4 Thread Computerized Full Auto Overlock Sewing Machine
Model: OL-747D / OL-757D
Specification OL-747D OL-757D Max Sewing Speed 5500 stitches/min 5000 stitches/min Stitch Length Range 1.0–4.0 mm adjustable 1.0–5.0 mm adjustable Max Sewing Thickness 6 mm (light & medium shoe lining) 8 mm (thick reinforcement & multi-layer fabric) Needle Specification DC×1, No.9–No.16 DC×1, No.11–No.18 Thread Configuration 4-thread overlock, firm edge sealing 4-thread overlock, firm edge sealing Core Functions Auto thread trimmer, auto presser foot lift, differential feed Auto thread trimmer, auto presser foot lift, differential feed Drive System Direct drive servo motor, silent energy-saving Direct drive servo motor, silent energy-saving Control Panel Digital operation panel Digital operation panel Applicable Materials Shoe upper lining, reinforcement fabric, synthetic leather, mesh, interlining Thick lining, multi-layer reinforcement, leather edge, webbing trim Presser Foot Lift 5 mm manual / 10 mm pneumatic 6 mm manual / 12 mm pneumatic Working Power 0.55 KW 0.75 KW Working Voltage AC220V 50Hz AC220V 50Hz Machine Size (L×W×H) 1200×600×1150mm (with stand & table) 1200×600×1180mm (with stand & table) Wooden Box Size (L×W×H) 1280×680×1250mm 1280×680×1280mm Net Weight 70 KG 80 KG Gross Weight 90 KG 105 KG
Key Machine Features
· Direct drive servo motor, low noise, stable high-speed operation and long service life
· 4-thread overlock stitching, tight and firm edge sealing, prevent lining fraying
· Automatic thread trimming & presser foot lift, reduce manual operation and improve efficiency
· Differential feed adjustment, avoid fabric stretching or shrinking during edge locking
· Adjustable stitch length, fit thin mesh lining and thick reinforcement material
· Digital panel, intuitive parameter setting, easy for workers to master
· Wear-resistant rotary hook, adapts to long-time continuous batch production
· Detachable needle plate & feed dog, easy to clean thread scraps and daily maintenance
· Thread break detection function, stop timely to reduce defective shoe lining parts
· Energy-saving servo system, lower power consumption than traditional clutch motor
· Overload and overheat protection, extend motor service life
Application Fields
This 4 Thread Computerized Overlock Sewing Machine serves footwear production workshops, shoe lining processing plants, leather goods factories and apparel accessory lines. It performs edge locking and overlocking on shoe upper linings, reinforcement interlinings, mesh fabrics, synthetic leather cut pieces and webbing trims, preventing fabric fraying and improving shoe part durability.
Ideal for edge processing of sports shoe linings, casual shoe uppers, children shoe reinforcement pieces and bag lining fabrics. Adjustable stitch and differential parameters adapt to materials of different thicknesses, delivering neat and firm locked edges to meet mass shoemaking quality and efficiency requirements.
Operation Guidance
- Check power supply, needle condition and thread threading before startup
- Adjust stitch length, differential feed ratio and thread tension according to material
- Test sew on small material sample to confirm edge effect before formal production
- Place lining cut piece flat under presser foot, control pedal to complete automatic overlocking
- Clean thread scraps and dust on machine surface, cut off power after daily work
Installation Guidance
- Place the machine stand on flat solid ground, fix table board stably
- Connect AC220V power supply with reliable grounding wire
- Install needle, thread stand and auxiliary accessories following operation manual
- Run 3–5 minutes no-load test, finish stitch tension debugging with sample shoe materials
Maintenance & Repair Instructions
Daily Maintenance
Clean surface thread scraps and dust; lubricate needle bar and rotary hook, check thread passing path
Weekly Maintenance
Inspect feed dog and needle plate wear, tighten loose screws and test thread break detection function
Monthly Maintenance
Deep clean internal thread accumulation, check motor belt tension and replace severely worn parts timely
Repair Rules
Solve faults according to touch screen error prompts; cut off power before disassembly; replace worn rotary hook and needle regularly to guarantee stitching quality

4 Thread Computerized Full Auto Overlock Sewing Machine
Model: OL-747D / OL-757D
Specification OL-747D OL-757D Max Sewing Speed 5500 stitches/min 5000 stitches/min Stitch Length Range 1.0–4.0 mm adjustable 1.0–5.0 mm adjustable Max Sewing Thickness 6 mm (light & medium shoe lining) 8 mm (thick reinforcement & multi-layer fabric) Needle Specification DC×1, No.9–No.16 DC×1, No.11–No.18 Thread Configuration 4-thread overlock, firm edge sealing 4-thread overlock, firm edge sealing Core Functions Auto thread trimmer, auto presser foot lift, differential feed Auto thread trimmer, auto presser foot lift, differential feed Drive System Direct drive servo motor, silent energy-saving Direct drive servo motor, silent energy-saving Control Panel Digital operation panel Digital operation panel Applicable Materials Shoe upper lining, reinforcement fabric, synthetic leather, mesh, interlining Thick lining, multi-layer reinforcement, leather edge, webbing trim Presser Foot Lift 5 mm manual / 10 mm pneumatic 6 mm manual / 12 mm pneumatic Working Power 0.55 KW 0.75 KW Working Voltage AC220V 50Hz AC220V 50Hz Machine Size (L×W×H) 1200×600×1150mm (with stand & table) 1200×600×1180mm (with stand & table) Wooden Box Size (L×W×H) 1280×680×1250mm 1280×680×1280mm Net Weight 70 KG 80 KG Gross Weight 90 KG 105 KG
Key Machine Features
· Direct drive servo motor, low noise, stable high-speed operation and long service life
· 4-thread overlock stitching, tight and firm edge sealing, prevent lining fraying
· Automatic thread trimming & presser foot lift, reduce manual operation and improve efficiency
· Differential feed adjustment, avoid fabric stretching or shrinking during edge locking
· Adjustable stitch length, fit thin mesh lining and thick reinforcement material
· Digital panel, intuitive parameter setting, easy for workers to master
· Wear-resistant rotary hook, adapts to long-time continuous batch production
· Detachable needle plate & feed dog, easy to clean thread scraps and daily maintenance
· Thread break detection function, stop timely to reduce defective shoe lining parts
· Energy-saving servo system, lower power consumption than traditional clutch motor
· Overload and overheat protection, extend motor service life
Application Fields
This 4 Thread Computerized Overlock Sewing Machine serves footwear production workshops, shoe lining processing plants, leather goods factories and apparel accessory lines. It performs edge locking and overlocking on shoe upper linings, reinforcement interlinings, mesh fabrics, synthetic leather cut pieces and webbing trims, preventing fabric fraying and improving shoe part durability.
Ideal for edge processing of sports shoe linings, casual shoe uppers, children shoe reinforcement pieces and bag lining fabrics. Adjustable stitch and differential parameters adapt to materials of different thicknesses, delivering neat and firm locked edges to meet mass shoemaking quality and efficiency requirements.
Operation Guidance
- Check power supply, needle condition and thread threading before startup
- Adjust stitch length, differential feed ratio and thread tension according to material
- Test sew on small material sample to confirm edge effect before formal production
- Place lining cut piece flat under presser foot, control pedal to complete automatic overlocking
- Clean thread scraps and dust on machine surface, cut off power after daily work
Installation Guidance
- Place the machine stand on flat solid ground, fix table board stably
- Connect AC220V power supply with reliable grounding wire
- Install needle, thread stand and auxiliary accessories following operation manual
- Run 3–5 minutes no-load test, finish stitch tension debugging with sample shoe materials
Maintenance & Repair Instructions
Daily Maintenance
Clean surface thread scraps and dust; lubricate needle bar and rotary hook, check thread passing path
Weekly Maintenance
Inspect feed dog and needle plate wear, tighten loose screws and test thread break detection function
Monthly Maintenance
Deep clean internal thread accumulation, check motor belt tension and replace severely worn parts timely
Repair Rules
Solve faults according to touch screen error prompts; cut off power before disassembly; replace worn rotary hook and needle regularly to guarantee stitching quality

4 Thread Computerized Full Auto Overlock Sewing Machine
Model: OL-747D / OL-757D
Specification OL-747D OL-757D Max Sewing Speed 5500 stitches/min 5000 stitches/min Stitch Length Range 1.0–4.0 mm adjustable 1.0–5.0 mm adjustable Max Sewing Thickness 6 mm (light & medium shoe lining) 8 mm (thick reinforcement & multi-layer fabric) Needle Specification DC×1, No.9–No.16 DC×1, No.11–No.18 Thread Configuration 4-thread overlock, firm edge sealing 4-thread overlock, firm edge sealing Core Functions Auto thread trimmer, auto presser foot lift, differential feed Auto thread trimmer, auto presser foot lift, differential feed Drive System Direct drive servo motor, silent energy-saving Direct drive servo motor, silent energy-saving Control Panel Digital operation panel Digital operation panel Applicable Materials Shoe upper lining, reinforcement fabric, synthetic leather, mesh, interlining Thick lining, multi-layer reinforcement, leather edge, webbing trim Presser Foot Lift 5 mm manual / 10 mm pneumatic 6 mm manual / 12 mm pneumatic Working Power 0.55 KW 0.75 KW Working Voltage AC220V 50Hz AC220V 50Hz Machine Size (L×W×H) 1200×600×1150mm (with stand & table) 1200×600×1180mm (with stand & table) Wooden Box Size (L×W×H) 1280×680×1250mm 1280×680×1280mm Net Weight 70 KG 80 KG Gross Weight 90 KG 105 KG
Key Machine Features
· Direct drive servo motor, low noise, stable high-speed operation and long service life
· 4-thread overlock stitching, tight and firm edge sealing, prevent lining fraying
· Automatic thread trimming & presser foot lift, reduce manual operation and improve efficiency
· Differential feed adjustment, avoid fabric stretching or shrinking during edge locking
· Adjustable stitch length, fit thin mesh lining and thick reinforcement material
· Digital panel, intuitive parameter setting, easy for workers to master
· Wear-resistant rotary hook, adapts to long-time continuous batch production
· Detachable needle plate & feed dog, easy to clean thread scraps and daily maintenance
· Thread break detection function, stop timely to reduce defective shoe lining parts
· Energy-saving servo system, lower power consumption than traditional clutch motor
· Overload and overheat protection, extend motor service life
Application Fields
This 4 Thread Computerized Overlock Sewing Machine serves footwear production workshops, shoe lining processing plants, leather goods factories and apparel accessory lines. It performs edge locking and overlocking on shoe upper linings, reinforcement interlinings, mesh fabrics, synthetic leather cut pieces and webbing trims, preventing fabric fraying and improving shoe part durability.
Ideal for edge processing of sports shoe linings, casual shoe uppers, children shoe reinforcement pieces and bag lining fabrics. Adjustable stitch and differential parameters adapt to materials of different thicknesses, delivering neat and firm locked edges to meet mass shoemaking quality and efficiency requirements.
Operation Guidance
- Check power supply, needle condition and thread threading before startup
- Adjust stitch length, differential feed ratio and thread tension according to material
- Test sew on small material sample to confirm edge effect before formal production
- Place lining cut piece flat under presser foot, control pedal to complete automatic overlocking
- Clean thread scraps and dust on machine surface, cut off power after daily work
Installation Guidance
- Place the machine stand on flat solid ground, fix table board stably
- Connect AC220V power supply with reliable grounding wire
- Install needle, thread stand and auxiliary accessories following operation manual
- Run 3–5 minutes no-load test, finish stitch tension debugging with sample shoe materials
Maintenance & Repair Instructions
Daily Maintenance
Clean surface thread scraps and dust; lubricate needle bar and rotary hook, check thread passing path
Weekly Maintenance
Inspect feed dog and needle plate wear, tighten loose screws and test thread break detection function
Monthly Maintenance
Deep clean internal thread accumulation, check motor belt tension and replace severely worn parts timely
Repair Rules
Solve faults according to touch screen error prompts; cut off power before disassembly; replace worn rotary hook and needle regularly to guarantee stitching quality

4 Thread Computerized Full Auto Overlock Sewing Machine
Model: OL-747D / OL-757D
Specification OL-747D OL-757D Max Sewing Speed 5500 stitches/min 5000 stitches/min Stitch Length Range 1.0–4.0 mm adjustable 1.0–5.0 mm adjustable Max Sewing Thickness 6 mm (light & medium shoe lining) 8 mm (thick reinforcement & multi-layer fabric) Needle Specification DC×1, No.9–No.16 DC×1, No.11–No.18 Thread Configuration 4-thread overlock, firm edge sealing 4-thread overlock, firm edge sealing Core Functions Auto thread trimmer, auto presser foot lift, differential feed Auto thread trimmer, auto presser foot lift, differential feed Drive System Direct drive servo motor, silent energy-saving Direct drive servo motor, silent energy-saving Control Panel Digital operation panel Digital operation panel Applicable Materials Shoe upper lining, reinforcement fabric, synthetic leather, mesh, interlining Thick lining, multi-layer reinforcement, leather edge, webbing trim Presser Foot Lift 5 mm manual / 10 mm pneumatic 6 mm manual / 12 mm pneumatic Working Power 0.55 KW 0.75 KW Working Voltage AC220V 50Hz AC220V 50Hz Machine Size (L×W×H) 1200×600×1150mm (with stand & table) 1200×600×1180mm (with stand & table) Wooden Box Size (L×W×H) 1280×680×1250mm 1280×680×1280mm Net Weight 70 KG 80 KG Gross Weight 90 KG 105 KG
Key Machine Features
· Direct drive servo motor, low noise, stable high-speed operation and long service life
· 4-thread overlock stitching, tight and firm edge sealing, prevent lining fraying
· Automatic thread trimming & presser foot lift, reduce manual operation and improve efficiency
· Differential feed adjustment, avoid fabric stretching or shrinking during edge locking
· Adjustable stitch length, fit thin mesh lining and thick reinforcement material
· Digital panel, intuitive parameter setting, easy for workers to master
· Wear-resistant rotary hook, adapts to long-time continuous batch production
· Detachable needle plate & feed dog, easy to clean thread scraps and daily maintenance
· Thread break detection function, stop timely to reduce defective shoe lining parts
· Energy-saving servo system, lower power consumption than traditional clutch motor
· Overload and overheat protection, extend motor service life
Application Fields
This 4 Thread Computerized Overlock Sewing Machine serves footwear production workshops, shoe lining processing plants, leather goods factories and apparel accessory lines. It performs edge locking and overlocking on shoe upper linings, reinforcement interlinings, mesh fabrics, synthetic leather cut pieces and webbing trims, preventing fabric fraying and improving shoe part durability.
Ideal for edge processing of sports shoe linings, casual shoe uppers, children shoe reinforcement pieces and bag lining fabrics. Adjustable stitch and differential parameters adapt to materials of different thicknesses, delivering neat and firm locked edges to meet mass shoemaking quality and efficiency requirements.
Operation Guidance
- Check power supply, needle condition and thread threading before startup
- Adjust stitch length, differential feed ratio and thread tension according to material
- Test sew on small material sample to confirm edge effect before formal production
- Place lining cut piece flat under presser foot, control pedal to complete automatic overlocking
- Clean thread scraps and dust on machine surface, cut off power after daily work
Installation Guidance
- Place the machine stand on flat solid ground, fix table board stably
- Connect AC220V power supply with reliable grounding wire
- Install needle, thread stand and auxiliary accessories following operation manual
- Run 3–5 minutes no-load test, finish stitch tension debugging with sample shoe materials
Maintenance & Repair Instructions
Daily Maintenance
Clean surface thread scraps and dust; lubricate needle bar and rotary hook, check thread passing path
Weekly Maintenance
Inspect feed dog and needle plate wear, tighten loose screws and test thread break detection function
Monthly Maintenance
Deep clean internal thread accumulation, check motor belt tension and replace severely worn parts timely
Repair Rules
Solve faults according to touch screen error prompts; cut off power before disassembly; replace worn rotary hook and needle regularly to guarantee stitching quality

4 Thread Computerized Full Auto Overlock Sewing Machine
Model: OL-747D / OL-757D
Specification OL-747D OL-757D Max Sewing Speed 5500 stitches/min 5000 stitches/min Stitch Length Range 1.0–4.0 mm adjustable 1.0–5.0 mm adjustable Max Sewing Thickness 6 mm (light & medium shoe lining) 8 mm (thick reinforcement & multi-layer fabric) Needle Specification DC×1, No.9–No.16 DC×1, No.11–No.18 Thread Configuration 4-thread overlock, firm edge sealing 4-thread overlock, firm edge sealing Core Functions Auto thread trimmer, auto presser foot lift, differential feed Auto thread trimmer, auto presser foot lift, differential feed Drive System Direct drive servo motor, silent energy-saving Direct drive servo motor, silent energy-saving Control Panel Digital operation panel Digital operation panel Applicable Materials Shoe upper lining, reinforcement fabric, synthetic leather, mesh, interlining Thick lining, multi-layer reinforcement, leather edge, webbing trim Presser Foot Lift 5 mm manual / 10 mm pneumatic 6 mm manual / 12 mm pneumatic Working Power 0.55 KW 0.75 KW Working Voltage AC220V 50Hz AC220V 50Hz Machine Size (L×W×H) 1200×600×1150mm (with stand & table) 1200×600×1180mm (with stand & table) Wooden Box Size (L×W×H) 1280×680×1250mm 1280×680×1280mm Net Weight 70 KG 80 KG Gross Weight 90 KG 105 KG
Key Machine Features
· Direct drive servo motor, low noise, stable high-speed operation and long service life
· 4-thread overlock stitching, tight and firm edge sealing, prevent lining fraying
· Automatic thread trimming & presser foot lift, reduce manual operation and improve efficiency
· Differential feed adjustment, avoid fabric stretching or shrinking during edge locking
· Adjustable stitch length, fit thin mesh lining and thick reinforcement material
· Digital panel, intuitive parameter setting, easy for workers to master
· Wear-resistant rotary hook, adapts to long-time continuous batch production
· Detachable needle plate & feed dog, easy to clean thread scraps and daily maintenance
· Thread break detection function, stop timely to reduce defective shoe lining parts
· Energy-saving servo system, lower power consumption than traditional clutch motor
· Overload and overheat protection, extend motor service life
Application Fields
This 4 Thread Computerized Overlock Sewing Machine serves footwear production workshops, shoe lining processing plants, leather goods factories and apparel accessory lines. It performs edge locking and overlocking on shoe upper linings, reinforcement interlinings, mesh fabrics, synthetic leather cut pieces and webbing trims, preventing fabric fraying and improving shoe part durability.
Ideal for edge processing of sports shoe linings, casual shoe uppers, children shoe reinforcement pieces and bag lining fabrics. Adjustable stitch and differential parameters adapt to materials of different thicknesses, delivering neat and firm locked edges to meet mass shoemaking quality and efficiency requirements.
Operation Guidance
- Check power supply, needle condition and thread threading before startup
- Adjust stitch length, differential feed ratio and thread tension according to material
- Test sew on small material sample to confirm edge effect before formal production
- Place lining cut piece flat under presser foot, control pedal to complete automatic overlocking
- Clean thread scraps and dust on machine surface, cut off power after daily work
Installation Guidance
- Place the machine stand on flat solid ground, fix table board stably
- Connect AC220V power supply with reliable grounding wire
- Install needle, thread stand and auxiliary accessories following operation manual
- Run 3–5 minutes no-load test, finish stitch tension debugging with sample shoe materials
Maintenance & Repair Instructions
4 Thread Computerized Full Auto Overlock Sewing Machine
Model: OL-747D / OL-757D
| Specification | OL-747D | OL-757D |
|---|---|---|
| Max Sewing Speed | 5500 stitches/min | 5000 stitches/min |
| Stitch Length Range | 1.0–4.0 mm adjustable | 1.0–5.0 mm adjustable |
| Max Sewing Thickness | 6 mm (light & medium shoe lining) | 8 mm (thick reinforcement & multi-layer fabric) |
| Needle Specification | DC×1, No.9–No.16 | DC×1, No.11–No.18 |
| Thread Configuration | 4-thread overlock, firm edge sealing | 4-thread overlock, firm edge sealing |
| Core Functions | Auto thread trimmer, auto presser foot lift, differential feed | Auto thread trimmer, auto presser foot lift, differential feed |
| Drive System | Direct drive servo motor, silent energy-saving | Direct drive servo motor, silent energy-saving |
| Control Panel | Digital operation panel | Digital operation panel |
| Applicable Materials | Shoe upper lining, reinforcement fabric, synthetic leather, mesh, interlining | Thick lining, multi-layer reinforcement, leather edge, webbing trim |
| Presser Foot Lift | 5 mm manual / 10 mm pneumatic | 6 mm manual / 12 mm pneumatic |
| Working Power | 0.55 KW | 0.75 KW |
| Working Voltage | AC220V 50Hz | AC220V 50Hz |
| Machine Size (L×W×H) | 1200×600×1150mm (with stand & table) | 1200×600×1180mm (with stand & table) |
| Wooden Box Size (L×W×H) | 1280×680×1250mm | 1280×680×1280mm |
| Net Weight | 70 KG | 80 KG |
| Gross Weight | 90 KG | 105 KG |
Application Fields
Operation Guidance
- Check power supply, needle condition and thread threading before startup
- Adjust stitch length, differential feed ratio and thread tension according to material
- Test sew on small material sample to confirm edge effect before formal production
- Place lining cut piece flat under presser foot, control pedal to complete automatic overlocking
- Clean thread scraps and dust on machine surface, cut off power after daily work
Installation Guidance
- Place the machine stand on flat solid ground, fix table board stably
- Connect AC220V power supply with reliable grounding wire
- Install needle, thread stand and auxiliary accessories following operation manual
- Run 3–5 minutes no-load test, finish stitch tension debugging with sample shoe materials
Maintenance & Repair InstructionsDaily Maintenance
Clean surface thread scraps and dust; lubricate needle bar and rotary hook, check thread passing path
Weekly Maintenance
Inspect feed dog and needle plate wear, tighten loose screws and test thread break detection function
Monthly Maintenance
Deep clean internal thread accumulation, check motor belt tension and replace severely worn parts timely
Repair Rules
Solve faults according to touch screen error prompts; cut off power before disassembly; replace worn rotary hook and needle regularly to guarantee stitching quality


