ForgeWhen someone asks for my hourly rate, I answer with a question: an hour of what? An hour of a machine printing on its own overnight and an hour of me sanding off supports have nothing in common. Mixing them up is the mistake behind absurd quotes, too low or too high. Here is how I build a machine hour, item by item, with measured power draw and a complete example.
Two hourly rates, not one
There is the machine hour: the price of one hour during which the printer is tied up by your job. It runs whether you are there or not. And there is the labour hour: the price of one hour of your own work, when your hands are on the part or on the file. In my workshop the first is €2.15 (€2/h for printing plus €0.15/h for wear), the second €20/h for post-processing and €23/h for modelling. Nearly a factor of ten between them, and that is normal: the machine is not doing the same work as you.
What a machine hour has to cover
1. Electricity, measured, not guessed. Manufacturers publish their measurements. Bambu Lab gives an average printing power of 105 W for both the P1S and the X1C in PLA, and 140 W (P1S) to 150 W (X1C) in ABS. Prusa states 80 W in PLA and 120 W in ABS for a printer from its MK series. These are averages over short test prints, bed heating included; a plug-in power meter left on during a real print of several hours will give you your own figure.
The price per kWh depends on your country and your contract, so take it from your bill. Two examples for November 2026: in the UK, Ofgem's price cap sets an average electricity unit rate of 26.32p per kWh for direct debit customers from 1 October to 31 December 2026; in France, EDF's regulated Base tariff has been €0.2001 per kWh including tax since 1 August 2026. At the French rate, an hour at 105 W costs €0.02 and an hour at 150 W €0.03; at the UK cap, roughly 3p and 4p. That matches my 0.3 kWh for two hours of PETG. Electricity is real, but it is barely more than 1% of my machine hour.
2. Depreciation. The machine's price divided by the hours it will run in its life. A €600 printer over about 4,000 hours is €0.15/h; a 1,200-euro machine over 6,000 hours, €0.20/h. That is the wear line on my quotes, and it is the money for the next machine.
3. Wear parts. Nozzles, build plate, belts, PTFE tube, fans: €50 to €100 a year on a machine that works, so 3 to 10 cents an hour. I don't give them a separate line: they are included in the €2/h for printing.
4. Occupancy. This is the bulk of the rate, and the most misunderstood part. For six hours your machine is taken: you cannot start the next job on it, it takes up your space, and if it fails near the end, you are the one who starts again. The €2/h for printing does not pay for power: it pays for that tied-up time.
5. Supervision. Starting the print, checking the first layer, staying reachable, coming back to remove the part and clean the plate: a few minutes per print, not hours. In my rates those minutes are inside the machine hour. What is not inside it is real work on the part.
Why two lines: printing and wear
I keep the €2/h for printing and the €0.15/h for wear apart because they move for different reasons. Wear depends on the machine: a more expensive printer or a resin machine does not depreciate the same way. Printing depends on your workshop and your workload: if your machines sit idle half the time, this is the figure that has to cover the empty hours. Keeping them apart means you can change one without touching the other, and explain every line to the customer.
The complete example: a 6-hour print
A PETG enclosure, file supplied by the customer: 110 g and 6 h of printing according to the slicer, then a quarter of an hour to remove supports and deburr.
| Item | Calculation | Amount |
|---|---|---|
| File analysis | file supplied | €2.00 |
| Material (PETG) | 110 g × €0.04/g | €4.40 |
| Machine wear | 6 h × €0.15/h | €0.90 |
| Printing | 6 h × €2.00/h | €12.00 |
| Post-processing | 0.25 h × €20/h | €5.00 |
| Total | €24.30 |
The machine hour accounts for €12.90 of the €24.30, more than half. All in, the job comes to €4.05 per hour of printing. And the electricity is inside it: six hours at about 150 W is 0.9 kWh, €0.18 at the French regulated rate or about 24p at the UK cap.
The mistakes I see most often
Counting only electricity. On the example, that gives €0.18 for six hours of machine time instead of €12.90. The customer is delighted, and you pay for the machine, the nozzles and the supervision out of your own pocket.
Charging your labour while the machine runs on its own. Six hours at €20/h is €120 for an enclosure nobody will buy at that price. Your labour rate only applies to the time you actually work: post-processing, modelling, checking the file.
Taking the power supply rating for consumption. Bambu Lab lists 1,100 W at 220 V for the P1S: that is what the supply can deliver, not what the machine draws on average (105 to 140 W). With the wrong figure, your electricity comes out ten times too expensive.
Inflating wear. For a long time I counted €0.50/h without being able to justify it: the calculation gives €0.15 for a €600 machine.
One rate for every machine. A 1,200-euro printer or a resin machine has neither the power draw nor the depreciation of an entry-level printer. One rate per machine, not one rate per workshop.
How to set yours
Measure each machine's consumption on a real print, take the price per kWh from your bill, divide the machine's price by an honest lifetime, and decide what an hour when it is unavailable is worth to you. These rates are mine; yours depend on your machine, your region and your customers. Building the full price is covered in the guide How much should you charge for a 3D print?, and the cost price, with no margin, in The real cost of a 3D print.
Read also: How much should you charge for a 3D print? · The real cost of a 3D print · the online calculator
ForgeCalc sets no prices: it calculates with yours. ForgeCalc reads the print time from your sliced file and applies your machine hour, your wear rate and your labour rate; for a first figure, the free calculator does the same calculation online.