Custom 3D printing: how to choose a supplier

Compare custom 3D printing suppliers on seven things: whether they choose the technology to suit the part, which materials they actually print, whether the quote is broken down into time and material, whether they review your model and tell you what is wrong with it, what lead time they commit to, how they handle confidentiality, and whether the unit price falls with quantity. Price per part is the last criterion, and without the other six it is not comparable.

The custom 3D printing market is uneven. A €1,000 desktop machine, a small workshop with five printers and a European online platform with dozens of manufacturing partners all sit side by side. All three will make your part and all three will send you a number. What follows is what turns that number into a comparable quote.

Criteria at a glance

1. They choose the technology to suit the part

The first question a supplier should ask is not "how many pieces" but "what does the part have to do". An indoor electronics enclosure, a gasket and a facade bracket are three different briefs, even if they look similar in size.

Most functional-part jobs should end up on FDM printing, because it is the most versatile and the cheapest. But if you need fine detail, a smooth surface or a watertight wall, FDM is the wrong choice and you should hear that before you pay. We cover the differences in FDM vs SLA.

A good sign: the supplier tells you when their technology is not enough for your part.

2. A material range they can justify

"We'll print it in plastic" is not an answer. In practice the gap between PLA and ASA is tens of degrees of heat resistance, 55 °C against 93 °C according to filament maker Prusa Polymers (PLA, ASA). A PLA part in a car parked in summer sun will deform; an ASA one will not.

Ask for the specific heat resistance figure and whether the material is UV stable. If the supplier does not have those numbers to hand, they are probably not selecting a material at all, just printing with whatever is loaded. Our materials overview with the numbers is in Which material to choose for 3D printing.

3. A quote broken down into time and material

The price of a 3D print has two components: machine time and material consumed. When you get a single number with no breakdown, you cannot tell whether you are paying for slow print settings or needlessly dense infill.

For reference, our price list works with a rate of €1.80 to €3.00 per hour of printing plus material from €0.04 per gram. Converted to weight, that is roughly €0.16 per gram for small parts under 50 g, €0.12 for medium ones and €0.09 for parts over 250 g. On production runs we can get below €0.07 per gram. The minimum order value is €10 excluding shipping.

Other suppliers' numbers will differ, the point is that they can be compared. We break this down in The cost of 3D printing.

4. Model review and manufacturability feedback

This is the criterion that most separates a workshop from a remote print farm. A supplier who simply drops your model into a slicer and hits print will also produce a part with a wall so thin it cracks the first time a screw is tightened.

What to expect: a check that the mesh is watertight, a warning about walls thinner than two nozzle widths, a suggested part orientation relative to the load direction, and a note on where supports will sit and what surface they will leave. With us the basic file check is free; repairing broken models is a separate service at €15.00 / hr.

How to prepare a model so the check finds nothing is covered in How to prepare a 3D model for printing.

5. A lead time that comes with conditions

"Within a week" is only usable when you know what it is counted from. From the enquiry? From quote approval? From delivery of the corrected model?

Ask what could push it back too: waiting on a material the supplier does not stock, or the need to print a test piece. We usually send a quote including the delivery date within 24 hours of the enquiry; the full order flow is set out on How it works.

6. Confidentiality and what happens to your data

If you are sending the model of a part that is not on the market yet, an NDA is an entirely normal request and the supplier should have no problem with it. Follow-up questions worth asking:

• How long do you keep my files and where?
• Will you use my part as a portfolio example? (The answer should be "only with your consent.")
• Will you print the same part for someone else?

With online platforms that route work through multiple manufacturing partners, check how many hands the model passes through before it reaches a printer.

7. How the price falls with quantity

There is no tool in 3D printing, so the unit price does not drop as dramatically as it does with injection moulding. But it should drop, through better bed utilisation, batch setup and the model preparation being written off across more pieces.

If you get the same unit price at 5 and at 200 pieces, the supplier is not thinking about batches. At larger quantities it is also worth asking whether small-batch production or a different technology altogether is a better fit. We cover where the crossover sits in 3D printing versus traditional manufacturing.

Local workshop or large online platform?

Put simply: when you need someone you can talk the part through with, and who will tell you your brief does not make sense, look locally. When you need a specific technology nobody local has, use a platform.

Checklist: what to send with an enquiry

To keep quotes comparable, send every supplier the same thing:

1. The 3D model: ideally STEP (it carries exact geometry), with STL as a supplement.
2. Quantity and whether this will be a repeat order.
3. Environment: indoors or outdoors, operating temperature, UV, contact with chemicals or food.
4. Load: what the part holds, pulls or presses; where something rubs against it.
5. Critical dimensions: which tolerances must be met and how tightly.
6. Surface: is the part visible, or hidden inside an assembly?
7. Deadline: when you need it and what happens if it arrives late.

Seven bullet points take five minutes and save you a round of questions and answers with every supplier you approach.

How we handle it

We are a small workshop focused on FDM printing and 3D modelling. That means the part you send is looked at by the same person who then prepares it for printing, and if the brief is a poor fit for FDM, we say so before we make it. The basic file check is free, quotes usually go out within 24 hours, and on larger batches we propose a volume discount automatically.

Examples of completed work are in our references. If you have a model, or just a description of the part, send us an enquiry, you will get a price and a date.