The question we hear most from people new to 3D printing is: how much does this model cost me? The quick answer most people give — check the spool price and divide — is incomplete. Filament is part of the cost, but it is not the whole cost. If you print for yourself and get the numbers wrong, the pile of empty spools at the end of the month will surprise you. And if you print for customers and price on filament alone, you will be working at a loss while thinking you are making a profit.
In this guide we break down the real cost of every part that comes off the printer: filament, waste, electricity, consumables, failures, machine depreciation and your own time. Each item comes with a formula you can start using today.
First: filament cost and the basic formula
Every slicer (Cura, OrcaSlicer, PrusaSlicer and Bambu Studio) gives you two important numbers after slicing: the weight of the part in grams and the print time in hours. From the weight you get the material cost directly:
Filament cost = (part weight in grams ÷ 1000) × price of a one-kilogram spool
So a part weighing 40 grams uses 4% of a one-kilogram spool. This number — not a guess by eye — is the correct starting point. And because most everyday work (prototypes, brackets, boxes) is printed in PLA, the smart move is to keep an economical PLA spool aside for tests and for tuning your settings, before you burn expensive filament on a print you are still experimenting with.
Second: the waste that does not appear in the slice
The part weight the software shows is not everything that will actually be spent. Add to it the prime line at the start of the print, the brim, the supports, and the purge left over when you change a spool. The rule professionals follow is to add about 10% on top of the part weight as realistic waste:
Actual material cost = (grams ÷ 1000) × price per kilogram × 1.10
And waste jumps a lot in multi-colour printing, because every colour change forces a nozzle purge and a lump of filament thrown away. If you work with a multi-filament feeding system such as the CFS, count the purge block honestly inside your cost — on some colourful models the purge block comes out heavier than the part itself. The answer is not to give up colour, but to reduce the number of colour changes per layer at the design stage.
Third: electricity is cheaper than you think, but it is not zero
An open printer (no enclosure) usually draws around 120 watts while running, while enclosed printers or ones with a heated chamber draw between 200 and 400 watts. The formula is simple:
Electricity cost = (watts ÷ 1000) × print hours × price per kilowatt-hour
The largest share of that consumption goes to the heated bed, not to the nozzle, which is why printing ABS (bed at 90–110 °C) costs more in electricity than PLA (bed at 50–60 °C) for exactly the same part. And in Iraq, where the unit price differs between the national grid and the neighbourhood generator, work out your own kilowatt price — a ten-hour print overnight on the generator changes the whole equation.
Fourth: failure is the most expensive item and the one most often forgotten
A print that fails at the eighth hour out of ten means losing filament, electricity and time all at once, and it means starting everything from zero. Most failures come down to one thing: the part came loose from the bed, or its corners warped. Here the print surface matters more than any setting in the software. Double-sided PEI plates hold the part while it is hot and release it the moment the plate cools, with no glue, no tape and no digging with a knife — and the second side lets you start a new print immediately while you remove the previous part.
The same principle applies to smaller machines, on the condition that the plate matches the size of the machine itself; a plate that does not fit, or one that is warped, is a direct cause of a ruined first layer — and the first layer is what decides the fate of the whole print.
Fifth: consumables — the nozzle really does wear out
This item is always forgotten in the maths. Filaments with abrasive fillers, such as carbon and wood, eat the brass nozzle. Manufacturer tests showed clear wear on a brass nozzle after only about 250 grams of carbon-filled filament, while a hardened steel nozzle went past 2.5 kilograms with no wear worth mentioning. So if you print carbon with a brass nozzle, add the cost of a new nozzle roughly every quarter kilo — and that alone can turn your numbers upside down.
Carbon-reinforced PLA gives higher stiffness, better dimensional stability and an elegant matte look, and it is excellent for engineering parts and brackets. Its condition: a hardened steel nozzle, preferably 0.6 mm, with a nozzle temperature near 220 °C and a bed at 60 °C.
The same story goes for wood filaments, which give a beautiful natural texture, smell and colour: the recommended setup is a 0.5 to 0.6 mm nozzle, a nozzle temperature between 190 and 215 °C, and a speed slower than ordinary PLA, around 50 to 60 mm per second, to avoid clogs. Try them with a 0.4 brass nozzle and you will spend your time clearing blockages instead of printing, and every clog means a wasted part.
Sixth: ABS and an extra cost called the environment
ABS is excellent for parts exposed to heat or sun, and that is a serious consideration in an Iraqi summer, where PLA softens inside a car. But its real cost is higher than the spool price: it needs a nozzle at 230 to 250 °C, a bed at 90 to 110 °C, and an enclosure that keeps the air warm around the part. If the ambient temperature drops below roughly 45 °C, you will get layer separation and cracking — that is, a failed part and wasted filament after long hours. Count the cost of enclosing and venting inside the project before you start, not after the first failure.
Seventh: machine depreciation and the value of your time
If you print to sell, the printer itself is a cost item you cannot ignore. The simple method: take the price of the machine and divide it by the number of running hours you expect over its useful life, and you get a depreciation cost per hour that you add to every print. Add your own time on top: design, slicing, support removal, sanding and finishing. Time is the difference between a hobby you spend on and work that feeds you, and a machine with a large print volume, a screen and remote control reduces the number of interruptions and raises the success rate — and that in itself is a saving.
Bambu Lab A1 — automatic calibration that lowers the cost of failure
If the heaviest item in your maths is failed prints, then a machine that calibrates itself saves you more than it looks. The Bambu Lab A1 is an FDM printer with a bed-slinger design (a moving bed) and full automatic calibration, meaning you do not have to set the nozzle height by hand before every print or fiddle with screws. The result is a successful first layer time after time, less filament thrown away, and less time spent standing over the machine — and both of those are cost items, as we explained above. Its ease of use also makes it a logical choice for a beginner who wants to start calculating a real cost from the first week instead of losing a month to trial and error.
Bambu Lab A1 Combo — multi-colour, with the purge block in your maths
The Combo version is exactly the same A1 printer, and the one essential difference is that it comes with the AMS Lite system, which changes filaments automatically and so opens the door to multi-colour printing without stopping at every swap. From a cost point of view there are two sides to it: on one hand it saves your time and your interruptions, because the machine swaps the filament itself; on the other hand every colour change means a purge block that gets thrown away, as we said in the waste section. So if you go for the Combo, build one simple habit from the start: reduce the number of colour changes per layer at the design stage, and colour stays a gain rather than an extra cost.
Common mistakes in cost calculation
- Relying on volume instead of weight: two parts of the same size can differ in cost by a factor of two, depending on infill and the number of walls. Always take the grams from the slicer.
- Forgetting supports: a model at a bad angle can have supports heavier than the part itself. Change the print orientation before you change your price.
- Ignoring the failure rate: if one print in ten fails, your true cost is at least 10% higher. Price on that basis.
- Pricing specialty filaments like ordinary ones: wood, carbon and sparkle filaments consume more nozzles, more patience and more finishing time.
- Leaving the spool exposed: filament that absorbs moisture gives you popping, weak layers and a rough surface. Store spools in a sealed box with a desiccant, especially in summer.
- Leaving no margin for a reprint: the customer usually asks for a change once they see the first sample. Count that copy from the beginning.
A practical summary
Here is a complete formula you can work with from today:
Cost = [(grams ÷ 1000) × price per kilogram × 1.10] + [(watts ÷ 1000) × hours × price per kilowatt] + (machine depreciation per hour × hours) + the value of your time + a failure margin
Make yourself a simple table with three columns: grams, hours and filament type, and log every print. After twenty prints you will know your real cost per gram and per hour with no guessing. Start with an economical PLA until your settings are locked in, then move to specialty filaments when you have a clear reason: heat, stiffness or looks.
Everything mentioned here — filaments, plates and machines — is available from us with delivery to all Iraqi provinces and cash on delivery, so you can start with the right numbers from the very first spool.
