We Are Learning 3D Printing Through Our Personal Experience…
The topic of recycling and reusing various everyday plastic objects, and not only the material of failed 3D prints, has been often mentioned by the many projects for filament makers that we’ve seen popping out . They however do not go into much detail regarding the options to recycle plastic and focus mostly on the creation of filament from plastic pellets instead or the reuse of old and failed ABS or PLA prints to make new filament. In fact we believe that what the filament maker machines should actually focus on is the recycling and reusing of old plastics from various things that we use everyday instead of throwing away. By recycling and reusing plastic bottles and other plastic products that have ended their lifecycle and we don’t need anymore we can really save on cost of filament and we can actually help the nature from plastic waste. The problem of reusing old plastic that did not come from filament for the 3D printer is that there are may types of plastics and not all of them could be reusable for 3D printer filament and then there is also the risks for your health associated with the recycling of some plastics or their usage afterwards. So as we’ve said it is not an easy topic and you need to go into detail of what can actually be done, what is possible and what is not, what is safe and what is not. It is easier however to just use the word recycle as marketing and not go into detail about the possible usage scenarios of your product for actually recycling and reusing different plastic “waste” as 3D printer filament.
When looking at the various plastic products that we use and have around us we should know that they could be made from many different plastic types and it is not a good idea to mix different plastics when trying to recycle them and turn them in a filament for a 3D printer. There is a standard classification used for plastics for everyday objects that defines 7 different categories of plastics and if you look at the label or usually the bottom of a product made from plastic you should see a mark showing the respective category of plastic used (like the PET bottle for mineral water on the phpto above). Do note that if something is made from multiple plastic pieces, then there is a chance that different plastics might be used for different parts (the cap of a plastic PET bottle for example). These 7 symbols are being used in most countries, though there could be some variations, to categorize plastic and are called recycling codes. There are similar codes for other things such as batteries, paper and metal, but we are not going to be talking abut them here. If you have been around 3D printing for a while you probably already know that there are much more variations of different plastics used for 3D printer filament and these are not found in the commonly used plastic categories as many of them were actually designed to either replace common plastic types, were adapted or even made especially for use with 3D printers.
Out of the seven main types shown above the most used and recycled materials in everyday life are the 1 and 2, but they both are not commonly found in 3D printing filament. One of the most common material used for 3D printing is ABS and unfortunately it does not have its own category – it falls under the number 7, though sometimes we can see the recycle triangle with ABS written inside or under it and no number or the number 7. Out of the first 6 categories only number 1 (PET) and number 6 (PS) have high melting temperatures above 200 degrees Celsius which makes them very suitable for use with 3D printers, the other one is ABS that is under category 7. The number 6 however is not commonly recycled and reused and is in fact not very suitable for 3D printing filament besides the high melting temperature it has, as it is considered possibly dangerous to your health as it may leach styrene. In fact styrene is also used in some of the number 7 plastics such as AS, ABS and SAN… this is precisely why you get warned to print using ABS filament in well ventilated are, because the fumes from heated ABS plastics are not very safe for breathing. The number 7 category is considered the most health unsafe because of the Polycarbonate (PC) plastic that initially was mostly labeled under 7, but is currently less used due to the concerns of it being dangerous to health due to the possibility of it leaching BPA (Bisphenol A), there are come concerns about BPA contained in some plastics under category 3 and 6 as well, so they may not be considered as food safe as well. When talking about food safety even PET plastics that is most commonly used for plastic bottles for drinks is said that may leach Antimony, another not so safe chemical used in the production of the plastics, especially when exposed to higher temperatures.
So after a bit of research about safety of plastics, their recycle-ability and features we end up with just two types of plastics that could be viable for recycling and reusing as being relatively safe for 3D printing purposes – ABS and PET. Polyethylene Terephthalate abbreviated as PET or PETE is easily obtainable as we can get it from plastic bottles for various drinks and some other containers. The material has a high melting point at about 260-280 degrees Celsius, so it could be a bit of a challenge for 3D printing without mixing it with something else when making it into a filament for 3D printing. We have actually recently tested a PET-based filament from Innofil3D and were quite happy with the results. So recycling PET plastics for use as a 3D printer filament sounds like a good idea, though the topic needs some research and experimentation with existing filament maker machine (you would also need a grinder for the plastics).
Recycling ABS plastics could also be a bit challenging, although ABS is a commonly used plastic type and should be easily found used for various thing around you. The reason for that is that ASB plastic used for the cases of various electronic devices often contains additional hazardous flame retardants. So it could turn out to be harder to obtain safer ABS plastics from everyday items to recycle and remake into filament for your 3D printer. One surprising source of safe ABS plastics is the plastics used in cars such as the one the dashboard and other plastic elements are made from as they do not seem to contain the hazardous flame retardants we have mentioned. But then again obtaining plastic elements from cars that are meant to be scrapped might not be so easy for everyone, so you could look for other alternatives.
We do have plans on getting a filament maker machine in the future precisely to be able to experiment in recycling everyday plastic items and trying to reuse them as 3D printer filament. As we have already mentioned this is what is the more interesting function of these machines than to recycle failed prints (you need to have a lot of those to make sense) or to buy cheaper plastic pellets and make filament yourself. Recycling old plastics into filament has its drawbacks such as limitations to the colors you can get for the filament material, usually clear or semi-transparent colors for PET and various colors for ABS, but mostly black or grey and white, though many other colors might be available as well – depending on the source of plastic products. There are also some possible health risks, but you should be pretty safe if you do what is recommended when working with the specific plastic. Interestingly enough there are even some companies that have started selling 3D printer filament made from recycled plastics, and while good for the environment, buying such filament defies the very purpose of getting a filament maker machine to recycle and make cheaper filament yourself while turning some of your personal waste into something useful.
Time to share our first impressions from printing with the new Innofil3D EPR PET 3D printer filament that we told you about last month. The recommended print temperature of the Innofil3D EPR PET filament is somewhere in between 200 and 230 degrees Celsius, so we have tested in that whole range to see what will be the results. The printing speeds that are recommended are between 40 and 100 mm/s and we had no trouble printing at the highest point with smaller details and higher resolution. The EPR PET filament should be printable without heated build platform, but if HBP is available the recommended temperature to use is between 75 and 85 degrees Celsius. We were able to print 3D models just fine without turning on the heated build plate of the printer, though the use of HBP might help prevent warping of edges when doing large and more complex prints the same way as with PLA. The glass transition temperature of the ERP PET material is listed as 62 degrees Celsius or maybe slightly higher than the 55 degrees of an average PLA, though some PLA filaments may go as high as up to about 65. This is the temperature when the material starts to soften, so similar to PLA this filament is also not suitable for use when high ambient temperatures are expected.
We are using our trustworthy MakerBot Replicator 2 3D printer for printing and are doing our typical test using a simple 3D model of a house (Monopoly style) printed at various extruder temperatures with 0.2 mm layer height as well as printing a 1×1 cm cube with 0.1 mm layer height to compare the accuracy of the printed part to that of the same model printed from PLA. Innofil3D is positioning the EPR PET filament as an alternative to the most common PLA filament for 3D printers and although they are pretty similar in terms of specifications. Though Innofil3D notes that there might be some areas where their new filament could perform slightly better than normal PLA making the EPR PET an easier to print material and with better resulting prints.
What you can see on the image above is the results we got from our simple house test prints using various temperatures of the extruder. At 200 degrees Celsius the house did not print like that, but it seems that the temperature is too low for proper interlayer adhesion, so while we were removing the house from the printer build platform it started to cleanly break at various layers. At temperature of 210 degrees Celsius there were no longer any problems with interlayer adhesion like with the lower temperature and the best quality results we got were in between 210 and 215 degrees. Going with temperature of 220 degrees Celsius and higher the resulting 3D prints were still very good, but visually they had some small imperfections compared to the result we got at about 210-215. So for best quality and to avoid interlayer adhesion issues the 210-215 degrees Celsius seems to be working best with the Innofil3D EPR PET filament, at least for us on our Replicator 2 3D printer. The other test for the shrinkage of the material after printing has shown that the ERP PET 3D filament has very minimal shrinking just like PLA does, so that makes it suitable for more accurate prints and less problematic in terms of possible warping unlike when using ABS for example.
What is our conclusion about the ERP PET 3D printer filament after doing some test prints with it, well we consider it as a very good alternative to traditional PLA filament. It has very similar properties and ease of use, provides very good printing quality and even has some advantages. It prints well at higher extrusion speeds for smaller details, but good PLA does that as well, in terms of resolution and appearance it performs like a good PLA filament and probably better than cheaper PLA filaments. There is a bit of a catch however in terms of good layer adhesion and good quality, you need to use the right printing temperature to get these, if you don’t then you may end up with worse results than with PLA. The best working temperature for ERP PET seems to be a bit lower than what we are used to working with with most PLA filaments, that is if you really want to get the best quality and avoid problems with layer adhesion, but don’t go too low either. In terms of strength the ERP PET filament has some advantage over PLA, though it may not be as strong as material as ABS for example and with a price that is just slightly higher than that of normal PLA the Innofil3D EPR PET filament could really end up being an interesting alternative to traditional PLA filaments.
3devo NEXT 1.0 is a new professional and affordable solution to creating your own 3D printing filament or recycling materials and failed prints into filament. The company just launched their crowdfunding campaign on Kickstarter with a goal of 50000 Euro. There are already some technical information about the filament maker and there is a pretty good looking and working prototype shown. But until the device is finalized there should be some improvements and more features hopefully available. The project looks promising, though there is more to be desired at this stage, but if you are interested in getting yourself a filament maker machine, then you would probably want to keep an eye on this one as well.
NEXT 1.0 Key Features:
– Superior filament quality
– Ease of use
– Unparalleled performance
– Unlimited 3D printing filament;
– Environmentally friendly solution to recycle failed 3D prints, plastic bottles and many other plastic items that would irresponsibly end up in the trash
NEXT 1.0 Technical Specifications:
– Dimension (with hopper): 506x216x540 mm (LxWxH)
– Dimension (no hopper): 506x216x448 mm (LxWxH)
– Color: Blank anodized / black powder coated
– Input material: ABS, PLA and other materials
– Operating temperature: Up to 500 degrees Celsius
– Extruder screw: Hardened nitride steel with compression zone
– Extrude diameter: 0,5 – 3,0 mm
– Diameter sensor accuracy: 43 micron
– Capacity: 1kg/hour
– Power: 110 / 240 V
– Connection: USB, Stand-Alone filament extruder
There is talk about recycling materials and turning them into brand new filament with this filament maker, however the device does not come with a grinder to help you in making the plastics into small pieces just like pellets. This is actually one of the drawbacks that many filament extruders have as they are most interesting for users to be used for recycling and making new filament instead of buying plastics pellets and making your own filament. Another important moment is the price, it seems that the regular price of the device will be 1850 Euro, so actually not so affordable compared to other alternatives especially if you will have to get a separate plastic grinder as well. Aside from the early bird units that will offer lower price and earlier availability, normal Kickstarter backers as well as people that may order the device after the crowdfunding campaign is over will have to wait to at least March 2016 to get their device.