PLA, PLA+ and PLA Pro: Differences and Filament Choice

What is it PLA filament?

PLA (polylactic acid) is the easiest filament to work with for FDM/FFF 3D printing. It produces clean features and a smooth surface with minimal risk of deformations. The trade-off is lower impact resistance and softening around 55–60 °C, making it a poor choice for warm environments.

When PLA is the best choice

• Decorative models and figurines — fine detail and surface finish are its strengths.

• Visual prototypes - quick tests of shape and dimensions.

• Lithophanies - predictable behavior and consistent "transparency" at thin walls (depending on colour).

When does PLA start causing problems

• Clips, snap-fits, live hinges - PLA is more fragile and often snaps.

• Parts in a warm environment - at temperatures around the glass transition (Tg) softening and deformation begins, especially under load.

What is it PLA+ filament and how is it different?

PLA+ is a trade name without a single standard - the "plus" depends on the manufacturer. It usually means a modified PLA with better interlayer adhesion, lower brittleness and slightly higher impact resistance, with almost the same ease of printing.

What you usually gain with PLA+

• Less layer splitting in functional parts.

• More predictable behavior for snap-fit items.

• Similar surface quality and close printing temperatures to PLA.

Important clarification

Two different PLA+ filaments can behave differently: one being a real upgrade, the other being a minimally changed formula. If the part is critical, test with a small clip/hook or standardized test pattern instead of relying on the label alone.

PLA Pro Filament – who is it for and when is it worth it?

PLA Pro is generally positioned as "engineered PLA". The goal is noticeably better strength and interlayer adhesion, often with formulas for higher flow rate and better behavior in high-speed printing. This is a logical choice when PLA+ is not enough but PETG/ABS is not desired.

Typical benefits

• More reliable functional parts: holders, brackets, snap-fit housings.

• Better resistance to repeated loading (hinges/clips), according to the specific formula.

• More stable results at higher speeds on "high-speed" runs if the hotend and cooling are adequate.

Possible compromises

• Price above PLA/PLA+.

• Narrower setting window: often requires 5–15 °C higher nozzle temperature and more careful fan control on large parts.

PLN filament (PLA-N) – separate class or "another PLA"?

PLN (also known as PLA-N) is typically a PLA-based "next generation" biopolymer developed as a material for prototyping and functional applications. The idea is a behavior close to PLA, but with better mechanical and sometimes better thermal characteristics. In some variants, annealing is provided to increase heat resistance (only if the manufacturer describes it in the technical data).

What to expect from PLN in practice

• Less brittleness and more "working" elasticity in clips.

• Good interlayer adhesion, useful for 3+ perimeters and thinner walls.

• Annealing possible with some of the PLN/PLA-N formulas, but with the risk of dimensional changes.

Recommended print settings

The settings below are indicative. Always follow the specific filament manufacturer's recommendations.

Nozzle temperature (reference)

• PLA: 190–220 °C

• PLA+: 200–225 °C

• PLA Pro: 205–230 °C

• PLN/PLA-N: 200–215/225 °C according to the series

Surface temperature

• PLA / PLA+: 0–60 °C (50–60 °C helps for first layer)

• PLA Pro / PLN: 40–65 °C (often more stable with heated surface)

Cooling (fan)

• Small features and fine walls: 80–100% after first layers.

• Solid functional parts (especially PLA Pro/PLN): often works better at 60–90% for better interlayer adhesion.

Speed (starting values)

• PLA / PLA+: 40–80 mm/s

• PLA Pro: 60–120 mm/s as a start; "high speed" series can do more, but require flow and a stable printer

• PLN: 40–80 mm/s; increase gradually

Adhesion and deformation tips

• Clean the surface with isopropyl alcohol.

• In case of problems, use PEI surface or glue stick.

• For large flat bases, add a brim of 3–5 mm.

• Avoid drafts (air conditioner/open window).

• For tall and narrow models: slower first layer and stable adhesion are more important than high speed.

Which material should I choose?

The choice is made most easily by three questions: will there be bending/impact, will there be heat, and how important is ease of printing.

• If the goal is appearance and fast printing: PLA or PLA+.

• If functional parts are needed without switching to PETG/ABS: PLA Pro or PLN.

• If there is real heat (e.g. a car in the sun): PLA-like materials often soften around 55–60 °C and the risk remains; then PETG/ABS are safer.