- Material to buy
- monthly requirement ÷ (1 − wastage %)
- Filament material cost / month
- filament bought × filament price per kg
- Pellet material cost / month
- pellets bought × pellet price per kg
- Material saving / month
- filament material cost − pellet material cost
- Net monthly saving
- material saving − extra running cost for pellet printing
- Annual net saving
- net monthly saving × 12 (at your current usage rate)
- Material cost reduction
- material saving ÷ filament material cost × 100
- Break-even pellet price
- (filament material cost − extra running cost) ÷ pellets bought
- Cost per part
- material cost × 12 ÷ parts per year
- Additional investment
- pellet printer − filament printer (when buying instead of a filament printer)
- Payback period
- investment counted ÷ net monthly saving
Example: if the same material costs ₹1,000/kg as filament and ₹250/kg as pellets, the raw material cost difference is ₹75,000 for every 100 kg consumed.
Payback example: a material saving of ₹13,200 a month minus ₹1,500 extra running cost gives a net saving of ₹11,700. If the pellet printer costs ₹6,00,000 and the filament printer you would otherwise buy costs ₹5,00,000, the additional investment is ₹1,00,000 and pays back in about 8.5 months. Bought as an additional machine, the full ₹6,00,000 would take about 51.3 months.