Defect Accounting
Quantitative tracking metrics record the volume of damaged or incorrectly printed paperboard generated during actual press runs following make-ready completion. Printing press spoilage accounts for substrate sheets or web length rejected due to color drift, register mis-alignment, ink smudging, or mechanical damage during active production. This metric defines net print loss, stopping short of initial machine setup waste created before production sign-off.
Waste Categorization
Unlike planned setup waste, spoilage represents unpredicted operational failure that directly reduces job profitability and wastes valuable raw paperboard stock. Common causes include fountain solution imbalance, automatic feeder double-sheet jams, plate wear, and linting caused by weak paper surface strength. Automatic inline vision systems scan passing webs at full line speed to detect graphic defects, automatically flagging bad sheets for mechanical ejection at the press delivery pile.
Estimators factor baseline spoilage allowances into production orders, typically allocating one to two percent of total job volume depending on substrate complexity. High spoilage rates indicate mechanical press wear, sub-standard paperboard surface properties, or improper pressroom environmental control.
Process Mitigation
Analyzing spoilage records pinpoints recurring substrate defects such as surface picking or dusting from paperboard edges. Reducing run-time printing waste preserves raw material stock and improves press output capacity. Corrective press maintenance directly lowers job spoilage percentages.
