In short
- Measure ink use per sheet from the RIP’s estimate (colour ml + white ml)
- Add film per sheet and powder per sheet
- Divide by usable transfers, then add 15–25 % for waste and reprints
The four numbers
- Colour ink: DTF CMYK costs about $0.15–0.25 per ml on a converted Epson. A full A4 sheet at typical coverage uses 0.6–1.2 ml.
- White ink: $0.20–0.35 per ml, and a full-coverage A4 uses 1.5–3 ml — white is usually the largest ink line.
- Film: $0.30–0.60 per A4 sheet, or $12–25 per 30 cm × 100 m roll ($0.06–0.10 per A4 equivalent).
- Powder: $0.05–0.15 per A4 at normal coverage.
Worked example (A4, 70 % coverage)
Colour 0.9 ml × $0.20 = $0.18. White 2.2 ml × $0.28 = $0.62. Film sheet $0.40. Powder $0.10. Total $1.30 per sheet. With six 8 cm logos nested on the sheet, that is $0.22 per logo before waste.
The number nobody counts
Waste. Nozzle checks, purge strips, a misfed sheet, the reprint for the customer who sent a JPG. Real shops see 15–25 % of film and ink that never becomes a sold transfer. Add it to the cost, not to the profit.
Time
An A4 at 1440 × 720 takes 3–5 minutes to print plus curing. If your hour is worth $25, that is $1.50–2 per sheet — more than the ink. Nesting more designs per sheet (gang sheets) is the only way to get that number down.
