What counts as custom 3D printing?
A custom 3D printing service makes a part to your specification. It might be a bracket for a shelf you built, a case for a circuit board, a replacement knob, a prototype of a product idea or a set of gifts with your design on them. The fabricator prints it for you, usually on a desktop printer, and may clean it up, sand it or paint it depending on what you agree.
That is different from buying something that already exists. On PrintCommons, a fabricator can offer a finished copy of a published design at their own price. That is called a Make. A custom order starts from your job instead: you find a fabricator, describe what you need, and agree an offer before you pay.
What can I get made?
Printing suits shapes that are awkward or expensive to make any other way: curved housings, brackets with odd angles, parts with internal channels, one-off fixtures, small runs of the same part. It is good at single items and short runs, because there is no tooling to pay for.
It is less good at some things. A printed plastic part is not as strong in every direction as a machined one, because it is built in layers. Very fine detail, tight fits and parts that sit in heat or sunlight all depend on the machine and the material. A fabricator can tell you whether your idea suits their printer. If it does not, they may suggest a different process, or point you toward a different kind of fabricator in the directory.
What does a fabricator need from me?
Enough to be sure they can make the thing you have in mind. At minimum:
- A 3D model, or measurements and photos if you do not have one. If you need a model made, say that clearly, because designing is separate work from printing.
- The size, with units. Say whether the model is in millimetres or inches.
- What the part does. Holding weight, taking knocks, living outdoors, touching skin or food: each one changes the right material.
- How many you want, now and possibly later.
- When you need it, and whether that date can move.
- Whether you will collect it or want it posted.
The more of this you give in the first message, the fewer rounds of questions it takes. If you are unsure how to describe the file, how to find and hire a local 3D printing service covers the preparation step by step.
How does quoting work on PrintCommons?
You message the fabricator from their profile or the machine or service they list. They ask what they need to know, then send an offer with a price, the scope and the timing. You pay on PrintCommons, and you follow the job on the order page. Keep the agreement and the updates there. The how it works page explains what happens to your payment and your order from that point.
Read the offer before you accept it. It should say what you are getting: the material, the size, the finish, the quantity and the date. If something you discussed is missing, ask for it to be added. A clear offer protects you both.
What decides the price and the wait?
Nobody can give you a fair price without seeing the job, but these are the things that move it:
- Material. Common plastics are cheaper than engineering ones, and resin is a different process again.
- Size and print time. A tall, dense part occupies a printer for hours.
- Supports and cleanup. Overhangs need support material, which has to be removed and can mark the surface.
- Finishing. Sanding, priming and painting are labour, and they often cost more than the printing.
- Quantity. A few copies at once are usually cheaper each than separate orders, but not always, because the machine fills up.
- Design work. If the fabricator has to model or repair your file, that takes time.
- The queue. A fabricator with a full week of prints ahead cannot start yours tomorrow.
Wait time is the same story. Ask how long it will take counting from the day you pay, and what happens if a print fails halfway through.
Where do I start?
Pick two or three fabricators in the directory that list 3D printing and send each the same short description of the job. If a design for what you want already exists, look in the marketplace first. A Make might be the quickest way to get it. Your first order is easier if you read how to prepare your first local pickup too.