3D print batch pricing: share setup costs without hiding work

Ten minutes of preparation costs $3 at an $18 hourly labor rate. For one item, that item carries all $3. Spread the same preparation across four items and each carries $0.75. Across eight, it is $0.375 per item. This is a shared cost, not a reason to divide every cost by eight.

Plate preparation repeats if you need another plate. Finishing each item repeats even if every item fits on the first plate. Keep those scopes separate so a larger batch does not erase real labor.

Consider a single-plate order with one, four or eight successful items. Each item uses 20 g of filament at $20/kg, three minutes of finishing at $18/hour and $0.50 packaging. Preparation takes ten minutes per order plus two minutes per plate.

For this example, slicer estimates are one hour, 1.75 hours and 2.75 hours respectively. Power averages 100 W at $0.20/kWh. Hypothetical selling fees are 3% of the product subtotal plus $0.30 per order, with a 30% target margin. Shipping, extra components, overhead, machine wear and failed prints are zero. These assumptions illustrate the arithmetic, not typical printer performance or marketplace rates.

Order cost is $3.60 of setup and plate labor, plus $1.80 per item, plus $0.02 per printer-hour. Target unit price is (order cost + $0.30) ÷ (0.67 × units), rounded upward to the nearest cent. Costs and fees use unrounded values; displayed money is rounded. Multiplying rounded unit costs may therefore differ from the displayed order total.

Eight units leave more order profit, but the printer also stays busy longer. Profit per printer-hour rises only from about $2.56 to $3.00 here. A lower unit price is only one part of the decision.

1. Set finished units to the number of items you will sell across this order.
2. Set Plate runs to repeat each layout. The estimate multiplies its filament, print time and handling by that count.
3. Enter filament per plate run, including supports, purge and waste. Eight 20 g items need 160 g before any additional waste.
4. Use the slicer’s total print time for the actual layout. Do not assume eight items take the same time as one.
5. Enter preparation once, plate labor per plate and finishing minutes per unit. Packaging has separate per-unit and per-order inputs.
6. Check whether each fixed fee applies per order or per unit, then review the cost breakdown.

Free supports one repeatable plate layout with multiple filaments. Maker adds multiple plates, separate filament detail, printer wear and failure assumptions. Locked paid costs remain excluded on Free. Maker and higher also let you keep temporary scenario baselines while testing a different batch; save a calculation if you need to retain its inputs.

These examples treat the whole batch as one order. Selling eight items to eight separate customers may repeat fixed fees, order packaging and shipping eight times. Recalculate those orders rather than borrowing the single-order result.

More items on one plate can change print time, purge waste, surface quality and the consequences of a failure. Use your actual layout and failure history when those matter. A retry reserve cannot guarantee that a particular plate will succeed.

Producing more unsold stock ties up cash and printer capacity. Compare likely demand, delivery deadlines and absolute profit alongside margin and printer-hour profit. The metric describes estimated occupied machine time; it is not an hourly wage, a utilization measurement or a sales forecast.

Start with the smallest batch that makes sense for the order. Compare a larger one using revised filament and time, then decide whether the saved preparation justifies the extra work.