Designing 3D Prints That Sell
The small design choices — thickness, a stable base, real tolerances, built-in personalization — that decide whether a product delights or gets returned.
Your return rate is decided at the design stage. A wall a hair too thin, a base a touch too small, a decorative spike that snaps the first time someone picks it up — none of those are manufacturing problems. They are numbers you chose. Put your part’s numbers in and see which ones need changing.
Design check · five rules, your numbers
1 to fix
Fits the machine
Largest side 120 mm — under the 255 mm limit, so it prints as one piece.
Two share a bed
Copies print side by side, so a run gets the quantity discount — up to 30% off labour.
Something will snap
1.2 mm is under 1.5 mm. Thin lettering, spikes and antennae are what break in a customer’s hand. Thicken it or make it a separate piece.
Stands up
Height 120 mm on a 70 mm base — stable on a desk.
Parts will fit
0.3 mm clearance — enough to go together without forcing, not enough to rattle.
The bed check is the same function the checkout uses to decide the quantity discount. Upload the real file and we check it against the machine for you, then print one sample to hold before you list.
The design mindset
Design the one that survives the hand, reads in a thumbnail, and carries a name.
In practiceClean geometric forms read at thumbnail size. Fussy detail disappears in the photo and snaps in the hand.
The rules behind the check
- Handle it
- Swords, antennae, thin lettering, delicate spikes — these are what break. At least 1.5 mm, thicker at stress points, or a separate piece we fit for you.
- Stand it up
- A lamp base that tips, a vase that wobbles, a stand that rocks — all come back. A flat, wide, weighted base protects your reviews quietly.
- Fit it
- Anything that goes onto something else lives on tolerance: 0.2–0.5 mm of clearance, and dimensions from the manufacturer’s spec, not from your own device.
- Round it
- Rounded edges are safer, stronger, and print cleaner. And no small detachable parts on anything for young children.
- Pair it
- A part narrow enough for two on a bed gets the quantity discount on every run. Twenty millimetres can be worth a quarter of the labour.
The courier is not your problem: every order ships in protective packaging chosen for the part. Your job is a product that is sturdy once the box is open.
Design for the material and the value
A phone case must be TPU, a part near heat PETG or ABS, a display piece can be PLA — design knowing which one it prints in (the live rack is in the materials guide). And build the personalisation in from the first sketch: a name plate, an engraved date, a swappable text panel. It is the design decision that most raises what you can charge.
Designing something people will handle every day? Materials for everyday parts plots heat against toughness for every plastic we stock.
FAQ
Keep features at least 1.5 mm thick, thicken stress points, and give the piece a stable base. Then order one sample and handle it before you list.
It depends on size and use, but avoid anything under about 1.5 mm on a part that will be handled. Thin lettering and delicate protrusions are the usual failures.
Up to 255 mm on any axis in one piece. Larger products are split into parts that key together, and we assemble them for $1 a part if you ask.
Design a customisable element — a name plate, an engraved area, a text panel — into the model from the start.
Hold one before you sell a hundred.
Upload the file, see the price in seconds, and order a single sample. Every order after it is printed, checked and shipped under your name.
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