preproduction operations: marker making, spreading, and cutting
Post on 13-Jan-2016
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Preproduction Operations:marker making, spreading, and cutting
1. Marker Making
• Preproduction operations are depend on perfected patterns
• Pattern makers develop the patterns for styles
• All the patterns of a style are verified
Cut Order Planning
• Cut order planning translates customer orders into cutting orders
• It is the process that coordinates customer orders with all the variables of marker making, spreading, and cutting to minimize total production costs and meet customer demand for timely products
• It seeks the most effective use of labor, equipment, fabric and space
• The result of cut order planning are cutting orders
Common Variables: may affect cut order planning
• Number of colours in order• Maximum spread length, depend about
cutting table• Maximum ply height, depend about material
and cutting equipment• Fabric cost per meter/yard• Useable cloth width• Etc.
A Marker• A marker is a diagram of a precise arrangement of
pattern pieces for a specific style to be cut from single spread
• Marker making is the process of determining the most efficient layout of pattern pieces for a specified style, fabric, and distribution of sizes– Manually produced markers– Computerized marker making
• Plotting is the process of drawing or printing pattern pieces or markers on paper so they can be reviewed or cut.
Marker with detail names
Dimensions of Marker
• Markers are made to fit the cut table widths of fabrics
• Cut table width is the usable portion of the fabric width. Selvages are often not usable
• If a marker is narrower than usable width, the unused fabric is wasted
• If a marker is wider than the specified fabric, chair parts located on the edge of the marker will not be complete
Sectioned Markers• Sectioned markers contain all of the pattern
pieces for one style in one or two sizes• Sections may be used separately or joined
together to form multi size marker
Splice marks
• Splice marks are points in a marker where fabrics can be cut and the next piece overlapped to maintain a continuous spread
Marker Efficiency• Marker efficiency is determined by fabric utilization, the
percentage of the total fabric that is actually used in upholstery textile parts
• The area not used in product parts is waste• Marker efficiency depends on how tightly the patterns
pieces fit together within the marker• Factors that affect marker efficiency are:– Fabric characteristics– Shapes of pattern pieces– Grain requirements
Fabric Characteristics
• Fabric characteristics that affect utilization include:– Differences in face and back– Lengthwise directionality– Crosswise symmetry– Need for matching the fabric design– Length of design repeat– Fabric width
Characteristics of Pattern Pieces
Patterns are sometimes modified to increase fabric utilization. The following pattern adjustments may be used to improve fabric utilization:– Splitting pattern pieces and creating a seam– Rounding or slanting corners– Reducing seam allowances– Adjusting grain lines– Modifying the grain lines– Adjusting pattern dimensions
Types of Markers• Markers made with full-pattern pieces are called
open markers• Markers made with half pattern pieces for laying along
the folds of the tube are called closed markers
Marker maker must consider the symmetry (side to side) and directionality (end to end) differences on fabric:– Symmetric fabrics are the same side to side– Asymmetric fabrics are different side to side– Non-directional fabrics are the same end to end– Directional fabrics are different end to end
Modes of Marker
1. Nap-either-way: symmetric, non directional fabrics, considering only grain line
2. Nap-one-way: asymmetrical and directional fabrics, all pattern pieces be placed on a marker in only one direction
3. Nap-up-and-down: some directional fabrics all the pattern pieces of one size to be placed in one direction and another size placed in the opposite direction
2. Spreading
• Spreading is the process of superimposing lengths of fabric on a spreading table, cutting table, or specially designed surface in preparation for the cutting process
• A spread or lay-up is the total amount of fabric prepared for a single marker
• A spread may consist of a single ply or multiple plies• The height of a lay-up is limited by fabric
characteristics, size of the order to be cut, cutting method, and the vertical capasity of the spreader
• The number of plies in a spread may range from 1-300
Spreading Modes• A spreading mode is the manner in which fabric plies are
laid out for cutting• Two fabric characteristics that determine the spreading
mode are:– The direction of fabric face– The direction of fabric nap
Spreading Quality
A high quality spread has the following characteristics:– Is free of noticeable defects in the fabric– Is tension free– Is flat– Selvages are accurately aligned at least on one edge– Is free of static electricity– Is accurately spliced with minimal waste– Is the precise length, mode, and number of plies
specified
Spreading Equipment
Basic spreading equipment consists of:– spreading surfaces– spreading machines– fabric controll devices– fabric cutting devices
• Spreading requires a flat, smooth surface • Spreading and cutting surfaces are available in
standard width that correspond to fabric width
Spreading machine and table
Spreading Machines
• https://www.youtube.com/watch?v=UjoV8iB2IWs
Parts of Automatic Spreading Machine• Cutter device: Dismountable fabric spreading auto-cutter is available here
and travel length and speed of cutter can be easily adjustable.• Automatic Lifting device: This device automatically lifts the layer of fabric
at the time of spreading and the lifting gauze is changeable.• Edge control sensor : This device controls the edge of fabric.• Emergency stop: It has break line under the two side of table these break
lines are can be pulled at the time of emergency to stop the machine immediately.
• Bucket for roll fabric: This device automatically relaxes the fabric in tension and release the tension of fabric.
• Fabric loading sensor: This device returns the spreader machine back to original position when fabric runs empty.
• Expander roller: It catches the fabric both one way and face to face during spreading.
• Operation panel : This display enables the user to set up the length of fabric and control the number of layer of fabric easily
Advantage Spreading Machine• Auto ply cutting device for spreading of fabric • Auto ply counting arrangements • Auto catcher to gold the ends of the ply• Auto fabric tensioning device is used for spreading of fabric• Fabric selvedge alignment is done by photo electric guide• Fabric fault detector is used in spreading of fabric • Macine gives automatically a signal when spreading of fabric
is done• All kind of fabric can be spreaded and all kind of fabric lay can
be prepared in this machine• Fabric spreading can be done very quickly. Less labor cost by
spreading of fabric
3. Cutting
Cutting is the preproduction process of separating a spread into upholstery cover parts that are the precise size and shape of the pattern pieces on a marker
Cutting Quality• Cutting quality can be judged by:– The accuracy– Condition of cut edges– Precision of cut upholstery cover parts
• Factors that cause cutting inaccuracies are:– Wide or vague lines on the marker– Imprecise following of lines on the marker– Variation in the cutting pitch– Shifting of the spread or block– Fabric bunching up or pushing ahead of the knife– Improper equipment– Improper cutting sequense as parts are cut
Cutting equipment
Portable cutting knives- can be moved to and through a spread by an oprator:
1. Rotary or round knives- is used primarily for stright cuts and large radius curves
2. Stright knive- make only lateral cuts into a spread
Automated cutting systems:3. Blade cutting4. Laser cutting5. Water jet cutting6. Plasma jet cutting
Gerber Paragon Continuous Cutting
• https://www.youtube.com/watch?v=JMLyodv1nT0
Home Task1. Find the cutting equipment for your project:– Pattern and marker making software– Spreading machine and table– Cutting machine and table
2. Present the technical specifications for all equipment
3. Form correctly as a part of final report
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