Every printed product is a material decision before it is anything else. The same shape in three different polymers behaves like three different products: one warps in a car, one goes brittle in the sun, one survives both and costs more. If you are buying a printed piece — or commissioning one — it is worth understanding the handful of materials that actually matter and what each one is good at.
PLA: the default, and a good one
PLA is the most widely used 3D printing polymer, and there is a reason for that. It prints with excellent dimensional accuracy, holds fine detail, comes in an enormous range of colours and finishes, and is derived from plant starch rather than petroleum. For anything decorative or indoor, it is usually the right answer.
Its limitation is heat. PLA begins to soften at a relatively low temperature — low enough that a car parked in full summer sun is genuinely a risk, and a dishwasher cycle is fatal. It is also comparatively rigid, which means it will crack rather than bend when something finally gives.
Good for: display pieces, sculptures, vases, decor, desk organisation, most indoor household items.
Not for: anything that lives in a car, near an oven, or outdoors in direct sun.
PETG: the practical workhorse
PETG sits between PLA and the engineering polymers. It tolerates more heat, it is considerably tougher, and it flexes before it fails rather than snapping. It is the same family of plastic as a drinks bottle, which tells you something about its chemical and moisture resistance.
The trade-off is finish. PETG is slightly less crisp on very fine detail than PLA, and it can be a little glossier. For a functional piece this is invisible; for a highly detailed miniature it matters.
Good for: kitchen and bathroom pieces, things that get handled daily, brackets and holders, anything that needs to survive a knock.
Not for: situations needing the very finest surface detail, or sustained high heat.
ASA and ABS: for outdoors and heat
ASA is the material to reach for when a part has to live outside. It is specifically formulated to resist UV degradation, which is what turns most plastics chalky and brittle after a summer on a balcony. ABS is its close relative — tougher and more heat-tolerant than PLA, but it yellows in sunlight, so outdoors it is the weaker choice.
Good for: garden and balcony pieces, automotive interior parts, anything that will sit in sun or heat.
Not for: the cheapest possible indoor decorative object — you are paying for properties you will not use.
TPU: when it needs to bend
TPU is a flexible polymer, effectively a printable rubber. It is what you want for grips, bumpers, gaskets, phone cases and anything that has to absorb an impact rather than resist it. It is slower and fussier to print, which is reflected in the price of parts made from it.
Nylon and composites: the engineering end
Nylon, polycarbonate and fibre-filled composites are where printed parts stop being an alternative to injection moulding and start being an alternative to metal. They are strong, stiff and heat-tolerant, and they are the right call for jigs, tooling, functional brackets and short-run mechanical parts. They also demand much more from the machine and the operator, which is why they sit in the custom side of the business rather than the general catalogue.
How to choose, in three questions
Will it get hot? A car interior, a windowsill in July, anything near a hob or a dishwasher — that rules out PLA immediately and points at PETG, ASA or better.
Will it live in sunlight? UV is the quiet killer of outdoor plastic. If the answer is yes, ASA is the honest choice and everything else is a compromise.
Does it need to survive being dropped? If the piece is functional and will be handled every day, toughness beats surface finish. PETG or better.
If the answer to all three is no — which it is for most decorative and indoor pieces — PLA gives you the best detail, the widest colour range and the lowest environmental cost.
What we use, and why we will tell you
Compl3x specifies material per design rather than running everything in one polymer, because the right choice for a kitchen holder is not the right choice for a display piece. If you are buying something for a specific environment — a car, a greenhouse, a bathroom — ask us before you order and we will tell you what that piece is made in and whether we would produce it differently for your use.
If you are commissioning a functional part, material selection is part of the design conversation rather than an afterthought. That is covered under our manufacturing services.
