Choosing a filament

PLA vs ABS vs PETG

Three filaments that cover most of what an FDM printer is ever asked to do. They are not interchangeable, and the difference is not ‘quality’ — it is what the part has to survive. Here are the measured numbers, the settings each one needs, and how to tell which one your part wants.

See the Numbers Get Parts Printed

PLA 56 MPa tensileABS 96 °C HDTPETG 8.0 kJ/m² impactAll three printed on our floor

One sentence each

What Each One Is For

PLA — the easy one

Stiffest of the three on paper (56 MPa tensile) and by far the easiest to print: no enclosure, an unheated bed is acceptable. It gives that up in heat — it softens from about 53 °C, so a PLA part left in a parked car is a lesson, not a part.

ABS — the tough, hot one

Holds its shape to 96 °C and takes a hit (20 kJ/m², the highest here). The price is process: it wants 95–110 °C of bed and an enclosure, because it warps and splits when it cools unevenly.

PETG — the middle that works

Most of ABS’s toughness (8.0 kJ/m²) and most of PLA’s manners — no enclosure needed. It bends before it snaps (18 % elongation), which is usually what you want from a bracket that gets dropped.

Measured, not claimed

The Comparison Table

	PLA	ABS	PETG
Tensile strength	56 MPa	38 MPa	48 MPa
Impact, Izod notched	3.5 kJ/m²	20 kJ/m²	8.0 kJ/m²
Elongation at break	4 %	15 %	18 %
Heat deflection (HDT)	53 °C	96 °C	70 °C
Density	1.24 g/cm³	1.05 g/cm³	1.27 g/cm³
Nozzle temperature	190–220 °C	220–250 °C	225–250 °C
Bed temperature	0–60 °C	95–110 °C	60–85 °C
Enclosure	Not needed	Required	Not needed
Minimum wall	0.8 mm	1.0 mm	0.8 mm
Overhang limit	55° from vertical	45° from vertical	50° from vertical
Unsupported bridge	30 mm	15 mm	20 mm

Pick by the failure you fear

How to Choose in One Question

Will it sit in heat or sun?

Then not PLA. ABS at 96 °C or PETG at 70 °C both survive a closed car or an enclosure; PLA at 53 °C does not.

Will it be dropped or flexed?

Then not PLA either — it is the stiffest and the most brittle (4 % elongation). ABS and PETG both bend first.

Is it a model, jig or fit check?

Then PLA, every time. Best dimensional behaviour, no enclosure, no warping, and the fastest route from file to part in your hand.

Questions

PLA, ABS and PETG — Common Questions

Which is the strongest of the three?

It depends what you mean by strong. PLA has the highest tensile strength at 56 MPa, but the lowest impact resistance at 3.5 kJ/m² — it resists being pulled and shatters when struck. ABS is the opposite: 38 MPa tensile but 20 kJ/m² impact. For a part that gets handled, ABS or PETG will outlast PLA even though PLA wins the tensile number.

Can I print ABS without an enclosure?

You can start one. Finishing it flat is the problem: ABS shrinks as it cools, and cooling unevenly is what lifts corners off the bed and splits layers up the side of tall parts. It needs 95–110 °C of bed and still air. If you do not have an enclosure, PETG gets you most of the toughness with none of that.

Is PETG just better than PLA?

For functional parts, usually. For printing, no. PETG is stringier, less forgiving on retraction and sensitive to moisture; PLA prints cleanly on almost anything. If the part is visual or dimensional, PLA is still the better answer.

Do these need drying before printing?

PETG does, in practice — wet PETG strings and prints with a rough, bubbled surface. PLA and ABS are less sensitive but both take up moisture over months in open air. Any of the three will print better out of a dry box.

Which do you print production parts in?

Neither PLA nor ABS, mostly. Production parts on our floor go in PETG, nylon, carbon-fibre nylon or polycarbonate depending on load and temperature — PLA and ABS are prototype and fixture materials here. Tell us what the part has to survive and we will tell you which we would run it in.

Go deeper

The Full Data on Each

Not Sure Which One Your Part Wants?

Send us the file and what it has to survive. We print in all three every week and will tell you which we would run it in — including when the answer is none of them.

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