Print farm throughput and cost per part

Researched from published specifications and material data · Standard formula, convention inputs

Quick answer

Four printers running 20 hours a day at 4 parts per 6 hour plate with a 90 percent success rate produce about 48 good parts a day. Cost per part is material plus electricity plus labour plus depreciation, divided by the success rate.

The throughput arithmetic is exact. Depreciation life and labour per part are business assumptions you should set from your own numbers.

Print farm throughput and cost per part Standard formula, convention inputs
Cost per good part $2.32
Good parts per day48.0
Good parts per month1440
Material, after failures$1.33
Electricity$0.034
Labour$0.93
Depreciation$0.03
Machine hours per part1.50 h

Every cost is divided by the success rate, because a failed part consumes material, electricity and machine time and sells for nothing.

Labour is usually the surprise. At eight minutes a plate and four parts a plate, handling costs more per part than the filament does.

Formula: good_parts_per_day = printers x (hours / plate_hours) x parts_per_plate x success_rate

Machines and material for a farm

Common questions

What success rate should I assume for a print farm?

A well tuned farm running a known part in a known material holds 90 to 97 percent. A farm running varied one off jobs in mixed materials is doing well at 80 percent. The number is worth measuring rather than assuming, because it multiplies every other cost on the page: at 50 percent success, your material cost per sold part doubles.

Is electricity a significant cost?

Rarely. A typical benchtop machine averaging 120 W over a six hour plate uses about 0.7 kWh, which is a few cents per part at normal rates. It becomes visible only at large scale or with heated chambers and many machines, and even then it is usually smaller than the labour of picking parts off plates.

How many printers can one person run?

The limit is handling time, not machine count. If each plate needs eight minutes of attention and plates finish every six hours, one person can service roughly 45 machines in an eight hour shift on paper, and far fewer in practice once failures, maintenance and packing are included. Most small operations find one person comfortably manages 10 to 20.

Should I count the printer purchase in the cost per part?

Yes, if you want the number to mean anything. Spreading the machine cost over its useful life is what tells you whether a job is profitable, and at typical volumes it adds a surprisingly small amount per part. A $400 printer over three years at 12 good parts a day is under four cents a part.

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