JACK® S7-91T - Single Needle Post-Bed Triple Feed Industrial Lockstitch Sewing Machine – Complete with Table & Stand

Single Needle • Post-Bed • Triple Feed • Independent Dual Roller Feed • Needle Feed • 4-Motor System • Automatic Thread Trimmer • 5" Touch Screen

At JMJ Sewing Machines, we recommend the JACK® S7-91T for experienced operators working with shaped leather and textile assemblies. This single-needle post-bed lockstitch machine combines adjustable roller transport, needle feed, and electronic controls for detailed production work.

For workshops sewing shoe components, shaped bags, or patches on structured caps, the raised post provides working access around contours. JMJ recommends checking the shape and thickness of your actual materials before choosing this specialized setup.

The upper roller, lower roller, and needle feed work together to move material through the stitching area. Operators can adjust the roller relationship to suit curved seams and transitions between layers.

Triple Feed System

Independent Dual Roller Feed

Each roller has independent electronic control. The differential settings let the operator fine-tune how material advances on either side of a shaped seam.

JMJ recommends testing a sample of the actual shoe, cap, or bag construction to establish the most suitable roller settings.

4-Motor Intelligent Drive System

Post-Bed Design for 3D Sewing

Unlike a conventional flat-bed machine, the S7-91T uses an elevated cylindrical post that allows shaped products to be positioned around the sewing area.

This provides excellent access to curved and difficult areas when sewing cap crowns, shoe uppers, handbag interiors, glove sections, leather accessories, and upholstery components.

Excellent for Patches on Caps & Hats

5-Inch Multilanguage Touch Screen

The integrated 5-inch touch screen provides convenient access to machine settings and programmable functions. Operators can manage supported parameters such as sewing speed, stitch length, sewing modes, and other machine settings through the digital interface.

The control system also includes multilanguage operation and voice guidance to simplify machine setup and daily use.

Programmable Stitch Length

A programmable stitch key allows the operator to switch quickly between different stitch lengths during sewing. This is particularly useful for decorative work and applications where different seam sections require different stitch specifications.

Ornamental Stitch Patterns

The S7-91T can be programmed to combine different stitch lengths and repetitions, allowing the operator to create ornamental and decorative stitch patterns for footwear, leather goods, handbags, and other visible seam applications.

High Penetration Capacity

The machine is engineered for demanding materials and high penetration requirements. The specified penetration capability exceeds 110 layers of A4 paper, demonstrating the machine's ability to handle thick assemblies and demanding materials used in work shoes, leather goods, and heavy industrial products.

Automatic 3 mm Short Thread Trim

The integrated automatic thread trimming system is designed to leave an approximately 3 mm short thread tail after cutting, reducing the need for manual thread trimming and providing a cleaner finished product.

Silent Stepper-Motor Bartack

The automatic bartacking system is controlled by a stepper motor, providing quieter and faster seam reinforcement compared with traditional mechanical bartack systems.

Adjustable Roller Pressure

Roller pressure can be adjusted conveniently using the control located on top of the machine. This allows the operator to adapt material pressure according to different thicknesses and sewing applications.

Extendable Double-Layer Bartack Lever

The machine incorporates an extendable double-layer bartack lever designed to provide convenient manual control during sewing. The second layer can be extended when required for easier operator access.

Self-Cooling Handwheel

The fan-style self-cooling handwheel is designed to improve airflow around internal components. According to the specified configuration, the system can help reduce internal operating temperature by approximately 4°C, supporting machine durability during extended production.

LED + Ultraviolet Work Light

The S7-91T incorporates adjustable LED illumination with multiple intensity levels together with an ultraviolet light system. The lighting system improves visibility around the needle and seam area, particularly when working with dark materials and detailed sewing lines.

Swing Edge Guide

The integrated swing guide helps maintain a consistent seam distance during sewing. It is particularly useful when following edges around curves and changing material thicknesses where maintaining uniform seam placement is important.

Variable Speed — 100 to 3,000 SPM

The electronic speed control provides an operating range from approximately 100 to 3,000 stitches per minute. Low-speed operation provides excellent control for detailed decorative work and tight curves, while higher speeds support efficient professional production.

Bevel Gear Hook System

The vertical-axis rotary hook uses a bevel gear drive system designed to reduce mechanical noise and vibration while providing smooth hook operation and consistent lockstitch formation.

Key Features

• Single Needle Post-Bed Lockstitch: Designed for professional three-dimensional sewing applications.
• Triple Feed: Top roller, bottom roller, and needle feed work together for precise material transport.
• Independent Dual Roller Feed: Computerized rollers with programmable differential provide accurate feeding around complex curves.
• 4-Motor System: Main shaft motor plus three independent stepper motors control needle feeding and both rollers.
• High-Torque Direct Drive: Provides responsive beltless power and precise electronic speed control.
• 5-Inch Touch Screen: Multilanguage digital interface with voice guidance.
• Programmable Stitch Length: Quickly switch between different stitch lengths during sewing.
• Ornamental Stitch Programming: Combines different stitch lengths and repetitions for decorative applications.
• Automatic Thread Trimmer: Leaves an approximately 3 mm short thread tail.
• Automatic Presser Foot Lifter: Reduces repetitive operator movements.
• Silent Bartack: Stepper-motor-controlled seam reinforcement.
• High Penetration Capacity: Designed for thick leather and demanding heavy-duty materials.
• Adjustable Roller Pressure: Quickly adapts pressure to different material thicknesses.
• Self-Cooling Handwheel: Fan-style design improves airflow around internal components.
• LED + UV Lighting: Adjustable illumination improves seam visibility.
• Swing Edge Guide: Helps maintain consistent seam positioning.
• Variable Speed: Approximately 100–3,000 SPM.
• Bevel Gear Hook: Designed for smoother operation with reduced noise and vibration.

Ideal For

• Footwear Manufacturing: Leather shoes, athletic shoes, work boots, shoe uppers, and heel seams.
• Leather Goods: Handbags, suitcases, briefcases, wallets, belts, straps, and gloves.
• Caps & Hats: Embroidered patches, leather patches, woven labels, and brand tags on snapbacks, trucker hats, fitted caps, and beanies.
• Automotive Upholstery: Car seats and shaped interior components.
• Furniture Upholstery: Sofas, chairs, and heavy vinyl seating.
• Sports Goods: Protective equipment, athletic products, and technical goods.
• Promotional Products: Branded headwear and custom leather products.
• Heavy-Duty Equipment: Pouches, holsters, harnesses, and similar reinforced textile products.

Technical Specifications

JMJ Sewing Machines recommends the JACK® S7-91T for workshops that need controlled stitching around curved leather goods, footwear components, and shaped accessories. Our offering includes the industrial table and stand. Contact our team to confirm the configuration for your intended materials and production requirements.