Zipper Trim Quality Control in Garment Manufacturing- In Garment Export house or you can say in a garment manufacturing factory , where every stitch tells a story, the zipper stands out as a silent but crucial center figure . Zippers may seem small, but they’re a big deal. Imagine your favorite jacket without a zipper – not so great, right?
Quality controllers and assurance professionals play a pivotal role in ensuring that this small yet important component meets exacting standards. Let’s understand the complexities of zipper quality control, understanding the implications that make it an art form in garment creation..
Zipper Trim Quality Control in Garment Manufacturing Contents
Zippers should be checked for :
1. Dimensions. Zippers need to be just the right size, check for the correct width of tape. if it’s too big or too small, it can mess up & the machine will run off. Measure overall length with the zipper closed from extreme ends of metal. Tape extensions should be as specified.
2. Stopper – Top and bottom stops should be fastened securely so that the puller wont go anywhere .
3. Color – Zipper tape should be uniform in color if that is important. Quality controllers check that the color of the zipper tape is the same all over. Nobody wants a zipper that’s two shades of black and should be matching to the Approved Standard.
4. No Wrinkles Allowed: Keeping It Smooth – Zippers should slide into clothes like they belong there. Quality checks make sure they don’t cause any wrinkles or weird bumps. Because who wants a lumpy zipper ruining a perfectly good outfit?
5. Durability against Washing –Check for the durability of zippers under various laundering methods, assessing fading, and evaluating resilience under pressing or ironing for a garment .
6.Pull Strength Analysis – Beyond routine checks, scrutinizing the pounds required to pull open the zipper sideways becomes a resilience indicator, ensuring usability and reliability
7. Pull Tab Affixation – Careful examination of pull tab affixation to the slider body ensures smooth and reliable zipper operation, emphasizing the importance of every component.
8.Balancing Act – slider should be riding freely while maintaining a secure grip on the chain—is a testament to quality craftsmanship and user satisfaction.
9. Security Check: Ensuring Slider Locks – A critical element in preventing accidental openings and potential garment mishaps, it should be doubled checked safeguarding both the product and the wearer.
Common Causes of Zipper Failures:
- Improper Installation Methods in the Sewing Room:
- QA or QC must check the sewing room practices to ensure that the installation of zippers aligns with the highest standards. Deviations from correct procedures can lead to a cascade of issues.
- Questionable Garment Design or Construction:
- Collaborating closely with design and technical teams, QA need to evaluate the garment design for its compatibility with zipper integration. Any flaws in the design can contribute to long-term zipper challenges.
- Incorrect Product Application:
- Ensuring the right type of zipper for a specific garment application is paramount. QA teams play a crucial role in validating that the selected zippers align with the intended use, preventing compatibility issues.
- Factory and/or Retail Customer Abuse:
- Beyond the manufacturing stage, zippers can face harsh treatment during transportation, handling, and retail processes. QA measures should extend to these phases, ensuring the durability of zippers against external stressors.
The zipper, though a mechanically operational device, is exceptionally vulnerable to human error. This vulnerability amplifies, especially in factories employing continuous zipper chains, where gapping, bottom stopping, and slidering operations occur in-house. QA and QC professionals are the first line of defense against these vulnerabilities, recognizing that even the smallest error in these intricate processes can lead to significant consequences.
This informational guide serves a dual purpose – to identify and address the most common causes of zipper failures at the plant level and to offer tailored insights for continuous chain users. QA and QC teams are directed towards these common pitfalls, armed with the knowledge to detect and rectify issues in real-time. The goal is to empower continuous chain users with the tools to ensure the flawless integration of zippers, preventing problems before they manifest in the final product.
Slider Direction
The slider must run in a specific direction. On metal chain, the points of the teeth must face towards the open end of the zipper) Correct direction is more difficult to determine with plastic chain, but in both cases, arrows are usually printed on the tapes that point towards the top, open end.
Right Side Up
On plastic coil and extruded tooth chain, the slider should be mounted, with the pull! tab on the same side as the printing on the tapes. Some coil zipper is not symmetrical, therefore making slider mounting obvious. Side to side orientation is not critical with metal or molded chain.
Stabilization
Most zipper tapes contain some percentage of cotton, or cotton-blend yarns in order to provide a dense anti sleazy construction. A resin treatment option is available for permanent press or low shrink applications, which is commonly referred to as stabilization. This process consists of applying a material to the chain which, when cured with a specified temperature/tune relationship, will impart synthetic qualities te the cotton, at some sacrifice of strength.
Resin treated chain is available in either a semi-cured or fully-cured state, to match similarly treated textiles. The use of fully- cured chain with serni-cured textile will result in tape degradation when the assembly is subjected to a final cure. Also, the use of resin treated chain in a garment that receives resin treatment as an assembly, will subject the tape to double treatment, resulting in degradation of the cotton yarns.
Slider and Chain Combinations
Every zipper manufacturer has a large stable of slider and chain available for most applications. Materials vary front lightweight plastic through the family of metals such as zinc, steel, brass, and nickel-silver. Slider action covers a spectrum from nonlock. pinlock, camlock, flingelock, fliplock and autolock, Selecting the proper combination is best left to application fib of the zipper supplier.
Handling and Processing Zipper
zipper chain should be stored at a moderate temperature and humidity. Long term storage at elevated tempertures can cause me tape yarn deterioration, especially with resin treatment.
Inspection
Excessive tension or shock loading of zipper chain during processing can affect dimensions angy cause latent shrinkage Running more than one manufacturer’s chain simultaneously can result in accidental mixing of components.
Ratcheting
This is the act of forcing the slider down the chain by pulling the two open halves apart. Although some sliders are designed to ratchet, this action does damage. degrades the teeth, and with positive locking sliders the chain is destroyed. Ratcheting occurs in the sewing room, finishing, and at industrial laundries when the operator wants to open the garment fast. Retail users can ratchet a slider by not fully opening the zipper when putting on cor removing the garncut, or as a deliberate act to allow return of an unwanted item..
Shear
This is the act of attempting to shift one half of the chain with respect to the other half after the slider is mounted. It occurs when an operator tries to adjust the waistband alignment without first removing the slider, and usually results in permanent damage.
Slider Distortion
A slider is “clam shelled” when the top and bottom have been spread apart, as in opening a clam. This condition can be caused by a sticking slider holder or by an over-zealous consumer trying to move a stuck slider with a pair of pliers. A crushed slider usually occurs in the pressing buck of the garment factory or industrial laundry.
Slider Holder
This device holds the slider by the pull tatt, and lifts the lock out of the path of the chain during slider threading. A misadjusted holder can can ratcheting of the lock release malfunction, or clam shelled siders and chain damage if the pull clump docs not release after threading.
Bottom Stop
The primary function of the bottom stop is to prevent accidental opening of the closed end of the chain. A stop that is not tightly clinched over the zipper teeth, of is totally missing will allow the chain to open behind the slider. This condition can sometimes be repaired in the factory by pulling the slider down, thus rehealing the chain, and applying a new stop.
Sewing
The major cause of zipper failure is poor sewing. A garment panel attached too close to the teeth will interfere with the slider and get caught inside. Attempting to free the slider can cause garment and chain damage, or clam shelled sliders. A sew line that is not parallel to the chain or wanders, causes localized high stresses and curvature, which can eventually lead to erratic slider action and tape failure. Low stitch count can lead to tape sleaziness, and using blunt, larges diameter needle will cause heating and melting during sewing because of the high density tight weave inherent in zipper tapes, Improper tread trimming will cause interference with slider action when the loose ends become caught.
Fly Serging
The outer cige of zipper tape can be accidentally cut during right fly serging by the serging knives, causing disasterous zipper failure. The best police is so remove the knives entirely, or use a positive edge guide.
Hump
Hump is a roller coaster effect of either the zipper chain or garment at the sew line. A humpy zipper is usually caused by the operator over-tensioning the garment pane! during sewing, on leading the assembly, with the chain down in engagement with the feed Jog. A lumpy garment is usually causal by tensioning the zipper during sewing, or excessive foot pressure. Hung after washing or dry cleaning is the result of excessive differential shrinkage between the garnsent and zipper. Contrary to popular opinion, this condition is usually the result of excessive garment textile shrinkage. resulting in zipper hump.
Popping
A zipper that opens in one spot has been “popped”. This can be caused by a very high localized force, but is usually the result of folding the zipper back upon itself tightly while under cross-wise load. Most metal and extruded or molded plastic chain is almost impossible to “pop.” Coil zipper “pops” more readily, but can be “healed” by running the slider down and back up.
Waistband and Hook/Eye Closures
The hook and bar, snap, hook and eye, and button closures used at the top of the zipper opening are intended to absorb all of of the crosswise stress when closed. Mislocated or poorly attached closures will subject the zipper teeth to very high stresses at the top Garments that are sized small, or retail customers that purchase undersized items. promote failure because these closures are usually left open and the slider is used to keep the opening closed.
Waistband and Bottom Sewing
An area that merits special attention is the sew line that runs across the zipper at the waist-band. Normally, it is possible to sew directly across most plastic chain with no needle damage, eliminating the need for top stops. Metal chain needs to be gapped in the area where the line crosses, ether by removing all the teeth from that point up to the end, or by removing only a few teeth at the line (needle grating). If top stops are not used on metal chain, it is important to assure that none of the gap project below the waistband, otherwise the slider will come all The bottem zipper extensions should be firmly sewn down completely to their ends. to impart longitudinal stability. Inadequate bottom sewing causes the slider to snag on the teeth during closing.
Chemical Degradation
The largest cause of long term zipper failure at the retail level is repeated laundering in overly harsh agents. The faded jean craze is probably the number one problem. Staking the garment in a high concentration bleach solution and subjecting it repeatedly to harsh low phosphate detergents will corrode brass chain and sliders, and harden the teeth of plastic zippers. This condition has lately been accentuated by prewashing garments in industrial laundries prior to sale. Some retail customers return garment for zipper failure in which the scams are open and the textile yarns are broken because of severe chemical degradation.
Bar Tacks
Bar tacks serve the function of protecting the bottom stop from excessive load in fly applications. A missing bar tack, or one set too low, could result in a bottom stop failure at the retail level.
Design Problems
Many potential zipper problems can be avoided at the garment design level. Some of the more common errors are:
1.opening too short, causing bottom stop failure, such as in hip tugged jeans
2.wrong size zipper not designed for stress
3.wrong type zipper
4. installation across a heavy fell seam, causing popping and slider snagging
5.insuffrent fly piece reinforcement
6.improper sow line panon, either ion near the suster tape edge or the teeth
7.lack of bar tacks of bottom, as previously mentioned.
