Computer-controlled, High-speed, Lockstitch, Button Sewing System

The machine achieves sewing speed of 2,700sti/min The machine’s thread-trimming etc. have been increased to significantly shorten total cycle time.  The LK-1903C is a lockstitch button sewing machine which is not only applicable to many different sewing specifications but also able to carry out cycle sewing and produces high-quality seams.

Product features

  • Higher productivity

    The LK-1903C achieves sewing speed of 2,700sti/min. The machine's starting, stopping, thread-trimming and automatic presser lifting speeds have been increased to significantly shorten total cycle time. This is a lockstitch button sewing machine that supports a variety of sewing patterns and cycle sewing.

  • Standard LCD panel / Control box integrated with the machine head

    The control box integrated with the machine head, originally designed by JUKI, is adopted. The number of standard patterns is 50. As many as 999 patterns (500,000 stitches) can be stored in memory. The new upright type operation panel is installed on the side face of the machine head to allow the operator to operate the machine without averting his/her eyes, during sewing, from the bartack being sewn. In addition, the table surface can be used widely. The operation panel can also be installed on the table as before.
    ●If you want to install the operation panel on the table, an optional connecting cable (1.2 m) will be necessary. Part number: 40297363

    Two-way data communication function for sewing machine data using an NFC terminal (optional)

    The standard LCD panel is provided as standard with a USB port to facilitate data management between sewing machines and update of software. If you additionally use the optional NFC terminal, bidirectional data communication is enabled with a commercially-available Android terminal in a non-contact manner. This enables quick sharing of pre-set sewing data with other sewing machines to reduce the time required for set-up changing.
    ●Optional NFC terminal: Part number 40289481

  • Bird’s nest preventing / Shorter-thread remaining specification (LK-1903CB)

    Users who are conscious about the finished quality of products manually nip, with scissors, the thread remaining on the material after thread trimming at the end of sewing. Now, the button sewing machine with the bird's nest preventing/shorter thread remaining functions saves such users the trouble of nipping the thread, thereby preventing the sewing product from being damaged by manual thread-nipping with scissors.

    The sewing machine eliminates so-called “bird’s nests” (thread tangling in on the wrong side of the material at the beginning of sewing).

    The thread is retained at the beginning of sewing and any excess thread is trimmed during sewing. As a result, the length of thread sewn in the seam is shortened, thereby achieving high-quality sewing
    performance while preventing thread from tangling in on the wrong side “of the material.”
    ●Use #60-80 (TEX22-30) polyester spun thread

    Length of thread remaining on the material at the end of sewing has been reduced to 2 mm or less*.

    The newly-developed shorter-thread remaining mechanism trims the thread shorter after the regular thread trimming operation. Additionally, thread waste produced by thread trimming is withdrawn by suction. Thanks to this mechanism, the trouble of manual thread nipping is avoided.
    * Remaining length of thread varies with sewing conditions

  • with button feeder (LK-1903C/BR35)

    ●The machine achieves sewing speed of 2,700sti/min.The machine’s starting, stopping, thread-trimming and automatic presser lifting speeds have been increased to significantly shorten total cycle time.
    ●With our original horizontal forced feed mechanism, the button carrier sets a button in position so that the operation is simplified. Even first-time operators can achieve stable sewing quality by simply setting the fabric and pressing the pedal.

    OPERATION PANEL (Button feeder)

    The variety of functions can be easily adjusted by the simplified operation panel. Alarm lamp will be activated when problem is detected so that proper measures can be taken quickly.

    Automatic supply mode
    The machine and button feeder are connected and run together. It starts sewing a button by pressing a pedal, thread trimmer is activated after sewing a button, and button feeder sets the next button in position automatically. The machine repeats these operations with this mode.
    Mode for individual
    This mode is for the machine only. As button feeder will not be activated, this can be used as a standard button sewing machine.
    Mode for small lots
    Same as the automatic mode, but parts feeder will not be activated. It discharges the required amount of buttons in the index and sews buttons automatically. This is suitable for smaller lots.

Basic performance

  • LK-1903C TABLE OF THE SEWING PATTERNS (No.1~50)
    LK-1903CB TABLE OF THE SEWING PATTERNS(No.1~No.22、No.34~No.45)

    Click here for the LK-1903C standard pattern list

  • The machine is provided as standard with the active tension (electronic thread tension control mechanism)

    ●Since the machine is provided with an active tension mechanism, it is able to set a needle thread tension that matches various sewing conditions (such as thread, material and sewing speed) on the operation panel, store the data in memory and reproduce it.
    ●The needle thread tension can be separated according to stitching type or portion of a seam, such as the beginning part of the seam, in the middle of sewing and end ofthe seam (fastening stitch).

  • Excellent seam quality

    Needle thread grasping mechanism helps produce consistent knot tying at the beginning of sewing. (This device has been factory-set to “invoking prohibited” status at the time of delivery.)
    ●In the case “T” is selected for the work clamp foot/thread clamp

  • Auto-lifter mechanism utilizing a system

    ●The machine is provided as standard with auto-lifter that uses a stepping-motor system. This helps reduce operator fatigue.
    ●It is also possible to change over the stroke of the auto-lifter from a onestep stroke to a double-step stroke, which offers easier positioning of a material on the machine. For the double-step stroke, an intermediate stopping height can be established on the operation panel.
    ●The work clamp foot lift can be set to a maximum of 13mm.

  • The sewing starting point can be corrected

    The sewing starting point can be moved in the X and/or Y directions. The position of the sewing pattern can be corrected in accordance with the shape of the work clamp foot.

  • Oil stains are eliminated

    ●Thanks to our advanced dry-head technology, the frame (needle bar and thread take-up) no longer requires lubrication. This prevents the material from being stained with lubricating oil.
    ●Just a small quantity of clean oil is supplied from the oil tank to the hook.

  • Excellent workability and operability (Low-noise and low-vibration)

    ●The direct-drive head (with no belt), which is directly connected to a compact AC servomotor, achieves outstanding. This head helps create a comfortable working environment with reduced vibration and noise.
    ●The arm section of the machine head is fitted with a hand pulley. This allows the operator to visually check the needle entry points.

  • Many different sewing patterns

    The machine is provided as standard with 100 different sewing patterns. The machine permits easy changeover of sewing patterns for effortless execution of an inexhaustible range of sewing specifications.

  • Operator’s fatigue is reduced

    The LED hand light is now provided with color matching function using two colors (white/light bulb color) in addition to the conventional dimming function. Illumination is adjustable in five levels and dimming is in 10 levels to help reduce the eye fatigue of the operator who is engaged in sewing operation for extended hours.

  • Noise are reduced

    This machine substantially reduces noise in comparison with the predecessor models to provide the wok environment that takes reduction of the operator's fatigue into consideration.
    ●Reduction of noise of the sewing machine by approximately 40%...... Stress on the ears is relieved

  • Environmental-friendly power saving

    Aiming at the creation of environment-conscious products, an encoder is mounted on the stepping motor. Thanks to the JUKI’s unique control technology, power consumption of this machine is reduced by approximately 26% in comparison with the predecessor model.

Specification

Model name LK-1903C LK-1903C/BR35 LK-1903CB
Max. sewing speed 2,700sti/min*
Button size Type : Round-shaped, flat button
Size : φ8~φ32mm
301 : φ8~φ20
302 : φ10~φ20
OPTION : φ15~φ32
Type: Round-shaped, flat button (2-holed, 4-holed)
Size: φ9~20mm
For small button: φ10~φ15mm
For medium-sized button: φ12~φ18mm
(Those that are smaller than φ10mm or
larger than φ18mm must be specially ordered.)
Thickness: 1.8~3.5mm
Type: Round-shaped, flat button
Size: φ8~φ20mm
301: φ8~φ20
Stitch length 0.1~10mm (0.1mm step)
Needle bar stroke 45.7mm
Lift of the work clamp foot Max. 13mm Max. 11mm Max. 10mm
Auto-lifter Provided as standard (stepping motor type)
Needle thread tension Active tension (electronic thread tension control system)
Needle (at the time of delivery) DP×17 (#14) DP×17 (#11, #14)
Hook Standard  hook
Number of stitches that
can be stored in memory
Max. 500,000 stitches
Number of standard patterns 50 patterns
Number of data that can be input 200 patterns 34 patterns
Number of data that can be input 999 patterns
Enlarging/Reducing facility 20~200%(1% step), Pattern enlargement /reduction can be done by increasing /decreasing the stitch length
Memory medium Internal-organs memory
Bobbin thread counter Provided as standard (up/down method)
Bird's nest preventing /
Shorter-thread remaining functions
- Provided
Supplying and sorting of button Vibration system
Button feed Horizontal forced button-feed mechanism
Button feed mode Horizontal forced button-feed mechanism
Automatic feed mode, non-feed mode,
and small-lot sewing mode
Lubrication Hook: minute-quantity lubrication
Lubricating oil JUKI New Defrix Oil No.2 (equivalent to ISO VG32)
Sewing machine motor Compact AC servomotor (direct-drive system)
Power consumption 3-phase 200-240V / 230VA 3-phase 200V / 320VA 3-phase 200-240V / 230VA
Weight Machine head (Control box, motor, panel) 56.9kg Machine head (Control box, motor, panel) and BR35 146kg Machine head (Control box, motor, panel) 56.9kg
Air consumption - 6 L/cycle

*“sti/min” stands for “Stiches per Minute”
*Other company names and product names/brand names are trademarks or registered trademarks of the respective companies.

When you place orders