Once again, we have the folks from 3D Supply Guys here with more tips on functional filaments! They did the testing, so you don’t have to!
3D filament manufacturers are continuing to develop more [fun]ctional materials
While ABS and PLA are still the de facto standard for FDM 3D printers, various alternatives have been released with properties that impact the realism, surface quality, strength, and color of models. This new generation of 3D printer filament materials is unique, and in some cases requires that you pay close attention to print settings and hardware limitations of your machine. For this article, we’ll look at four very different materials: Bronze PLA (a PLA base combined with bronze powder), Carbon Fiber PLA (a PLA base combined with milled carbon fiber strands), Conductive PLA (a PLA base combined with black conductive carbon), and Thermo Temperature Changing PLA (PLA combined with temperature sensitive color changing additives).
How are these different filaments made?
Bronze PLA is not just bronze in color. It’s a PLA combined with actual metallic bronze powder. The result is a print that will ultimately look and feel as if it were made of bronze, once polished. The overall effect is in part due to the filament’s added weight; at several times the density of standard PLA, it simply feels more like metal. Carbon Fiber PLA is another alternative filament to hit the market. Mixed with small, chopped carbon fiber strands, this material offers incredible rigidity, structural characteristics, and great layer adhesion. With Conductive PLA, a whole new world in electronic design awaits. Thanks to the addition of conductive carbon particulate, you can 3D print low voltage electronic circuits for basic items such as LEDs and sensors. Looking at Thermo Temperature Changing PLA, you have a plastic that will change color in tandem with changes in temperature. There are actually several color combinations available from different manufacturers, each with slightly different properties.
It’s important to note that when using filaments like Bronze and Carbon Fiber PLA, there are actual particles in the filament that may negatively impact your printer. Metallic particulate in filament of any kind is well known for wearing the inside of standard brass nozzles faster than traditional PLA or ABS. While you can still use brass nozzles, it’s recommended that you consider switching to an upgraded wear-resistant nozzle.
Bronze PLA (PLA + fine bronze powder)
Bronze PLA is one of the first simulated metallic 3D printing filaments to hit the market from manufacturers such as ColorFabb and eSun. In most cases, it combines PLA with a certain percentage of fine bronze powder, making it around four times heavier than standard PLA. Accordingly, when held or touched, it feels more solid and dense than plastic. However, it does require extensive post processing to take full advantage of the available potential. Once printing is completed, Bronze PLA will typically have a dull, grainy appearance. This is where some experimentation comes into play – users have reported a wide range of polishing and sanding techniques to produce various degrees of metallic sheens. The goal is to enhance the appearance of the bronze particulate throughout the object. Using 120-180 grit sand paper is a good first step to remove the print lines, depending on the print resolution. Next, employ higher sandpaper grit values (240-320) for fine-level detail work. Finally, top it off with a pass of 600 grit sandpaper. Once sanded, use a copper polish on cloth and rub it along the surface of the object. This copper polish will help produce the bronze luster. Bronze PLA does not require a heated build plate and can be printed between 195 to 220°C. Users have also reported greater success with increased flow rates between 1-10%.
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Carbon Fiber PLA (PLA + chopped carbon fiber strands)
Carbon Fiber PLA is extremely popular for its high-strength characteristics. For the purpose of this article, we took a look at Proto-pasta’s filament, and their approach of combining PLA with 15% carbon fiber strands. When rolled into a filament spool Carbon Fiber PLA is somewhat brittle, so be sure to unwind and feed it through your printer carefully. Known for its rigidity, it’s the perfect choice for drone building, remote control cars, propellers, support structures, and frames. As long as it’s used for applications where excessive bending is not required, Carbon Fiber PLA is a go-to choice for housings, shells, and other protective casings. Some users have reported that Carbon Fiber PLA works great with larger nozzles; particularly .5mm and higher on standard direct drive extruders— however, the filament is designed to work with and will flow freely on all nozzles .4mm and larger. Carbon Fiber prints just like standard PLA and flows best between 195 to 220°F. No heated bed is required, with good adhesion properties directly on build plates. If you find that your Carbon fiber PLA adheres a little too-well to your print bed, the manufacturer recommends a flexible build plate be used to help release your print after completion.
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Conductive PLA (PLA + conductive carbon black)
Conductive PLA offers a number of options for very basic, low voltage applications. While there are a variety of manufacturers offering conductive PLA, for purposes of this article we looked at the variety offered by Proto-pasta. It can be used for LEDs and sensors as well as low current Arduino projects. In terms of conductivity, Conductive PLA will accommodate anything that can be run through a 1K resistor, as long as the conductors are designed properly. Offering decent layer adhesion and minimal warping, a heated print bed is not required, and print temperature ranges typically fall within 215 to 230 °C. The material is fairly strong, but should not be depended on for extreme mechanical applications. As with many filaments it can break with recurring bending, and care should be taken to ensure that model thickness is robust when not being used for low-level circuitry. Typically, prints become are more rigid when they are greater than 2mm thick. Importantly, conductive PLA can also stick to regular PLA. This is particularly useful if you’re interested in printing basic circuits on top of standard PLA plastic.
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Thermo Temperature Changing PLA (PLA + proprietary additives)
Thermo Temperature Changing PLA is relatively new to the 3D printing scene, offering an array of color changing capabilities. For one particular variety, when subject to temperatures of about 84° F or more, the material takes on a different color hue. To date, some of the available color variations include opaque grey to transparent, blue green to yellow green, grey to white, and purple to pink. The material offers print characteristics similar to PLA, with no heated bed required. Temperatures range from 200 to 210°C, but will (as always) depend on your printer’s specific capabilities. It’s important to note that thermo temperature changing filament is indeed different from color changing PLA, which changes based on UV light rather than temperature. This PLA is ideal for novelty items, toys, signs, cell phone cases, and other consumer oriented products that can take advantage of visual changes based on temperature.
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Filaments of the future are already here
New and innovative materials available to 3D makers are bound to captivate new audiences with exciting, cool, and creative possibilities. Remember, experimentation is key and every filament not only requires different printer settings, but also attention to the nuances of the material. While filament manufactures include recommended print temperatures, flow rates, and other settings, you’ll need to discover the best combination of options to use on your machine. In the case of metallic PLA filaments, nozzle upgrades offer prolonged life and reduced wear. Properties for a particular filament are even likely to vary between brands, as manufactures have different ways of producing their respective materials. For example, eSun’s Bronze PLA may feature different additives, powder, and pigments then ColorFabb’s. This can affect print characteristics and performance. In order to reduce the chances of print failure and improve print quality, make sure you test new materials before committing to a large-scale print. Don’t be afraid to push the envelope and learn the various print limits and behaviors for each filament. Jamming, clogging, and other issues are part of the process – not our favorite part of the process, but a great way to learn and understand your filament’s performance limits.
A summary guide of the above information can be found below:
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What’s your favourite filament? Comments? Post them below!
Let us know if you have any questions or feel free to share your experiences when printing with the material covered in this blog!
About the Author
3D Supply Guys is a premium supplier of 3D Printers & Scanners, 3D Filament, and 3D Printing Supplies. Whether you’re an individual or organization, we’re here to help. Our hand selected product line includes products from the industry’s leading manufacturers, and is available with free shipping for all orders over $100. We also offer a variety of discounts for educational institutions. Visit us today at https://www.3DSupplyGuys.com.
If you’re interested in learning more about filaments, check out 3D Supply Guys’ previous articles here:
*To help develop the information in this article, Proto-pasta provided 3D Supply Guys with a complimentary 1 kg spool of conductive filament for testing purposes.