What can be replaced
Plastic parts that break long before the rest of the product are what 3D printing suits best: dials and knobs on cookers and washing machines, battery covers, clips and hooks on furniture and in cars, feet under furniture and appliances, lids for jars and boxes, brackets and holders that have snapped, gears in kitchen machines, and parts the manufacturer no longer sells. A part like that often takes under an hour to print, and a replacement in PETG is often tougher than the original in brittle plastic.
What they have in common is that they are small, do not sit in heat and do not carry a heavy load.
What not to 3D print
No 3D print in PLA or PETG should sit where a failure could hurt someone or damage something: brakes, steering, child seats, climbing gear, parts that carry a person's weight, or parts connected to mains electricity. Nor do the materials take high heat. PLA softens at around 55 °C and PETG at around 70 °C, so neither belongs in an engine bay, an oven, a dishwasher or on a dashboard in the sun. Parts that have to hold water under pressure, or come into contact with food, are not suitable either. The terms of sale say what applies.
In a car, parts inside the cabin that carry no load and sit out of direct sun are fine: panel clips, holders, lids for storage compartments and knobs. Choose PETG.
Finding the file
Many replacement parts have already been drawn. Search the model sites MakerWorld, Printables and Thingiverse for the product's name together with "replacement", "spare part" or "3d print", and you will often find several versions. Parts for IKEA furniture, common kitchen machines and car models are the most common. Read the comments: other people who have printed the part say whether it fitted and which material they used.
How to find models, choose the file and order is set out step by step in the guide No 3D printer? How to get a model printed.
Drawing the part yourself
If the part is not available to download, it can be drawn, and simple parts such as a knob, a foot or a bracket are a good place to start. Programs such as Tinkercad, Onshape and FreeCAD are free for private use, and Tinkercad runs in the browser.
Measure the broken part with callipers, not a ruler. Parts that have to slide into something need about 0.2 mm of clearance on each side, and a hole for a screw is drawn 0.2 to 0.4 mm larger than the screw. Walls should be at least 1.2 mm thick. How much clearance each kind of fit needs is in the guide Tolerances and fit. Draw in millimetres and save as STL, or as STEP if the program can, so the dimensions travel with the file. If the fit has to be exact, it is wise to order one copy first and try it before you order more.
We do not design whole models to order, but if you have a file that almost fits, or a simple part that needs adjusting, we can in some cases help free of charge when the print is ordered from us. Contact us and describe the part, with measurements and a photo if you can.
Choosing a material
PETG is the right choice for most replacement parts. It is tougher than PLA, gives a little instead of cracking, copes with moisture and takes heat up to around 70 °C, so it suits brackets, clips, knobs and anything that lives in a garage, a bathroom or a car. PLA suits parts that stay indoors and carry no load, such as a foot under a lamp or the cover of a remote control, and gives sharper detail. The comparison is in the guide PLA or PETG.
On the order page, the quick pick Functional gives PETG with a 0.20 mm layer height and 15 % infill. A part that carries a load does well with 30 % infill or more, and you can change that yourself.
What it costs
Most replacement parts are small, weigh a few grams and take under an hour to print, so they land near the lowest price for a print. If you order a few copies of the same part, the price per copy comes down, so it can pay to take two of a part that wears. Larger parts, such as a lid or a long strip, cost more because they take more material and more time. Several parts for the same appliance go in one file and are ordered together, see the guide Several parts in one file. The price includes VAT and is shown before you order, and shipping is added at the checkout. How the price is worked out is in the guide What does 3D printing cost.
Order the part
Upload the file on Order a custom 3D print online. You see the model and its dimensions straight away, so compare them with the broken part before you go on. Choose PETG, a colour and the quantity, and see the price. The print is normally sent within 7 days as a tracked parcel, anywhere in Sweden.