服裝基本制造流程.doc

INSPECTION DIVISIONTRAINING MATERIALTitle: Basic Manufacturing Process for Garment (Bag)Document No.:TRA-HKG-IT-003Revision No.: 3Issue Date: 01 March 2003Page: 49 of 49How To Make Up A GarmentGeneralities on sewing needs for Different GarmentsThe requirements for the manufacture of specific garments:The garments to be manufactured lead to designing the process of manufacture, which forms the basis of the sequence of operations in the sewing room, whose work content is measured by their standard times. Further the type of garment strongly influences the stitch type selected and the basic machinery used in the operations. The large component in the workplace layout influences the size of work-place required for the operations. The organization of inspection also stems partly from the type of garment.The feasible way to plan the production for the manufacture of specific garment is to produce a manufacturing specification sheet, from which we could state the general requirements to direct the method to making up the garment. For example, operation, machine type, seam type, stitch type, stitch density, and quality requirement (if possible). Method to prepare specification sheet:a. Analyse the structure of the specific garment.b. Break down the operation required to produce the requirement of each component, for example: the specific feature designed in the garment will require special methods, equipment, and attachment to be used to satisfy the requirement.c. Determine the suitability of the present equipment and machinery, which will influence the method to be used to make up the garment.d. Compile the customers requirement, quality requirement and tolerance.A.General manufacturing workflow for garments:Design Pattern markingSample makingSpreading Marker making Pattern Grading CuttingFusing Bundling Sewing Finished Garment FinishingB.General manufacturing processes for garments:1)DesignThe first step in producing a garment is the creation of the design and the construction of patterns for the components in the design. A good apparel design has three parameters:- emotional appeal (style), utility, and durability. The apparel manufacturer measures style objectively with a relative scale the profitable scale of the product.2) Pattern makingThe designer creates specific products in accordance with the trends. The Pattern maker drafts the pattern necessary to produce the creation. Apparel pattern are made with one of two basic methods:-a. Draping the garment on a form or model with muslin or the fabrics used to make the garment. The production pattern is traced from the muslin or fabric cuts. (Tailor Made)b. Drafting the pattern on paper with either direct measurements for the pattern or developing the pattern draft with the aid of a sloper (basic block).3) Sample makingIn the garment industry, it is traditional to indicate the requirement by means of a sample garment. The sample may be mock up (quickly make) of the designers or purchasers basic idea or requirement or it may show the requirement in detail.The sample is necessary to illustrate those aspects of design and manufacture which it is not possible (of practical) to describe in detail in words e.g. shapes of collars, pockets, flaps, etc. In general, it is possible to illustrate many of the features by means of drawings or photographs, but people engaged in garment production would usually find engineering type drawings difficult to understand without special training. Hence, the use of samples can ensure the manufacturer to understand the types of garment requested by customer and the correct production methods used for the further bulk production.a)Types of samples:Basically, there are Four types of samples:1. Initially sample2. Approval sample3. Salesman sample/Size set sample4. Shipment sampleI) Initially samplesPreparation:a) Material: should be the same material as requested by customers or as close as possible if unavailable.b) Colour: try to match the requirement if possible.c) Accessories: Use the exact requested accessories or as close as possible.Inspection:a) Dimension: measurement should be kept as the production sheet if indicated.b) Silhouette: according to the design illustration.c) Design detail: should follow the sketch exactly.d) Fitting: take care of the effect of cutting whether it is in proportion to the human figure and the drafting effect etc.II) Approval samplesPreparation:a) Material: should use the same material as requested by customers.b) Colour: match the requirement.c) Accessories: use the exact requested accessories.Inspection: a) Dimension: measurement should be kept as the production sheet as well as the measurement chart.b) Silhouette: must be kept according to the design illustration.c) Design detail: should follow exactly the production design sheet.d) Fitting: take care of the effect of cutting whether it is in proportion to the human figure and the drafting effect etc.e) Sewing faults:- stitch formation;- stitch tension;- seam slippage;- seam puckering;- needle heat and so on.III) Salesman sample (size set)Preparation: a) Material: must use the same material without any alternation.b) Colour: Any colour selected from customers in the order sheet.c) Accessories: must use the exact requested accessories.Inspection:a) Dimension: measurement should be kept as the production sheet (size specification).b) Silhouette: must be kept according to the design illustration.c) Design detail: should follow exactly the production design sheet.d) Fitting: Take care of the effect of cutting whether the pattern could make accordingly and it is in proportion to the human figure and its drafting effect.e) Sewing faultsIV)Shipment sample (Production sample)Everything must be conformed to the customers requirements.4) Pattern gradingIt is the drafting process of enlarging or diminishing a style pattern into patterns for other sizes. The function of grading is to see that this is accomplished with proper fit for the other size without changing the style sense of the original model.5)Marker makingBefore the cutter can begin his cutting operation, he has to have some plan of operations. Marking the fabric itself, in its simplest form, was originally marking in round a pattern the shape to cut by means of crayon, chalk or other making implement. The first step in calculating the optimum marker design is determining the basic geometric design of the marker. This is done by inspecting the grain markings on the patterns. The second step is to list or note the length of the warp and filling dimension in each pattern. Since most patterns are not rectangular, this means that two or more measurements must be taken for each dimension. The third step differs slightly with respect to the basic design type. The patterns that widths are marked in parallel formation across to the width. In patterns with tapered widths, maximum interlock efficiency results by inverting the alternate patterns in a manner, which interlocks a narrow width with a wide width. The marker makes notes the upright and inverted correlations required equalling the full width of the fabric. The application of pattern engineering is the shifting of seams to make the best use of cloth width. In one case, three trouser backs could be laid in 43” and four trouser fronts in 47”. The cloth width available was 45” and by shifting the side seam adding1/2” to the backs and taking 1/2” from the fronts, it was possible to lay three backs and four front in exactly 45”.6)SpreadingThe cloth is brought to the cutting table to be laid, ply on ply, or in single plies. The cloth may be spread on the table manually, or by machine. The procedure of cloth spreading is the placing of the material on the cutting table, laying one piece upon another, to a predetermined length. In giving consideration to the use of machinery, volume is usually the deciding factor, although quality and handling may be factors as well. Spreading is made easier by the use of spreading machines. Good spreading should result in a lay, in which each ply lies perfectly flat, without tension.7)CuttingAfter spreading, the marking-in must be carried out, so that the cutter will know what shapes and in what manner he is to cut up the lay. Marking-in may be done by marking directly on to the cloth, using perforated markers or by using paper markers. After marking-in the cutting operation is carried out. This may be by means of a portable cutting machine to do the entire operation, or dissecting the lay into sections with a cutting machine, and then cutting it on a band-knife. For some applications it is possible to cut the entire lay by using a die-press machine. After the various parts have been cut, the cut parts are passed into the sewing room. Various pieces of equipment are used during the procedure of spreading, marking and cutting.8)FusingIt is a method of joining fabric parts using techniques similar to pressing. Just as pressing uses heat, pressure and moisture to obtain its effect, so fusing uses heat, pressure and sometimes moisture, but during a measured time span, to obtain to its effect. The aim of fusing is to bond interlining to outer fabric in such areas as collar, cuffs, facings, lapels, edges, pockets and foreparts. The active agent in fusing is the resin, which coats the interlining. When interlining and outer cloth are pressed together under heat the adhesive resin melts and flows into the outer cloth. When the pressure is released, the fused parts cool, the resin solidifies and the bonding is complete. The factors to consider are the type of coating the type of resin, methods of testing the bond, the process itself, and equipment for fusing.9) BundlingA number of garments tied up together for carrying in some production system of clothing industries. The manner of folding or superposing the plies in the bundles should be such that there is (a) minimum or no creasing, and (b) minimum or no disarraying of the cut alignment. Any deviation from these two principles increases the pick-up and positioning time for the sewing operator. (Bundling can be done before or after fusing).10) Necessary procedures for some special design of garmentsa) Pleating skirt, we need to overlook and hemming and then send out for pleating.b) Embroidery, smocking, quilting, pin tuck etc.c) Re-cut or Re-bundle after the (a) or (b) process.11)SewingThe principles of garment construction concern:- The assembly of fabric parts to make a garment,- The addition of working parts to enable the wearer to put on and take off the garment- The decoration of the garment by stitching on the surface of the fabric and - The insertion of pockets whether decorative or functional sewing quality standard do strongly influence besides the style and design of the specific garment and the type of fabric and blends of the fibre content. They will affect the choice of:-Seam type-Attachment/Guides requirement-Stitch type-Workplace design-Stitch density-Handling method-Sewing thread-How to breakdown the operation-Sewing machined used (related to a & b)12)FinishingThis including hemming, washing, buttonholes sewing, button sewing, trimming, hand-stitch, final pressing and final inspection. The need to press garments during and after manufacture is a basic requirement to form and shape a specific design. The effect is to give an eye-catching appeal to the wearer, to present a clean and smart appearance, together with a distinctive and flattering silhouette. Under-press and off-press of a specific will be different according to the physical requirement and the quality standard:-(a) Type of pressing equipment used(i) Hand iron(ii) Steam iron with or without heating element(iii) Steam press (Hoffman type) with special Buckse.g. sleeves, collar, shoulder, open seam.(iv) Steam body former(v) Shirt ironing system and folding system(vi) Ironing table(b) Temperature, pressure & vacuum adjustment(c) Pressing methodFinal inspection tolerance and the standard of quality control will affect the inspection method used to measure the acceptance of the order, this is strongly subject to the management policy:(a) Workmanship(b) Dimension(c) Packing detailsPacking may have two major functions: distribution and merchandising. The basic types of package forms used in apparel and allied products are bags, boxes, cartons & cases.C.Special problems related to the specific garment1) Different types of garment would have different production problems. They might be caused either one or more of the following factors:A.Design of the garment Pattern cutting, material used, and the make up of Garment.B. Customers requirements special effects added to the specific garment, Adjustment and particulars.C. Quality requirements Seam type, stitch type, tolerance etc.The special problems to make up the specific garment in the production processes may be classified as:i) Cutting problemsii) Fusing problemsiii) Sewing problemsiv) Pressing problemsBesides the manufacture process, there may be a special problem in packing specific garment.2) Special problems in making up a specific garment are caused by:a. Nature of material used fabric, sewing thread, interlining, lining and Accessories used etc.b. Machinery and Equipment use cutting tools, spreading method related to the machine used, fusing machine, ironing and pressing equipment have a close relationship to tackle the special problems of specific garment.c. Making up method used the handling method used at the workplace, special skill required, and the skilfulness of individual operative.d. Effectiveness of Quality Control and Inspection.Special problems of specific garment sometimes could be found as we analysed the operation and structure of the garment. But it is not easy to predict the problem to be happened even though we prepare the approval sample. It would be created in actual production as the above captioned causes.Stitch, Seam and StitchingStitch Formation:Definition of StitchA stitch is one unit of conformation of thread resulting from repeatedly passing a strand or strands and /or a loop or loops of thread into or through a material at uniformly spaced intervals to form a series of stitches.British Standard classification of Stitch typesSince the invention of the sewing machine, improvements, advances and changes in machines and in the art of sewing have resulted in many new stitches and machine types. These different types are referred to by names or terms which very widely throughout the industry. To avoid the confusion caused by this multiplicity of names it is proposed, hereafter, to refer to stitches according to the British Standard scheme, set out in BS 3870: 1965 which classifies stitches as shown below.For the sake of precision in describing these stitches the following three terms are defined in the British Standard.Interlooping:The passing of a loop of thread through another loop formed by a different thread.Intralooping:The passing of a loop of thread through another loop formed by a same thread.Interlacing :The passing of a thread over or around another thread or loop of another thread.Classification Stitches are divided into eight classes, within each of which are several types of stitch. The characteristics of each class are indicated below together with some typical applications.Stitch Class:100SINGLE THREAD CHAINSTITCH200 HANDSTITCH300LOCKSTITCH400 TWO-THREAD CHAINSTITCH (MULTI-THREAD CHAINSTITCH)500 OVEREDGE STITCH (OVERLOCK STITCH)600 COVERING STITCH (FLAT SEAM STITCH)700 SINGLE-THREAD LOCKSTITCH800COMBINATION STITCHStitch Class 100 ChainstitchThese are formed by one or more threads introduced from one side of the material only. Single thread chainstitches are often used for temporary stitching (e.g. basting) or for blind stitching. Particular care is required to prevent runback from the last stitch. Stitch Class 200 Hand StitchThis class of stitch is formed by hand with one or more needle-threads and has for a general characteristic that each needle-thread passes through the material as a single line of thread and the stitch is secured by the single line of thread passing in and out of the material or intralooping of the threads with themselves. When more than one thread is used, the threads pass through the same perforations in the material (e.g. type 201 Saddle stitch). Origination as hand stitches they are now often formed by machines.Stitch Class 300 LockstitchLock stitches are formed by a needle thread or threads, introduced from one side of the material, interlacing with an underthread supplied from a bobbin on the other side. The simplest, type 301, has similar appearance on both sides with low bulk when correctly balanced and tight strong seams can be produced with good strength and abrasion resistance. Its disadvantage is the limited length of sewing possible before having to replace the bobbin. In applications requiring stretch, types 304, 321 or 322 can be used wherein successive stitches form a 1, 2, or 3 step zig-zag pattern.Stitch Class 400 Two-thread Chainstitch (Multi-thread Chainstitch)These differ from Class 100 stitch types in that a separate under or looper thread is used and this generally lies on the underside of the material, the needle thread(s) being drawn through to balan