Lab Report 2: Single Needle Lockstitch Machine – Comprehensive Analysis
1. Introduction
The Single Needle Lockstitch Machine is a fundamental sewing machine widely used in the
garment manufacturing industry. It creates a lockstitch using a single needle and a bobbin
thread, producing strong and precise seams. This machine is essential for various sewing
applications, including assembling garments, topstitching, and hemming.
2. Objectives
1.To understand the functionality and working mechanism of the Single Needle Lockstitch
Machine.
2.To analyze its significance in the garment industry.
3.To explore recent advancements and technical specifications of this machine.
4. To study its maintenance requirements and operational efficiency.
3. Function and Purpose
- Seam Construction: Joins fabric layers using a strong and durable lockstitch.
- Versatile Use: Suitable for sewing woven and knit fabrics, making it ideal for various
garment types.
- Precision Stitching: Ensures uniform stitch length and tension, contributing to high-quality
garments.
- Mass Production: Supports high-speed sewing, making it an essential machine for industrial
applications.
4. Technical Specifications
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Stitch Type: Lockstitch (Class 301)
Maximum Sewing Speed: Up to 5,500 stitches per minute (SPM)
Stitch Length: Adjustable up to 5 mm
Needle Bar Stroke: 35 mm
Presser Foot Lift:
o By Hand: 5.5 mm
o By Knee: 13 mm
Needle Type: DB×1 (#14) #9–#18 / 134 (Nm90)
Feed Dog: 3-row or 4-row
Hook Type: Automatic-lubricating full-rotary hook
Lubrication System: Automatic
Motor Type: Options include clutch motor or energy-efficient servo motor
Presser Foot Lift: Manual or automatic
 Fabric Feed Mechanism; Feed dog system
5. Maintenance
5.1. Regular Cleaning
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Dust and Lint Removal: After each use, remove lint and dust from the bobbin case,
under the needle plate, and around the feed dog using a soft brush or compressed air.
Deep Cleaning: Periodically, remove the needle, presser foot, slide plate, throat plate,
and bobbin case. Soak these parts in a cleaning solution to remove accumulated
grime.
5.2. Proper Oiling
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Lubrication Points: Refer to your machine's manual to identify oiling points. Apply
a drop of high-quality sewing machine oil to each designated spot to ensure smooth
operation.
Frequency: For machines in regular use, oiling once a week is recommended. In less
frequent use, oil monthly. Always clean the machine before oiling.
5.3. Routine Maintenance Checks
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Needle Inspection: Regularly inspect the needle for signs of wear or damage.
Replace if necessary to prevent issues like skipped stitches or fabric damage.
Thread Tension: Ensure that both upper and lower thread tensions are balanced to
produce even stitches. Adjust as needed based on fabric and thread type.
Bobbin Care: Clean the bobbin case to remove lint and check for any damage.
Proper bobbin maintenance ensures smooth thread delivery.
5.4. Professional Servicing
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Annual Check-Up: Even with regular maintenance, it's advisable to have your
machine professionally serviced annually. Technicians can adjust internal components
and address issues not apparent during routine checks.
6. Conclusion
The Single Needle Lockstitch Machine is a cornerstone of garment manufacturing, offering
high precision, durability, and efficiency. Regular maintenance and advancements in
technology further enhance its performance, making it an indispensable tool for the apparel
industry.
7. References
1.Technical Specifications: JUKI DDL-8700 Specifications
https://www.juki.co.jp/industrial_e/products_e/apparel_e/1needle_lock_e/
2.Working Mechanism: How a Sewing Machine Works :
https://www.youtube.com/watch?v=rUSecXVt-jU
3.Maintenance Guide: Lockstitch Machine Servicing
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https://pubs.nmsu.edu/_c/C102/index.html?utm_source=chatgpt.com
https://ncert.nic.in/vocational/pdf/ivsm104.pdf
https://ncert.nic.in/vocational/pdf/ivsm104.pdf