The zipper is a very common trimming used in clothing. It is used to lose all kinds of garments, from a jacket to a trouser , a skirt, a shirt, etc… And because it is such a used trimming, it is good to know the 8 key points for checking the quality for the zipper.
Regardless of the type of zipper, metal , coil or vision, we can make the following checks.
Lateral Resistance
This test measure the strength of the zipper tape. The lateral resistance os taken on about 2.5cmof the zipper tape. At 90 degrees of the elements of the zipper and on both sides pressure at the same time. This check is about determining the strength of the ordincary zipper. Method: With the zipper closed, a pressure is applied at a right angle to the belt in both directions.
Lateral resistance of the bottom stop
The resistance of the bottom stop of the closed or open zipper is checked. It is taken on the tape at the height of the zipper stops. A pressure is applied at 90 degrees form the stop on both sides.
Slider holding capacity
For check the slider resistance. Hold the zipper at the bottom, pull the slider and drag to the top stop . The fixing resistance is measured by pulling the handle firmly.
Holding capacity of the lower area
The strength of the lower stop and the elements of the zipper are checked. Drag the slider down to the lower stop opening the teeth in opposite directions.
Lock slider capability
In this case, the resistance capacity of the interior blocking elements of the slider is measured. Slide the slider towards the centre of the zipper opening the rest towards the ends.
Puller Resistance
The puller capacity is measures by applying a force at 90 degree and 45 degree angles with respect to the slider.
Element Resitance
To check the resistance of the zipper teeth. It is done by applying a force at 90 degree of the tooth of the rack.
The REACH legislation of the European Community that affects the chemical substances related to the zippers are
- Lead
- Heavy Metals
- Nickel
- Phthalate
- Azos dyes
In Addition, the zipper must be resistant to the corrosion and be free of burrs and edges.
The size of the zipper
Finally take into account the weight of the fabric when choosing the size of the zipper. It is not consistent to use a big size zipper on a thin fabric or vice versa.
| FABRIC TYPE | FABRIC WEIGHT | PREFERRED ELEMENT WITH |
| Ultra light | 85-120 gr. | 2.5-4.0 mm. |
| Light | 120-160 gr. | 4.0-5.5 mm. |
| Average weight | 160-24- gr. | 5.5-7.0 mm. |
| Medium- high weight | 240-320 gr. | 7.0-8.5 mm. |
| Thickness | 320-410 gr. | 8.5-12.0mm |
Taking into account that according to the type of zipper the mesh has one measure or another
| #3 | #4 | #5 | #8 | #10 | |
| Nylon | 4.1mm | 5.1mm | 6.5mm | 7.1mm | 10.2mm |
| Polyamide | 4.6mm | 4.9mm | 5.8mm | 7.7mm | 8.5mm |
| Iron | 4.5mm | 4.9mm | 5.9mm | 8.5mm | 8.9mm |
As we said, the zipper is a trimming with a complex structure. Therefore, it is appropriate verify its quality before deciding to use one or other. A few simple checks can avoid serious problems in both production and service to our customers