Pre-Production, Production and Post-Production Process in Garment Industry
The process of converting fabrics into garments
Garment production is an organized activity consisting of sequential processes such as laying, marking, cutting, stitching, checking, finishing, pressing, and packaging. This is a process of converting raw materials into finished products. It will be difficult to maintain the industry if production is not, up to the mark if the preproduction phase of preparation of material is not properly carried out.
Ready-to-wear apparel or garment manufacturing involves many processing steps, beginning with the idea or design concept and ending with a finished product. The apparel manufacturing process involves Product Design, Fabric Selection, and Inspection, Patternmaking, Grading, Marking, Spreading, Cutting, Bundling, Sewing, Pressing or Folding, Finishing, and Detailing, Dyeing, and Washing, QC, etc.
Apparel production, also known as garment production is the process of converting fabric into garments. The term apparel production is usually used when garments are manufactured in a factory. Traditionally, apparel manufacturing factories have been divided into two sectors: domestic and export. Based on the present apparel industry, garment manufacturing processes are categorized as:
- Pre-Production processes: The processes that are done prior to the start of bulk garment production are known as the pre-production processes.
- Production processes: In the production stage, the main activity is sewing.
- Post-production processes: In the post-production stages, important activities include finishing and packing.
Development of fabric sample, bit loom, print, and embroidery artwork :
- The fabric is developed as per the buyer’s requirement. Fabric development means sourcing customer-specific fabric with matching properties, dyed and finished for solid colors. For the solid color, lap dip approval is a very important process. Until the lap dip sample is approved merchants re-submit lap dips.
- In the case of yarn-dyed fabrics, merchants develop fabric samples with specified designs, stripes, or checks. These fabric samples are called Bit Loom. Other approvals such as print and embroidery artwork approval and color approval are done. It may be done at a later stage at the time of pre-production.
Costing of a garment (complete cost as well as manufacturing cost) :
- Merchants prepare a cost sheet with details of cost break up such as raw material cost, manufacturing cost, overheads, and margin. Costing is very a critical stage.
- Because whether a company will get an order or not depends on their cost. If the garment cost is very high then the manufacturer may lose the order and on the other hand, if the factory keeps their cost low, they will not earn profit from the order. Estimation of the garment cost should be done on a data-based.
Pattern making, correction of pattern, pattern grading
- In a factory, a pattern master prepares the first fit pattern. Then re-develop the pattern adding buyer comments and rectification on a fit sample. After fit approval, pattern master grade pattern for size set samples only for specified sizes. Once the order is ready for production they grade the pattern for the whole size range.
Fit sample, size set sample making, and approval from the buyer
- Each sample has a certain purpose. Samples are made in the sampling department and sent to the buyer for approval.
- Correction of fit samples according to buyer comments
- If the sample is not approved or further work is recommended by the buyer. Correction is done and re-submitted to the buyer.
- Garment factories receive fabric from overseas textile manufacturers in large bolts with cardboard or plastic center tubes or in piles or bags.
- The fabric typically arrives in steel commercial shipping containers and is unloaded with a forklift. Garment factories often have a warehouse or dedicated area to store fabric between arrival and manufacturing.
- “Relaxing” refers to the process that allows the material to relax and contract prior to being manufactured. This step is necessary because the material is continually under tension throughout the various stages of the textile manufacturing process, including weaving, dyeing, and other finishing processes. The relaxing process allows fabrics to shrink so that further shrinkage during customer use is minimized.
- Garment manufacturers perform the relaxing process either manually or mechanically. Manual fabric relaxing typically entails loading the bolt of fabric on a spinner and manually feeding the material through a piece of equipment that relieves tension in the fabric as it is pulled through. Mechanical fabric relaxing performs this same process in an automated manner.
- Many garment manufacturers will also integrate quality assurance into this process to ensure that the quality of the fabric meets customer standards.
- This step is performed by manually spot-checking each bolt of fabric using a backlit surface to identify manufacturing defects such as color inconsistency or flaws in the material. Fabrics that fail to meet customer standards are returned to the textile manufacturer.
Spreading, Form Layout
After the fabric has been relaxed, it is transferred to the spreading and cutting area of the garment manufacturing facility. The fabric is first to cut into uniform plies and then spread either manually or using a computer-controlled system in preparation for the cutting process. The fabric is spread to:
- Allow operators to identify fabric defects;
- Control the tension and slack of the fabric during cutting; and
- Ensure each ply is accurately aligned on top of the others.
- The number of plies in each spread is dependent on the fabric type, spreading method, cutting equipment, and size of the garment order.
- The spreading process forms a lay by placing one or more fabric plies on top of one another for a required length.
- The length of the lay and the number of plies to be laid for a particular layer will be predetermined as per the cutting plan. It specifies the specifications of each lay type and the number of times the same specification lay has to be cut with different colored fabric plies to achieve the number of garments required in each color and size.
Automated Spreading Machine
- Spreading Equipment consists of spreading surfaces, that is, tables, spreading machines, pins, weight, bars, and fabric control devices as well as fabric cutting devices. Spreading surfaces will depend on the type of fabric, spreading equipment, cutting method, and also the firm’s quality standards. Spreading requires a flat smooth surface. For this purpose, normally a table is used.
- If the table is being used for cutting as well, (in most of the cases it is being used) then it should be leveled. The table must be constructed sturdily, to bear the weight of a spread. The width and length of the table will vary with the width of the fabric and production demands. Most often, the space available determines the dimensions of the table. Spreading surfaces need to be 10” wider than fabric width to allow the cutting knife to rest on the table.
- Spreading tables may have tracks or rails placed along one or both sides or just a few inches off the floor for the spreader to move up and down the length of the table. Spreading tables are usually covered with laminated or corkboard to provide a low level of friction. Special spreading tables may also have vacuum points that are used to compress the lay.
- Lay can be compressed up to 75%. This prevents the movement of slippery fabric and prevents the shifting of fabric during cutting. Air floatation tables allow easy movement of lay when activated.
- Spreading tables may also be connected to a conveyor that carries the fabric to the cutting table.
- A majority of the commercially available spreading tables come as modules. This allows a factory to configure the length as required. A special type of table is used for spreading checked and striped fabrics, which is called pintable.
- Pintables consist of pins beneath the spreading table. The spreading operator can raise the pins at the points where they are required. While laying the fabric the spreading operator pins the fabric down. This allows the fabric to be spread without giving any extra allowance for block cutting. The layers can be cut as per the patterns if the marker is done as per check matching. Spreading machines are of various types. Stationary, portable, or fixed and traveling machines – manual, semi-automatic, and automatic.
- Stationary spreading remains in one position i.e. at the end of the table, while traveling machines move along the length of the table. Manual speeds are the same as operators’ speeds. They basically consist of a frame or carriage, wheels traveling on the tracks, fabric support, and guide rolls to aid correct unrolling of fabric.
Manually Operated Spreaders
- Manually operated spreaders can be as simple as a roll bar mounted on four wheels that is pushed along the table by an operator. In manual spreaders, the spreading speed can be controlled by the operator who moves the machine. The cloth is pulled carefully from the fabric roll by hand and is cut to the appropriate length.
- Mechanical devices can be provided to facilitate the unrolling and cutting operations, but the proper alignment of the fabric edges is the responsibility of the human operator. It is suitable for short lays and for frequent changes in fabrics and colors. It is often used in small businesses.
- The cloth is unwound, and spread semi-automatically, using a manually–driven carriage. The carriage is moved back and forth over the laying-up table. A built-in mechanism takes care of aligning the fabric edges and smoothing the plies. This system is favored when long and broad and/or if the fabric is presented in large batches for relatively large orders. This method is very efficient and suitable for small businesses.
- These machines are therefore ideal for increasing productivity and quality.
- These machines may include various features, such as a motor to drive the carriage, a platform on which the operator rides, a ply cutting device, automatic catchers, ply counters an alignment shifter (edge guides), a turntable, and a direct drive on the fabric support and tension devices.
- Tension mechanisms ensure that the art of spreading is synchronized with the rate of fabric that is unrolled. The alignment shifters are actuated by photo–electric mechanisms since any deviation from the required alignment. In this case, they shift the roll to the correct position.
- End catchers hold the fabric at the end of the lay and overfeed device that feeds extra fabric when a fold is made. Ply cutting devices cut the fabric across the width at the end of the lay. It usually consists of a rotary knife blade mounted on rails.
- Brands: GERBER spreader
A case study on Men's shirt manufacturing in a Garment factory in Bangladesh
- Turntables permit face one-way spreading on every trip. The turntable rotates 180 degrees at the end of the spread. During deadheading, the machine may travel at a higher speed. A very highly automated spreader may be preset to a selected number of plies.
- A sound indicator alerts the user when it has reached the selected number or has come to the end of a piece of fabric. Some machines are equipped with automatic sensing of previously marked flaws and damages. As the machine comes across a flaw, the sensor will halt the spreader, the ply cutter will cut across the ply, and the spreader will reverse direction to the nearest splice mark on the marker plan and then continue its run.
- Laying of paper pattern helps one to plan the placement of the pattern pieces in a tentative manner.
- Lay large pieces first and then fit in the smaller ones
- It is very economical in laying the pattern and cutting. Even a small amount of material saved in a single layer will help to bring about a large saving of money as hundreds of layers of fabric will be laid and cut simultaneously.
- When laying, the length of the garment should be parallel to the selvedge of the material. Be sure the pattern is placed in the correct grain. Fabrics drape and fall better on the lengthwise grain and also last longer.
- Parts that have to be placed on the fold should be exactly on the edge of the fold.
- All laying should be done on the wrong side of the material.
- When laying the paper pattern, consider the design of the fabric. Care should be taken to see that the design runs in the same direction throughout the garment. All checks and strips should match the seams both lengthwise and across.
- This can be a manual or a computerized technique
- The marker planner uses full-size patterns and arranges them in an economical manner on marker paper.
- This is a specially printed paper having symbols on it that enable the marker planner to visually control the positioning of components according to specified grain lines.
- Markers produced on paper are fixed to fabric with pins, staples, or on an adhesive paper which is heat-sealed to the top layer of the fabric.
- Marker planning provides details of the spreads. In the cutting room, the fabric is laid manually or a spreading machine is used to arrange fabric inlays 100 (layers) and markers for the production, any in orders planned. Here planning is done also for fusible, linings, trims, pocketing, etc.
- The supervisors of the marker planner plan and allocate the cut orders to various operations to be carried out in the cutting room.
- In this stage, fabrics are layered on a table layer by layer up to a certain height. Then, using a cutting machine, the fabric is cut into garment shapes or patterns and separated from the layer.
- Cut parts are then numbered, bundled, and sent to the sewing room.
- A cutting department of a garment manufacturing unit includes the following sub-processes: Fabric relaxation, fabric spreading and layering on a cutting table, marker making, cutting – These are of three types: manual cutting (using scissors), machine cutting, and automatic cutting, numbering of garment plies, sorting and bundling, an inspection of cut components, shorting of printing and embroidery panels, re-cutting of panels, fusing garment components.
- Cutting can help save fabric, as well as add value to the quality of a garment. The quality of the end product, (the garment) depends first, on good cutting. Secondly, the main raw material of the garment represents about 70% of the total cost of the garment.
- Cutting can either be manual or automated. Cutting depends on the skill of the operator. This equipment can be portable or stationary. Portable knives are moved through the spread while the stationery cutters require the operator to position and control fabric blocks through the blade. There are two types of portable cutting knives, mainly the vertical reciprocating straight knife and round knife.
- The Straight knife consists of a base plate with rollers for ease of movement, an upright carrying the straight blade, the power system consisting of the motor and switch, the cutting blade which can have various edges, operating handle, sharpening device, and the blade guard. These machines are also available with a blade cooling system.
- The vertical knives have an up and down cutting action. Blades vary in length from 6 to 14”. Blade length and the adjustable height of the blade guard are factors determining the spread height that can be cut. This feature must be considered in choosing a straight knife machine. The blade guard not only acts as a safety device for the operator but also holds the top plies of the fabric, thus preventing them from lifting up during cutting.
- Metal mesh gloves are also available as a safety device for the cutting operators. The cutting blade is available in various edges such as straight, serrated, and wavy-edged. The most commonly used is the straight knife. Wavy edges help to reduce heat generation and are used for cutting plastics and vinyl, whereas, saw edge type is used to cut canvas.
- This machine is most commonly used in the industry today because of its adaptability and flexibility to various kinds of fabrics and spread heights. Due to the shape of the cutting knife, it is a good choice for accurately cutting sharp corners and angles. However, it has its limitations too. It does not give very accurate cuttings along the curves due to the blade shape. The broader the width of the blade, the less accurate the cut along the curves will be. As the machine enters the spread, the base plate lifts up the plies of fabric causing a slight distortion. To overcome this, the edges of the base plate are sloped and the front is curved.
- The base plate is the foundation that supports and helps balance the cutting machine and maintains the position of the blade at 90 degrees. During cutting, it is very important that the machine is not tilted as the cutting would not be proper. The straight knife machine can make only lateral cuts into the spread and cannot be used to cut areas from the center of garment parts.
- Brands: KS-AU, Straight Knife Cloth Cutting Machine
The Supporting Arm in straight knife
- A further advancement to the straight knife machine is the use of a supporting arm that supports the machine from above. Therefore, the heavy base plate can be replaced by a small, flat base plate which reduces distortion of plies, narrower blades, therefore, enabling cutting along sharper curves. Further, there are lesser chances of tilting the blade during cutting.
Rotary or Round Knife
- The Rotary or Round knife is a portable cutting machine. It consists of a round blade, a motor above it, and a handle to direct the machine.
- The knife rotates in the anticlockwise direction. It cuts the fabric with one-way thrust, as compared to the up and down motion of the straight knife. The cutting capacity or spread height depends on the blade diameter, motor power, and speed.
- Brands: Usha Round Knife Cloth Cutting Machine, DE-TECH Round Knife Cutting Machine
End cutters are a special type of round knife machine. A small-diameter round knife is placed on a rail or track with a pushing arm. This ensures an accurate straight cut. End cutters are used to cut the end of the fabric after each spread while spreading.
- Garment parts require notches in order to align them accurately during sewing and assembly. Operator-controlled cutters can be used for this purpose; however, accuracy depends on the skill of the operator.
- It is also necessary that the layer must be absolutely vertical, otherwise, some pieces will be marked too deep while others may not be marked at all. Special notching machines such as straight notchers and vee notchers are available for this purpose. Hot notchers have a heating element that fuses the fibers adjacent to the notch in order to prevent fraying and the disappearance of the notch. It is a good choice with natural and knit fabrics, however, it cannot be used for thermoplastic fibers. It may also be available with adjustable heat control.
- Brands: Eastman’s Hot Notcher, ZXUY 1x pattern notched
- When markings have to be made inside garment parts, for example, marking the position of pockets, appliqués, darts, etc., drills are used. This machine consists of a motor that rotates the needle, a base plate, and a long needle. The needle penetrates completely at the specified point creating a hole or just shifting yarns.
- Certain drill machines are also equipped with a hollow needle that carries marking fluid that leaves a mark on the fabric plies. It is important that the marks remain till the particular sewing operation. Drills are problematic to use on loosely woven thick textured fabrics. Marking can also be done using thread markers which carry the thread through the entire spread and then individual threads are cut. It may also be done manually, on every ply using a template, but it is time-consuming.
- Brands: Eastman Drill machine
- Embroidery: processes that occur only if directly specified by the customer; therefore, these processes are commonly subcontracted to off-site facilities. Embroidery is performed using automated equipment, often with many machines concurrently embroidering the same pattern on multiple garments. Each production line may include between 10 and 20 embroidery stations. Customers may request embroidery to put logos or other embellishments on garments.
- Brands: SWF MAS-12 12-Needle Embroidery Machine, Brother Model PR 1000 Computerized Embroidery Machine
- Fusing and interlining are needed for the manufacturer to:
- Maintain consistent quality against hand operations.
- Save time and labor.
- Enable easy handling of small components.
- Reduce differential shrinkage between top cloth and interlining to controllable levels.
- Stitch, pucker and distort sewn products.
- Create garments with a cleaner and fresher appearance.
- Increase durability of garments.
- Modify slightly by interlining the handle of the cloth.
- Retain the garment’s original shape after repeated dry cleaning and washing.
- Reduce crease recovery time.
- Brands: Rudolf Sewing Systems – Industrial Fusing Machine, Electric Fusing Machine, Bharath Fussing – Automatic Fusing Machine
- Interlinings are additional pieces of fabric applied to particular garment sections, that may require further support.
- However, interlinings can also serve many other purposes, including to:
- Stabilize garment sections.
- Reinforce sections that may be weakened by subsequent operations.
- Maintain the shape of parts such as collars and lapels.
- Prevent seam impressions.
- Stiffen the garment or fabric.
- Strengthen the garment or fabric.
- Mask the transparency of fabric with sheer characteristics.
- Provide additional warmth, for example, quilting.