PLA vs PETG vs ABS: Which Filament Should You Choose?

The Great Filament Debate

Walk into any 3D printing conversation and you'll hear the same three acronyms repeated endlessly: PLA, PETG, and ABS. These are the three most widely used FDM filaments, each with dramatically different properties, printing requirements, and ideal use cases. Understanding the differences is one of the most important things a new maker can learn — choosing the wrong material wastes filament, time, and often results in parts that fail prematurely in service.

The good news is that the choice is rarely mysterious once you know what each material is optimised for. Let's break them down systematically so you can make an informed decision for any project.

PLA (Polylactic Acid) — The Beginner's Champion

PLA is the most widely printed filament in the world, and for good reason. It's derived from corn starch or sugarcane, which gives it a relatively low melting point and a characteristic sweet smell when printing. It sticks well to most bed surfaces, rarely warps, and is available in an enormous range of colours — including beautiful silk variants and ultra-flat matte formulations that hide layer lines remarkably well.

The significant weakness of PLA is heat resistance. Its glass transition temperature is around 60°C, which means a part left on your car dashboard on a hot Australian summer day will soften and deform. In Melbourne in February, a black PLA bracket in direct sun can reach failure temperature within minutes. PLA is also brittle compared to other plastics — it tends to snap under sudden impact rather than flex. For decorative prints, models, prototypes, and indoor items that won't experience heat or mechanical stress, PLA is ideal. For anything functional, read on.

PETG — The All-Rounder for Australian Conditions

PETG is our most-recommended material for Australian makers who need something tougher than PLA. Its heat resistance extends to around 80°C, it's significantly tougher and more impact-resistant than PLA, and it has natural UV resistance that makes it far more suitable for outdoor use under Australia's intense sun. PETG prints at higher temperatures than PLA (230–250°C hotend) but doesn't require an enclosure, making it accessible on virtually any printer.

The trade-off is that PETG is stringier and can be more finicky to tune. It bonds very strongly to some bed surfaces—too strongly on smooth PEI, which can tear the coating upon removal. Use a thin glue stick layer on smooth PEI, or better yet, switch to a textured PEI surface for PETG. Once dialled in, PETG is extremely reliable. 

ABS — The Old Workhorse with Modern Rivals

ABS is a high-heat, high-impact thermoplastic that has been used in manufacturing for decades — LEGO bricks, car dashboards, and power tool housings are typically made from it. It has excellent heat resistance (glass transition ~105°C), can be sanded smoothly and acetone-vapour polished to a glossy finish, and is genuinely tough under mechanical stress.

However, ABS has a serious reputation for being difficult to print. It shrinks as it cools, which causes severe warping and layer cracking without a heated enclosure. It also releases styrene fumes during printing — a known respiratory irritant that requires proper ventilation or enclosure filtration. Many experienced makers now recommend ASA as a modern alternative to ABS — it has similar mechanical properties with the addition of genuine UV stabilisation, and warps slightly less. See our ASA vs ABS comparison for the full story.

Making the Right Choice

The simplest decision framework: use PLA for anything decorative or non-critical. Use PETG for functional parts, outdoor items, or anything that will be in a moderately warm environment. Reserve ABS (or better, ASA) for parts that need high heat resistance or are going outdoors permanently. If you need something even tougher, look into engineering grade filaments like Nylon and Polycarbonate — but be prepared for a significantly more demanding printing experience. For most Australian makers, 90% of prints can be handled by PLA and PETG alone.