What is pla for 3d printing


Ultimate Materials Guide - Tips for 3D Printing with PLA

Overview

Polylactic Acid, commonly known as PLA, is one of the most popular materials used in desktop 3D printing. It is the default filament of choice for most extrusion-based 3D printers because it can be printed at a low temperature and does not require a heated bed. PLA is a great first material to use as you are learning about 3D printing because it is easy to print, very inexpensive, and creates parts that can be used for a wide variety of applications. It is also one of the most environmentally friendly filaments on the market today. Derived from crops such as corn and sugarcane, PLA is renewable and most importantly biodegradable. As a bonus, this also allows the plastic to give off a sweet aroma during printing.

  • Low Cost
  • Stiff and good strength
  • Good dimensional accuracy
  • Good shelf life
  • Low heat resistance
  • Can ooze and may need cooling fans
  • Filament can get brittle and break
  • Not suitable for outdoors (sunlight exposure)

Hardware Requirements

Before 3D printing with PLA make sure your 3D Printer meets the hardware requirements listed below to ensure the best print quality.

Bed

Temperature: 45-60 °C
Heated Bed Optional
Enclosure not required

Build Surface

Painter’s tape
PEI
Glass plate
Glue stick

Extruder

Temperature: 190-220 °C
No special hot-end required

Cooling

Part Cooling Fan Required
Fan Speed: 100%

Best Practices

These tips will help you reduce the chances of common 3D printing issues associated with PLA such as stringing, oozing, or under-extrusion.

Fine Tune the Retractions to Prevent Oozing

One of the most common problems with PLA is oozing. Since the filament flows relatively easily when compared to the other materials, it has a tendency to continue flowing during travel movements at the end of a segment. This creates strings or hairs on your part, and dialing in your retraction settings is the best way to combat this behavior! Different brands of PLA and different printers may need slightly different retraction settings, so you may need to experiment to find the best value for your printer. Simplify3D added a very useful feature in Version 4.0 that can help with this, by allowing you to quickly try dozens of different settings, and then look at the final part to determine which one worked the best on your specific setup. For example, you could setup two vertical pillars which are printed side-by-side to evaluate stringing when moving back-and-forth between each pillar. Then go to Tools > Variable Settings Wizard and choose how you want to adjust your settings during the print. For example, you could try a different retraction distance for each 20mm section of the print and then pick the value that works best in the end. For more tips on how to reduce stringing and oozing, be sure to check out our Print Quality Guide which contains an entire section dedicated to this issue: How to Reduce Stringing and Oozing.

Optimize Your Cooling Settings

Cooling is one of the most important aspects of printing with PLA. Having a dedicated part cooling fan makes a huge difference in the quality of the printed parts. The freshly extruded plastic needs to cool down below the glass transition temperature as quickly as possible. This will prevent the plastic from stringing and producing other artifacts. We recommend setting the fan to 100% throughout the print, except for the first 1-2 layers where you want to form a strong bond with the print bed. Simplify3D also includes a useful option on the Cooling tab of your process settings that can automatically reduce the print speed for small parts, ensuring that the layers have sufficient time to cool. This can greatly improve the print quality by allowing the layer to solidify before printing the next layer on top of it. This setting can be found on the Speeds tab of your process settings.

Choose the Correct Extruder Temperature

This is a great tip for any filament, but is especially useful for PLA which often contains different combinations of additives depending on the manufacturer. These different additives can lead to variations in printing temperature between 190-230 degrees Celsius. If you are not printing at the right temperature this can lead to several print quality issues including oozing, stringing, and under-extrusion. PLA can also be combined with different fills like metal, wood, and fiber that give it different characteristics than a standard homogeneous PLA. These may require different settings or even different hardware. Be sure to check with the manufacturer of your filament to verify the optimal temperature to use for your specific filament. If you have trouble with stringing, try reducing this temperature by 5-10 degrees, which will help prevent the excess oozing. If you’re struggling with under-extrusion, try increasing the temperature by 10 degrees so that the material flows more easily through the nozzle.

Pro-Tips

  • Using a fan that cools the 3D printed part from all directions is highly recommended. Many popular 3D printers have community-designed attachments that can be printed and retrofitted onto your machine to improve the cooling airflow.
  • Increasing the number of perimeter outlines for your PLA prints will create a strong bond between each layer, creating stronger parts that are less prone to breaking.

Get Started with PLA

Now that you are ready to start printing with PLA, here’s a bit more information to help you get started. Start thinking of project ideas by reviewing our common applications, try out one of the provided sample projects, or find a new filament to try from our list of popular material brands.

Common Applications

  • Test and calibration items
  • Dimensionally accurate assemblies
  • Decorative Parts
  • Cosplay Props

Sample Projects

  • LA Spring Motor, Rolling Chassis
  • G – Clamp
  • Storm Trooper Helmet

Popular Brands

  • Polymaker PLA, PolyMax, PolyPlus
  • ColorFabb PLA/PHA
  • Hatchbox PLA
  • eSun PLA
  • Filamentum PLA

All you need to know about PLA for 3D printing

Published on August 19, 2019 by Carlota V.

PLA, also known as polylactic acid or polylactide, is a thermoplastic made from renewable resources such as corn starch, tapioca roots or sugar cane, unlike other industrial materials made primarily from petroleum. Due to its more ecological origins this material has become popular within the 3D printing industry, we have begun to see it in medical applications and in food products.

To get to know more about this material, we have prepared a complete guide about PLA filament for 3D printing. What are the best printing parameters? How does PLA filament differ from the ABS filament? Who are the manufacturers? When is it best to use it and for what type of applications?

The production of PLA plastic

PLA was created in the 1930s by the American chemist Wallace Carothers, most recognised for the development of nylon and neoprene in the chemical company DuPont. But it wasn’t until the 1980s that PLA was finally produced for use by the American company Cargill.  

This thermoplastic polymer is produced by fermenting a carbohydrate source such as corn starch. In this case, the natural product is ground to separate the starch from the corn, mixing it with acid or lactic monomers. With this mixture the starch is broken into dextrose (D-glucose) or corn sugar. Finally, glucose fermentation produces L-lactic acid, the basic component of PLA.  This material is considered a non-Newtonian pseudoplastic fluid. This means that its viscosity (flow resistance) will change depending on the stress to which it is subjected. Specifically, PLA is a fine cut material, which means that the viscosity decreases as you apply stress.

PLA filament in 3D printing 

PLA filament has gained wide acceptance within additive manufacturing partly because it is made from renewable products and also because of its mechanical properties. It is often the preferred choice for beginners in 3D printing as it is a very easy material to work with. This material, considered a semi-crystalline polymer, has a melting temperature of 180ºC, lower than ABS filament, which starts melting between 200ºC and 260ºC. This means that when printing with PLA, the use of a heated printing bed is not necessary, and the closed chamber is not a necessity either. The only drawback is that the PLA filament has a higher viscosity which can clog the print head if you are not careful.

This filament does not have the same mechanical properties as the ABS filament; the second is much more resistant and flexible. However, PLA has greater resistance to heat, so it is often used in the food industry. Even so, its is often recommended to work with it if the project does not have major mechanical complexities, as it is much simpler. For example, PLA does not require complex post-processing. It can be sanded or treated with acetone if required and the supports are usually very easily to remove. There may be some problems with the first layer of this material, therefore it is recommended to add adhesive tape onto the printing tray to facilitate its detachment once the piece is finished. 

Is it truly sustainable?

In recent year, the sustainability of PLA filament has been questioned. Possibly because the term biodegradable, which is often used to refer to this filament, has been leading to confusion. Indeed, the material is created from renewable materials that you find in nature, however it does not make this material necessarily biodegradable. This material can decompose, but only under certain aerobic conditions. For example, PLA can degrade rapidly when subjected to industrial composting, otherwise it can take up to 80 years to decompose in the open, becoming like other plastics, a plastic pollutant. If you are interested in finding out more about the environmental impact of PLA filament, we interviewed three experts who gave us their exclusive insights on this subject.  

PLA is made from renewable materials such as corn starch

The main manufacturers of PLA filament

Being one of the most popular materials within 3D printing there are many manufacturers today. The Austrian company WeforYou, a developer of polymers and sustainable solutions, is among the most prominent. The German company Evonik focused on the development of PLA for the medical sector, the American company NaturaWorks large producer of biopolymers, and the company Corbion, based in the Netherlands, focused on the development of high-performance resins with PLA. 

The price of the PLA filament may currently vary depending on the colours and characteristics you are looking for. Hybrid filaments such as wood, conductors, etc. can cause the price to go up. In general, the price of a desktop filament is between 20€ – 70€ per kilogram. There are also 3D printers capable of producing pellets, which could drastically reduce the price of the material.

PLA is one of the most popular materials in the 3D printing industry, especially for extrusion technologies

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