F82FA and EFKA VD 554/6F82FA
M 055 - connecting cable without any specified drive (with free cable end)
Note: For the machine provided with a minimotor, the cable is component part of the drive thereof.
4.2 Optional equipment
M 010 - built-in lighting (including transformer 230/12V)
M 018 - sewn work guide
M 149 - sewn work guide
M 198 - sewn work guide
M 194 - rear guide holder
M 242 - setting gauge
1280 611001V - high mortality spare parts kit in plastic box for sub-class without thread trimmer
1280 647001V - high mortality spare parts kit in plastic box for sub-class with thread trimmer
S794 222012 - halogen lighting (12 V, 20 W - contains transformer)

4
5. Technical data
Table 3
* The splice with the so-called spur is being mounted as a standard with the sewing categories 100 and 200 and is designed
for sewing thin materials. For sewing thicker materials with a maximum stitch length it is possible to use a splice without spur.
** Splice without spur is mounted as a standard with the sewing categories 300, 400.
Stitch type Double thread lock-stitch
Top roller stroke 5.5 ± 0.5 mm - via hand lever
12.5 mm via knee lever, treadle, electromagnet
Hook R 820 - vertical large
Needle System 134 KKLR
System 134 KK
Driving unit Lever clutch 4 poles change motor min. 0.4 kW,
lewer clutch 2 poles change motor min. 0.4 kW
Stopmotor min. 0.4 kW
Weight of the head max. 47 kg (53 kg head with minimotor)
Weitght of the stand max. 61 kg (38 kg for head with minimotor)
Opening space of machine head 267 x 125 mm
Dimension of bed plate 178 x 518 mm
Length of trimmed thread ends 8....11 mm
Input machine with clutch motor max. 700 W
Input machine with stop motor max. 800 W (600 W with minimotor)
Equivalent accoustic presser level of the sole machine
at work place by 20% use of the machine during
a shift under standard sewing conditions 82 dB/A
Layout dimensions of the machine (including the stand) 1060 x 550 mm
Height of the machine (including the stand and the thread stand) 1680 mm
Sewing Material Stitch Labelled Number Sewing Hook
category sewn length number of of needle speed
polyester thread
Standard
mm - mm mm - - 0,01mm 0,01mm SPM SPM
-100 0,8 2 2 3 70 80,70, 80 60-80 2500 2500 *
-light 60 R 820
-200 1 2 2,5 4 40 50,40, 90 80-110 2000 2000 *
-medium 30 R 820
-300 me- 1,5 1-2 3,5 5 20 25,20 130 110-140 1200 1600 **
dium-heavy R 820
-400
-heavy 2 1-2 4 5 10/20 20,10 160 140-160 800 1200 **
(decorative) R 820
Thickness of one
layer
Number of layers
Standard
Maximum
Standard
Range
Standard
Range
Standard
Maximum

5
6. Operation of the machine
6.1 Threading a thread
Caution! Risk of injury!
Before threading a thread, turn the main switch
off and wait until the machine stops!
Thread the threads as it is shown in picture.
Caution!
Not following the correct method of threading a
thread may cause serious damage to the function
of the machine.
6.2 Inserting the bobbin and threading the lower
thread
Caution! Risk of injury!
Turn the main switch off and wait until the motor
stops!
- Tilt the shutter (1) up.
- Insert the bobbin (2) with thread end (3) in the direction as
shown in the picture.
- Thread the thread through the notch (4) and the space (5)
and place under the spring (6).
- Cut off the thread end as shown.
2
2
3
3
6
41
6
1
~10
~10

6
6.3 Regulating the thread tension
The thread tension must conform to the thickness of the sewn
threads, thickness and hardness of sewn material (thin and
soft material will fold with high tension) and the kind of seam.
An ordinary fitting seam should be formed with stitches knit-
ted in the middle of the sewn material.
A decorative seam is mostly used with rough threads (10, 20)
on thin material and it has tied up threads on the reverse side
of the material for achieving a decorative appearance.
Thread tension adjustment is by standard sewing (table 3)
conditions in accordance with table No. 4.
If achieving of a decorative seam with stitch knitting on the
underside is wished, it is necessary to decrease the upper
thread tension, it is carried out by turning of nuts (1), in the
counter-clockwise sense.
Thread tension
Table 4
Sewing Kind of seam Identified Maximum
category value upper tension of
thread tension lower thread
NN
1- 31
2 - 4.5 1.5
3Fitting 8 2
Decorative 5
4Fitting 12 2
Decorative 10 2.5
If the maximum lower thread tension exceeds the
values given in table No. 4, it may cause problems
in the beginning of sewing after the previous
thread trim.
Measurement of tension is done by dynamometer.
Warning:
The upper thread tensioner has been loosened automatically
after every trimming and top roller lifting. In these cases the
thread tension cannot be measured.
Regulating the thread tension
Caution! Risk of injury!
Before regulating the lower thread tension, turn
the main switch off and wait until the motor stops.
The upper thread tension is adjusted with nuts (1). Its clock-
wise turning increases the tension.
The tension of the auxiliary tensioner (3) should beas low as
possible but it should be on a level so that the upper thread
would not pull out of the tensioner when the work is being
removed.
The lower thread tension is adjusted with a screw (2). Its clock-
wise turning increases the tension.
Tension correlation rate defines the depth of the seam tied
through. The result of raising the upper tension will be the
decreasing depth of tie through. The opposite will apply with
the lower thread.
2
3 3
1
Fitting seam
Decorative seam
Stitch knitting
Stitch knitting