Page 265 - Industrial Cutting of Textile Materials

252 Industrial Cutting of Textile Materials

Matching Cutting Take-off segment
segment segment

Fig. 15.18 Three stages of the ‘Topcuť pattern matching and cutting system by Bullmer.

15.3.5 Advantages and disadvantages of the semiautomated
work methods

Semiautomated way of cutting of multi-ply spreads with matched pattern can be per-
formed in one cutting step only, not using fabric allowances around pattern pieces in
markers. Thus, time and work consumption is reduced significantly. The use of an
overhead projector eases manual pattern matching in multi-ply spreads. The use of ini-
tial markers saves time and speeds up nesting process. Cutting can be performed by an
automated cutter increasing significantly cutting quality and productivity. However,
pattern matching in multi-ply spreads is still performed in manual way. It signifi-
cantly complicates work process and reduces its productivity. Existing multi-ply fab-
ric spreading methods cannot ensure balanced/perfect fabric ply structure and pattern
to perform an efficient pattern matching and avoid fabric loss obtained compensating
pattern-matching impressions.

15.4 Future trends

Every fabric ply has its own structural distortions different from other fabric plies.
Manual multi-ply processing of intricate pattern fabrics reduces this problem fixing
the main points of the fabric pattern on pins and mutually coordinating these points in
between all fabric plies in a spread. However, the perfect pattern matching is achieved
only in these points. In between them, pattern still can be more or less distorted/unco-
ordinated. The fewer pins are used and are placed more far from each other, the larger
possibility to get cut components with imperfect pattern placement. Thus, the number
of pins to fix/coordinate pattern has to be large. The more complicated the pattern is
and the more flexible fabric structure is, the more pins should be involved in a work
process. However, a large number of pattern points to match manually would increase
time and work consumption in inadmissibly great extent.
Obviously, new tools to perform fabric structure and pattern balancing/perfection
have to be found and developed. The fabric ply should be spread on a large number of
pins. Based on the fabric ply image, movement coordinates should be determined for
every pin to move it. Realizing the movement of all fixed pins, the fabric ply structure/
pattern should become perfectly coordinated. Besides, to perform multi-ply spreading,
certain mechanical manipulations with the fabric ply (to correct its structure/pattern)
have to be done before it is laid on a previously spread ply. Only then, the entire
spread will have ‘perfectly coordinated pattern’, ready for a marker without any fabric
allowances around pattern pieces (reaching the highest fabric utilization level) and
high-accuracy cutting by an automated cutter.