Cutting | Fabric Cutting

Cutting is the major operation of the cutting room, when the spread fabric is cut into garment components. Of all the operations in the cutting room this is the most decisive, because once the fabric has been cut, very little can be done to rectify serious mistakes. Cutting can be done manually using powered knives or by computer-controlled system.

Requirements of the Cutting Process-

1. Precision of cut- It depends on :
         - Methods of cutting employed.
         - Marker planning- distance between two pattern pieces.
         - Marker marking- correct marking by pen/pencil.
         - Condition of cutting equipment- machine, blade etc.
         - Skill and motivation of the operator. 
2. Clean edge- Free from fraying.
3. Unfused edge- High temperature produced during cutting can fuse fabric edges by melting. Unfused edges can be ensured by taking the following measures: 
         - Well sharpened blade.
         - Use of anti-fusion (heat absorbent) paper.
         - Spraying silicon lubricants on the blade.
         - Less cutting speed.
         - Reducing the height of the lay. 
4. Support of the lay- using a polyethylene sheet or nylon bristle under the bottom ply
5. Consistent cutting- all plies should be of same dimension

Cutting Techniques-

Manually Powered Knife: Rotary blade- small instrument, electrically operated octagonal blade, very sharp edge, grinding wheel attached, fabric should be clamped before cutting. Suitable for relatively gentle curve cutting & for less ply height.

Straight blade- straight reciprocating blade of upto 13" height and 0.5" width could be sharpened by attached grinding wheel. Most commonly used, could be used for larger depth of fabric, high cutting speed, sharp corners could be cut; but blade deflection occurs and higher the depth of fabric greater the possibility of deflection

Band knife- endless loop of flexible blade, one side sharpened, thinner than straight knife, machine stationary whereas the fabric moves, much more accurate cut for smaller parts, suitable for cutting sharp corners. Not suitable for large parts, more fabric wastage as block piece of fabric is required; workload is high due to stationary cutting machine.

Die cutter- suitable for smaller garment parts like shoulder pads, very accurate for sharp corners & circular patterns. Not suitable for larger parts, difficulty in producing dies (labour, time), higher fabric wastage due to use of block pieces

Computerized Technique:
     - Knife cutter
     - Laser cutter
     - Water jet 

Plasma jet Choice of Cutting Technique: The following points should be considered while choosing cutting techniques:

1. Availability of cutting machines.
2. Number of plies or spread height- band knife for up to 6" height, straight knife for higher height.
3. Type of garment parts- straight knife & knife cutter for bigger parts, band knife for sharp corner, die cutter for small parts like pockets.
4. Type of fiber in the fabric- laser cutter should not be used for thermoplastic fibers, water jet is suitable for low absorbency fibers like polyester.
5. Cutting speed required- computerized method for higher speed.
6. Quality of cutting- computerized techniques for high quality cutting.
7. Volume of production- straight knife & computerized techniques for higher volume
8. Cost of cutting.