Twin Needle Direct Drive Lock Stitcher

T-8421D Basic function

  • t8421d

T-8421D - Twin Needle Direct Drive Lock Stitcher

・User- intuitive color LCD display touch panel
・Productivity improvement with IoT capabilities
・Equipped with needle breakage prevention function while reverse sewing
・USB port on operation panel

Further Progress Based on Reliability

Equipped with the Color LCD touch panel, the functionality becomes easier to use. The needle breakage prevention function which prevents the needle breakage when reverse stitching is carried out with the quick back switch. This contributes to the improvement of the operator's work efficiency.

User- intuitive Color LCD Display Touch Panel

The Color LCD display touch panel display items with illustration icons, offering easy user-intuitive operation. There are three types of operator panel display. All the detailed home screen, quick home screen and easy home screen are easy to use without concern for panel operation.

Detail home screen

Quick home screen

Easy home screen

Equipped with needle breakage prevention function while reverse sewing

We thoroughly investigated the cause of the needle breakage and needle point crushing problem that frequently occur in thick fabric backstitching and equipped this model with the function to prevent needle breakage. In addition, the quick back switch is located at a position where the operator can easily press, contributing to improved productivity.

Reliable sewing with strong needle penetration

Powerful 550W motor outputs large amounts of torque even at slow speeds so that strong needle penetration force can be obtained. This allows accurate sewing of heavy materials and joints. If the needle penetration resistance increases when sewing heavy materials and materials with joints, vibration control (intermittent impact) automatically increases the penetration force. (Patent pending)

In-house development improves control board reliability furthermore.

We adopted the control circuit board design which has been proven effective in other models and strengthened the ability to cope with the voltage fluctuations. In addition, vibration resistance is improved, and you can use it safely in various environments.

Reduce downtime with easy gauge replacement

Cam adopted in the lateral position adjustment mechanism for the rotary hook base allows easy fine adjustments for clearance between the needle and rotary hook point can easily be made. This greatly increases the efficiency of replacing gauge parts. Furthermore, a needle drop correction function (sideways) is provided, so that the needle drop position can still be adjusted to the center of the needle hole even if using commercially-available gauge parts. The gauge parts for previous models can still be used without any changes.

Improve sewing quality by feeding method according to the process

A function to switch between needle feed and lower feed is equipped as a standard function. Needle feed is effective in preventing uneven material feeding, and lower feed prevents puckering and is ideal for making quick and frequent turns. The operator can select the optimum feed method according to the material and the process, so that sewing quality can be increased.

USB port on operation panel

The Display panel is equipped with a USB port so sewing patterns and various environmental settings can be copied and shared easily with other sewing machines of the same function. This also permits software upgrades to be performed using the USB media.

Productivity improvement with loT capabilities

This model is loT applicable. The visualization by connecting sewing machine and computer technology enables the customer to analyze, manage processes and speed up productivity improvement and maintenance work. *It is applicable for Brother’s IoT system. For more information, please refer to the catalog of “Brother Industrial Sewing Machine Network System”.


Twin Needle Lock Stitch Sewing Machine Lineup


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