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SAFE · Overlock

SF-TK7-4ATDifferential-Feed Stepper Overlock Machine

The SF-TK7-4AT is a four-thread differential-feed overlock sewing machine. An additional upper feed dog in front of the needle assists handling of layered fabric that may slip or stretch during garment sewing.

Compare this model with overlock machines, or use our machine selection enquiry guide to prepare your requirements.

MOQ: 1 machine1-year warrantyRemote support
SAFE SF-TK7-4AT Differential-Feed Stepper Overlock MachineSAFE catalogue product image

Product advantages

Details that support the operation.

  • 01Additional upper feed helps coordinate the movement of fabric layers.
  • 02Differential feed adjustment supports materials with different stretch characteristics.
  • 03Two-needle, four-thread overlock configuration.
  • 04Maximum listed speed of 7,000 rpm; choose the operating speed to suit the material and seam.
Illustration of materials or applications relevant to SF-TK7-4AT
Application illustration. Not a specific machine’s sewing test or output.

Applications & sewing operations

Review it against your production task.

  • Overlocking and lap seams in garment and underwear production.
  • Layered materials with different stretch or surface friction.
  • Pattern matching and decorative garment seams, subject to sample review.

Send your material and intended seam for configuration review. Optional functions and attachments should be confirmed in the quotation.

From the SAFE catalogue

A closer look.

Technical data

Specifications.

Specifications follow the reviewed SAFE v06 catalogue. Confirm your final machine configuration in the quotation.

SpecificationDetails
Needle typeDC×27 #9
Needles / threads2 / 4
Needle gauge3.5 mm
Overedge width3–5 mm
Stitch length3.2 mm
Presser-foot lift5.5 mm
Differential feed ratio1.1–3.8
Maximum speed7,000 rpm
Packing dimensions472 × 495 × 360 mm
Net / gross weight28.5 / 37 kg

Before you choose

Questions about this machine.

What is the extra upper feed used for?

It assists the movement of the upper fabric layer. It is useful to discuss when layers slip, stretch differently or need pattern alignment.

What should I test on a 4-thread overlock machine?

Review the finished overedge seam, stretching or gathering, layer alignment and thicker crossings using the intended fabric. Check the feed settings, seam width and needle/thread configuration together before confirming the production setup.

Ordering & after-sales

Support beyond the machine.

Tell us where the machine will be used and the configuration you require.

From one machineOrders for factories and dealers
1-year warrantyMachine warranty and spare parts supply
Remote technical supportShare model, issue and a short video
Pakistan officesKarachi and Faisalabad contacts

Continue your machine selection

Related equipment and operations.

Compare the handling method and finished seam. These machines cover different configurations or neighbouring production steps; confirm the right choice against your sample.

Discuss your SF-TK7-4AT.

Share your material, seam photo and quantity with Trentzhou.

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