Metal Zipper Making Machine Guide: Process & Line

Metal zippers are the strong, premium-looking zippers used on jeans, jackets, workwear and bags. Making them is different from making nylon or resin zippers — the teeth are formed from metal wire, and open-end metal zippers need extra machines. Here is how a metal zipper line works, machine by machine, from Jeso (Primo Zipper Group), a 40-year zipper machinery factory.

How metal zippers differ from nylon and resin

All zippers share a finishing section, but the way the teeth are made is what separates the three materials:

For the full comparison see nylon vs metal vs plastic zipper machines.

The metal zipper line, step by step

1. Tape weaving

As with every zipper, it starts with the woven tape. The tape size and cord edge are matched to the metal zipper size (for example #3, #5, #8, #10) so the formed teeth clamp on cleanly and evenly.

2. Teeth forming — the defining step

A teeth-forming machine shapes each tooth from a continuous metal wire and clamps it onto the tape edge at a precise pitch. The wire material sets the look and feel — bright brass, aluminium, or an antique/oxidised finish. Even spacing and firm clamping here decide how smooth and strong the finished zipper will be.

3. Gapping

A gapping machine removes teeth at set intervals to create the spaces where the slider and stops will sit and where each finished zipper begins and ends. Accurate gapping fixes the finished length and keeps every later step aligned.

4. For open-end zippers: hole punching + pin & box

Open-end (separating) metal zippers — the kind on jackets — split fully apart, so they need an insertion pin & box at the base instead of a fixed bottom stop. That requires two extra machines: a hole-punching machine that punches the locating holes, and a pin & box machine that fits the metal pin and retainer box.

5. Slider / head mounting

A head-mounting machine fits the complete slider onto the chain. A direct in-line feeder suits common slider pulls; a side-feed machine handles fancy or irregularly shaped pulls.

6. Metal top and bottom stops

Stops keep the slider on the zipper. For metal zippers:

• Top stops are fixed with aluminium wire (or a U-shaped pre-made top stop).
• Bottom stops (closed-end zippers) are applied with aluminium wire, or as an H-shaped metal bottom stop — the heavy "staple" type commonly used on metal zippers.
• Open-end zippers use the pin & box from step 4 instead of a bottom stop.

7. Cutting

A cutting machine cuts the chain into finished zippers at the gapped points — separate cutters are used for open-end and closed-end zippers, and ultrasonic cutting adds extra precision for higher-spec work.

8. Quality testing

Finished zippers are tested for pull strength, open/close endurance and slider smoothness before packing, so problems are caught in the factory rather than by your customer.

Planning a metal zipper line

Two practical notes for buyers:

• Decide open-end vs closed-end early. If you will make jacket (open-end) zippers, budget for the hole-punching and pin & box machines from the start.
• Reuse your finishing section. If you already run a nylon or resin line, much of the finishing equipment and operator skill transfers — adding metal is mostly the teeth-forming and metal-stop machines.

Because the machines must work as a matched set, buying the line from one factory-direct supplier keeps everything aligned and gives you one point of contact for installation, training and spare parts. See also how to start a zipper factory.

Jeso is the zipper-machinery brand of Primo Zipper Group, a Wenzhou, China factory established 1984. Process steps are described in general terms; exact machine models and sequence are configured to each customer's products and output.