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JACK® C5T-4-M03 overlock industrial sewing machine

JACK · Overlock

JACK® C5T‑4‑M03

JACK® C5T-4-M03/333 – 4-Thread Digital Overlock with Top Feed Double Transport, Automatic Chain Cutter & Photocell Auto Foot Lifter – Complete Setup, Table & Stand Included

$2,545

In stock

The JACK® C5T-4-M03/333 is a fully automatic 4-thread digital overlock built around one thing the standard serger cannot do: top feed .

  • Free shipping to most US states
  • Financing — Affirm & Synchrony
  • Manufacturer warranty
  • Genuine parts & US service
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Add to cart, then check out securely. Financing (Affirm & Synchrony) applied at checkout.

Performance

Stitch Type
Overlock — plain seam mock safety stitch
Max Stitch Length
4.6 mm
Max Sewing Speed
6,000 SPM

Capacity

Number of Needles
2
Needle System
DC×27 #11
Needle Distance
2 mm
Presser Foot Lift
5.5 mm
Presser Foot Lifter
Automatic electronic (photocell)

Automation

Thread Trimmer
Automatic electronic chain cutter (photocell)
Lubrication
Automatic

Physical

Brand
JACK
Model
C5T-4-M03/333
Machine Type
4-Thread Digital Overlock / Serger with Top Feed
Application
Medium / Light — Knitwear
Number of Threads
4
Stitch Width (Overedging)
4 mm
Differential Feed Ratio
0.7 – 2.0
Feed Type
Double transport — lower feed dog + top feed
Construction
Flatbed
Motor
Direct Drive Integrated Servo Motor
Thread Cut Length
8 mm front / 5 mm back
Operating Modes
Manual · Semi-Automatic · Fully Automatic
Connectivity
Built-in WiFi module (Industry 4.0)
Voltage
110V
Head Dimensions
505 × 360 × 565 mm
Net / Gross Weight
29.2 kg / 39.8 kg
Table Type
Fully Submerged Industrial Table
Assembly
Ships Assembled — Table & Stand Included

Manufactured by

Jack. 30+ years of industrial sewing.

350+ genuine parts in stock (USA) · authorized US service · manufacturer warranty included.

More Overlock

Detail

How it runs on the floor

The JACK® C5T-4-M03/333 is a fully automatic 4-thread digital overlock built around one thing the standard serger cannot do: top feed. A powered upper transport works together with the lower feed dog, so both layers of fabric advance at the same rate instead of the top layer creeping backward against the bottom one. An adjustment gear sets the differential ratio between the upper and lower feed, which means slippery knits, stretch panels, and mismatched-length seams stay aligned from the first stitch to the last — no operator stretching, no re-cutting the seam.

Read more

Beyond the feeding system, this is a full-function automatic machine: photocells drive an electronic chain cutter and an electronic presser foot lifter, and the operator can run it in three modes — fully manual on the pedal, semi-automatic where the pedal sews while the machine trims and lifts on its own, or fully automatic where the photocells run the entire cycle. Set up for medium and light knitwear with DC×27 #11 needles and a 4 mm overedge, it runs at 6,000 SPM on a direct drive integrated servo.

What's Included

  • JACK C5T-4-M03/333 4-thread top feed overlock machine head (ships assembled)
  • Fully submerged industrial sewing table
  • Industrial stand with motor mount
  • Direct drive integrated servo motor
  • Photocell sensor assembly (chain cutter + foot lifter control)
  • LED work lamp
  • Standard accessories kit
  • Instruction manual

Key Features

  • Top feed double transport — a powered upper feed works with the lower feed dog so the top and bottom plies advance together, eliminating the layer shift that ruins knit and stretch seams
  • Adjustable upper/lower differential gear — the ratio between top and bottom feed is set by an adjustment gear, so the machine can be dialed in per fabric instead of fighting it at the operator's hands
  • Three sewing modes — manual (full pedal control), semi-automatic (pedal sews while trimming and foot lift run automatically), and fully automatic (photocells run the complete cycle)
  • Automatic chain cutter — photocell-triggered electronic trimmer cuts the thread chain at the start and/or the end of the seam, with no manual chain handling
  • Automatic presser foot lifter — electronically controlled, lifting before and/or after sewing under photocell command
  • Short thread cut — 8 mm at the front and 5 mm at the back, so garments come off the machine needing little or no thread cleanup
  • Fast acceleration and braking — 0 to 5,500 rpm in 100 ms and 5,500 rpm to 0 in 180 ms, a 14.3% response improvement that pays off on short seams and high piece counts
  • Mesh fabric mode — prevents false starts when tulle, organza, or other sheer material lets light through the photocells
  • Voice guide — spoken walkthrough of machine functions and of error causes and fixes, accessed from the VOICE button
  • Industry 4.0 WiFi module — built in, for adjusting parameters and monitoring productivity from the app (a Jack gateway is required for every 50 machines)
  • 6,000 SPM top speed with a 0.7–2.0 differential ratio range for gathering and easing as well as flat sewing
  • Automatic lubrication — continuous oil delivery for sustained high-speed production running

Ideal For

  • Knitwear production — T-shirts, polos, sweatshirts, and jersey garments where the top ply tends to slip
  • Activewear and stretch fabric lines requiring aligned seams across elastic panels
  • Lingerie, sleepwear, and lightweight apparel on slippery synthetics
  • Sheer and mesh work — tulle, organza, and voile, using mesh fabric mode
  • Serging operations where seams of unequal length must be eased together without operator stretching
  • High piece-count production lines where automatic trim and foot lift remove seconds from every cycle
  • Factories standardizing on Industry 4.0 machine monitoring
  • Shops upgrading from a conventional bottom-feed-only overlock

Questions

Before you buy

Quick answers to the questions buyers ask most about Jack industrial machines. For pricing, configuration, and live availability, the Shopify product page is always the source of truth.

How do I get current pricing for this Jack model?

The price is shown above on this page. Add the machine to your cart and check out securely — the current price, configuration options, financing (Affirm & Synchrony), and delivery estimates are confirmed at checkout.

Does the machine ship as a complete setup?

Most Jack industrial models ship as complete production setups: head, servo motor, table, and stand. The product description above lists exactly what's included for this specific model.

What kind of warranty does Jack provide?

Every Jack machine carries a manufacturer warranty against defects in materials and workmanship. Authorized US dealers also provide local service and parts support. See the Shopify product page for the warranty terms specific to this model.

Are genuine Jack replacement parts available?

Yes. Original Jack feed dogs, hooks, gauge sets, presser feet, and electronics are stocked and traceable to the manufacturer. The Service & Parts page lists parts categories; the Shopify store carries the active SKUs.

Where is service available in the United States?

Authorized service technicians work nationwide through Jack's US dealer network. The Service & Parts page explains how coverage works, and each model's Shopify listing routes you to the dealer closest to your production floor.

Other Overlock machines

JACK® C5T‑4‑M03

$2,545