PLA Filament: The Complete Guide for 3D Printing
PLA (Polylactide) is the most popular filament for FDM 3D printers and ideal for beginners. It is made from renewable raw materials like corn starch, prints at low temperatures and hardly warps. In this guide, learn everything about properties, optimal print settings and when PLA is the right choice.
What is PLA?
PLA (Polylactic Acid) is a biodegradable thermoplastic derived from plant-based raw materials. Unlike petroleum-based plastics like ABS, PLA is produced by fermentation of sugar from corn starch, sugar cane or other plant materials.
PLA belongs to the group of aliphatic polyesters and is characterized by the following properties:
- Low print temperature (180–220 °C)
- Low warping tendency
- Good detail accuracy and surface quality
- Hardly any unpleasant odors when printing
- Biodegradable under industrial composting conditions
Technical Properties in Detail
| Property | Value | Meaning for Printing |
|---|---|---|
| Print Temperature (Nozzle) | 180–220 °C | Low → fast heating, energy-saving |
| Bed Temperature | 0–60 °C (optional) | Often no heated bed needed, reduces warping |
| Glass Transition Temperature (Tg) | ~60 °C | Not for heat-exposed applications |
| Tensile Strength | 50–70 MPa | Sufficient for most hobby applications |
| Density | 1.24 g/cm³ | Light, good filament yield per kg |
| Impact Resistance | Low | Brittle, not for mechanically stressed parts |
| UV Resistance | Low | Not recommended for outdoor applications |
Pros and Cons of PLA
✅ Advantages
- Easy to print (ideal for beginners)
- No toxic fumes, little odor
- Heated bed optional (saves energy)
- High detail accuracy
- Biodegradable (industrially)
- Large color selection available
- Inexpensive compared to other filaments
❌ Disadvantages
- Low heat resistance (from ~60 °C)
- Brittle, not impact resistant
- Not UV resistant (fades, becomes brittle)
- Not suitable for outdoor applications
- Not food-safe without post-treatment
- Can degrade over time through hydrolysis
Optimal Print Settings for PLA
Base Settings (Reference Values)
These values are starting points – adjustments may be needed depending on printer and filament manufacturer:
| Parameter | Recommended Value |
|---|---|
| Nozzle Temperature | 200–215 °C (first layer: +5 °C) |
| Heated Bed | 50–60 °C or off (with adhesive) |
| Print Speed | 40–80 mm/s (outer walls: 30–50 mm/s) |
| Fan (Part Cooling) | 100% from layer 2 (first layer: 0%) |
| Retraction (Direct Drive) | 3–6 mm @ 40–60 mm/s |
| Retraction (Bowden) | 6–8 mm @ 40–60 mm/s |
| Layer Height | 0.1–0.3 mm (0.2 mm standard) |
Troubleshooting: Common Print Errors
Stringing
- Lower temperature by 5–10 °C
- Increase retraction (test in 0.5 mm steps)
- Adjust retraction speed
- Dry filament (if wet)
Warping (Corner Lifting)
- Enable heated bed (50–60 °C)
- Use bed adhesive (glue stick, Magigoo)
- Add brim or raft as adhesion surface
- Avoid drafts (enclose printer)
Poor First Layer Adhesion
- Adjust Z-Offset (nozzle closer to bed)
- Clean print bed thoroughly (IPA)
- Print first layer slower (15–20 mm/s)
- Increase bed temperature
PLA vs. Other Filaments: When to Use What?
| Property | PLA | PETG | ABS | ASA |
|---|---|---|---|---|
| Print Difficulty | ⭐ Easy | ⭐⭐ Medium | ⭐⭐⭐ Hard | ⭐⭐⭐ Hard |
| Heat Resistance | ~60 °C | ~80 °C | ~100 °C | ~95 °C |
| UV Resistance | ❌ No | ⚠️ Medium | ❌ No | ✅ Yes |
| Impact Resistance | ❌ Brittle | ✅ Good | ✅ Good | ✅ Good |
| Outdoor Suitable | ❌ No | ⚠️ Limited | ❌ No | ✅ Yes |
| Printing Odor | ✅ Little | ✅ Low | ❌ Strong | ⚠️ Medium |
| Typical Application | Decor, prototypes | Functional parts | Housings, mechanics | Outdoor, automotive |
Decision Guide: Which Material When?
- Choose PLA for: Decorative objects, figurines, prototypes, models, indoor applications without heat
- Choose PETG for: Functional parts, housings, mechanical parts, light outdoor use
- Choose ABS for: Heat-resistant parts, post-processing (acetone smoothing), automotive
- Choose ASA for: Outdoor applications, UV exposure, weather-resistant parts
Application Areas for PLA
Ideally suited for:
- Prototyping: Quick concept models and design studies
- Decorative objects: Figurines, vases, art objects, jewelry
- Architectural models: Buildings, landscapes, city models
- Tools and fixtures: Templates, brackets (without heat)
- Cosplay and props: Costume parts, props
- Educational materials: Models for schools, universities
- Spare parts (indoor): Buttons, covers, adapters
Not recommended for:
- ❌ Parts in cars (heat + UV)
- ❌ Outdoor furniture or garden decor
- ❌ Food contact (without special post-treatment)
- ❌ Mechanically heavily stressed parts (prefer PETG/ABS)
- ❌ Applications above 50 °C continuous temperature
Storage and Care of PLA Filament
PLA absorbs moisture from the air, which can cause print problems:
Symptoms of wet filament:
- Bubbles during extrusion (audible hissing)
- Stringing and poor surface quality
- Brittle filament (breaks easily)
- Inconsistent extrusion
Proper storage:
- In sealed bags with silica gel packets
- Dry box with dehumidifier for active spools
- At room temperature, protected from sunlight
- Humidity <50% ideal
PLA Variants and Special Filaments
Standard PLA
Classic PLA in various colors. Inexpensive, reliable, ideal for beginners.
PLA+
Modified PLA with improved impact resistance and reduced brittleness. Slightly more expensive, but more robust.
PLA Silk/Satin
With glitter particles for silky, shiny surface. Ideal for decorative objects.
PLA Matte
Matte, non-glossy surface. Hides layer lines better than standard PLA.
PLA Translucent
Translucent, ideal for LED housings, lampshades, light objects.
PLA-CF (Carbon Fiber)
Reinforced with carbon fibers. Higher stiffness, but abrasive (hardened nozzle required).
Wood-Fill PLA
Mixed with wood fibers. Wood look and feel, easy to sand and stain.
Metal-Fill PLA
With metal powder (copper, bronze, brass) for metallic look. Can be polished.
Our PLA Filaments in the Shop
Frequently Asked Questions (FAQ)
Is PLA biodegradable?
Yes, but only under industrial composting conditions at 60+ °C and high humidity. In household waste, in nature or in home compost, PLA practically does not degrade. PLA is therefore more environmentally friendly than ABS or PETG, but not a "miracle material" for disposal.
Can I print PLA without a heated bed?
Yes, PLA adheres to cold print surfaces with glue stick or special PEI/glass plates. A heated bed (50–60 °C) does improve adhesion and reduces warping on large prints.
Is PLA food-safe?
Pure PLA is theoretically food-safe, but 3D-printed objects have microstructures where bacteria can settle. Without special post-treatment (epoxy resin sealing), PLA prints are not recommended for food contact.
Why does my PLA print become brittle and break?
Possible causes: (1) Filament has absorbed moisture → dry. (2) Old filament spool (PLA ages through hydrolysis) → use fresh filament. (3) Print temperature too low → increase temperature.
Can I post-process PLA?
Yes, PLA can be sanded, sawed, drilled and glued (super glue works well). Unlike ABS, PLA cannot be smoothed with acetone. Alternative: epoxy resin coating or XTC-3D for smooth surfaces.
How do I dispose of PLA prints?
In Switzerland, PLA goes in normal household waste, not in organic waste or recycling. Industrial composting facilities usually do not accept PLA, as it degrades too slowly.
Related Guides
- PETG Filament: Properties and Applications
- ASA Filament: The Outdoor Specialist
- The Perfect First Layer: Troubleshooting Guide
- Properly Drying and Storing Filament
Note: The information in this guide is based on typical properties of PLA filaments and general 3D printing knowledge. Specific values may vary depending on manufacturer and product line. Always consult the technical data sheets of the respective filament.