Recycling 3D Prints and Waste Plastic into Filament (PET & PLA)

[@DrDFlo]

♻ Mechanical recycling is very challenging. It takes a lot of time and expensive equipment to produce a material that would cost a fraction if just purchased new. Let me know in the comments what societal and technological innovations are needed to make recycling of failed prints and waste plastics more economical.

[@bigbomb5904]

I have a bag of pla filament failed prints. I have been looking for a long time for someone to take a prints so it doesn't go to waste

[@anthonyleggio4877]

what if you melted the plastic into a sheet before reclaiming it to get a more uniform size and shape?

[@loneepicz]

As an optician im very interesting to see if you can recycle cellulose Acetat frames. The goal would be to get uniform pellets to heat mold plates to cut out new frames. For the community could you test a cellulose Acetat spool because it is rare on that market. On the manufacture side i could read that it is possible to recycle PA so my question is while i saw that you have a printer from Formlabs, could you recycle prints with this and could make a PA spool out of it. Hope for more content like this special if you could try cellulose Acetat🙏🏻

[@OneHappyCrazyPerson]

So how do you get the small particles out ? Like sand or shavings for example, things like that will definitely clog a nozzle

[@Master_Tiger_44]

This could be a good way to recycle of you can get a donation spot

[@FilamentStories]

This is hands down the most thorough and clearly explained video on why recycling 3D printed waste is time consuming, challenging and expensive both in energy costs and products required to produce a useable resultant filament. The added degradation of the plastics from multiple heat cycles and the need for virgin resin to make a product that prints reasonably well is another factor that many people don’t often consider. Thank you for covering so well all the considerations and steps required to produce an at home, Makerspace or other consumer-based recycled 3D printer filament. It is a wonderful thing that so many people are passionate about wanting to recycle their 3D printing waste. It's just much more difficult to do than most people realize. Someday hopefully there will be a more straightforward path or more companies like Recycling Fabrik in Germany, who accept and recycle 3D printer scraps. I’ll be sending people your way to watch this video.when get questions in the future. Many thanks!

[@MitchDavis2]

I work at a filament company. This video is spot-on. I get asked daily by people if they can send me scraps to turn into filament, and the answer isn’t very quick or easy to explain, but you absolutely nailed it in this video. Our biggest sales are the lowest-cost filament. We’ve even made recycled PETG filament, but cost always has a bigger influence than sustainability when it comes to sales. You’re the first person I’ve seen that accurately explains why it’s not as simple as “adding old prints into a melter and making filament” and you even went as far to explain why it typically needs to be extruded TWICE. In the business world, labor = $$$, which makes recycling very difficult to make when competing with virgin resin pellets. I’ll be sending everyone who asks me about recycling over to this video. Thanks for taking the time to do this!

[@DrDFlo]

Glad the video resonates with your experience on the industrial scale! I wish this video wasn't turning into being such a black pill on the recycling process

[@matildo4ka7]

You guys are blind, you don't see an opportunity that is right in front of your noses.

[@MitchDavis2]

@@matildo4ka7 what do you mean? We’ve made recycled filament, but it cost more so it didn’t sell

[@chilloxik]

​@@MitchDavis2which country are u sourcing your virgin pellets from? Once you tell me I can check the prices of raw vs. rPET. I think if you can find cheaper rPET abroad it'll still give you a sustainable company label plus you'll sell cheap recycled material to your final consumer. Pultrusion here is the small scale option especially now when you can just use your old Creality 3d printer and reuse it as a pultrusion device. It's $180 for a recycling device, ta-da. Yes, it's long process, but if you work with your community well and they provide you with PET bottles, you can offset some filament costs plus educate your community.

[@matildo4ka7]

@@MitchDavis2 for the large scale recycling you cannot compete with India and China anymore. You can sit and wait for them to come up with the solutions and they will make equipment cheaper than Filabot btw. I'll wait for that ;)

[@kevingauthier7973]

I worked in injection molding over 40 years and I worked with plenty of regrind materials. I kept looking for you to make a mistake but you hit everything on the head good job. Those are all the same issues all recyclers deal with . I worked at an injection molting factory once that advertised a product as recycled materials but used virgin because it was cheaper than recycled. Also there is a difference between pre consumer and post consumer plastic.

[@beldron]

I worked in a recycling plant for PET and HDPE and it was interesting to see that you have faced some of the difficulties in small scale which the big recycling process brings with it.

[@ActionBOX]

Thanks for the shoutout Dr! We were very happy to help you out with our SHREDII 😃 Looking forward to more future collaborations 😁

[@Enjoymentboy]

This was a great video. Looking at my own PLA waste I can say that supports are about 80% of it is and this makes me think that a perfect use for 100% recycled PLA with 0% virgin pellets added would be for a dual filament 3D printer where the recycled PLA is only used for support material. The physical properties really become irrelevant for supports and colour consistency wouldn't matter either.

[@DrDFlo]

Great idea! If the model is purely aesthetic, then you could also use the recycled material for the infill and new filament for the perimeter and outside layers.

[@SianaGearz]

@@DrDFlo Infill should ideally not be load-carrying, as it's extruded faster and with less bonding strength. It's there mostly as internal support for roof layers. I actually do slicing tricks to reduce the extrusion thickness of both infill and support. Infill, it depends, i don't necessarily like going much below nozzle width on that, but on support i go absolutely wild, and it comes out fluffy soft and very easy to remove because it's so fragile.

[@stevecade857]

Model dependent but I think the filament swap priming would create more waste than just sticking with the primary filament for the supports, not counting the extra time and energy required.

[@AndrewHelgeCox]

​@@stevecade857 Would this be a problem with a dual head printer rather than a filament swap single head one like the Bambus?

[@stevecade857]

@@AndrewHelgeCox The waste on the Bambu comes from changing filament and flushing it through ready to print. A dual head wouldn't need the flushing just priming so it's ready to print.

[@AllsFree]

This is possibly the best/most informative video on filament recycling. This is great, a complete honest 10/10.

[@halfstep67]

If one can't afford a reclaimer, a Chocolate Lab would be a great alternative. A Lab can chew up anything.

[@DrDFlo]

😂

[@stevecade857]

I don't think the Lab gets hot enough to extruder a filament though so good luck recovering the pellets.

[@rtmfb]

@@stevecade857 I'm not sure how hot they get but they definitely can extrude something.

[@paytonmacdonald1409]

​@@rtmfb thick coils of brown filament

[@ThingsMadeOfOtherThings]

You're a exceptional educator! You pack in so much detail but it all comes across and the explanations are so clearly worded and presented. I'll come back to this video as a reference for anything processing related in future. Thank you

[@Marzec309]

The inconsistent feed of your virgin/regrind material can be improved with a screw that has a mixing section. Also, separate barrel heating zones can help control Feed, Mixing and Extrusion.

[@stevecade857]

The Pelletizer should be direct drive as well just pulling off a free standing or mounted spool. No need for two separate machines.

[@phillupson8561]

Looks like the grinder would be less labour intensive if they changed the design so you had a big hopper at the top, it could grind on the large grinder and drop straight through to the next grinder, with a sieve built in below that (probably angled toward a collection bin) that could deal with the dust and then slide the correctly sized pellets out to the side, that would remove a lot of babysitting from the process. I've always fancied making something like this (on my list of 3000 other projects i'll never get around to it) but seeing this in action definitely gives me some ideas.

[@Arturius_Rex_8]

That would involve extra gearing/axles to run both grinders. This design only requires the one common axle.

[@thenextlayer]

Wow. Most effort on a KZbin video ever. It shows. Great work.

[@Ckpe4]

One of the best recycling videos on KZbin. Thanks a lot. IMHO plastic is to valuable mostly non renewable resource to be town away

[@samuelcarlton6956]

Exceptional video and a masterclass in thorough, yet concise scientific education. Thank you for the time and effort in putting this together.

[@johnmoore5593]

I'm SO thankful you showed this in such detail. I have been very interested in recycling of 3d prints and I'm glad to know that this is not the direction to go in for now. It's simply too low of a return for too high of a cost. I look forward to the day that we have a 3d print recycling service in the Americas.

[@Trust_me_I_am_an_Engineer]

Printerior in St.Louis? 😁

[@johnmoore5593]

@@Trust_me_I_am_an_Engineer thank you. I was not aware of Printerior. I will look to them!

[@theresaflorian5052]

What an extensive process, learned a lot! Thanks

[@gorak9000]

I think you misspelt expensive... $12k for just the reclaimer and peletizer?? And you still need the extruder and the cooling modules, and given the cost of the other 2 parts, I bet their metal box with a bunch of fans inside it sells for $300 each at minimum - wouldn't even want to guess how much they want for the extruder.

[@filagain4137]

@@gorak9000 40K USD for an entire set of filament recycling, so yeah

[@gorak9000]

@@filagain4137 I see no reason why it's so expensive, other than some kind of "greenwashing premium" to say "I recycled my filament" that big companies would pay just so they can put some bs blurb on their website - there's absolutely no reason why that "reclaimer" and "pelitizer" is $12k - there's probably no more than $500 of parts in both of them combined, and even that's probably being generous

[@danialhowe9814]

i think this marks the biggest game changing need in the industry today - once this can be done on a home basis it will be huge

[@jacksonrussell3645]

I used to work at a plastic factory we had a water bath directly infont of the extruder to help with keeping uniform size

[@Mcdonaldrod75]

This video is outstanding, firstly. The main thing is to get consistency for in-flow. Since PET bottles are such a curse, I feel a machine and process totally dedicated to this is worth considering. The flakes melted and compressed into one large sausage, then a machine that just rolls out and stretches sections of it. These are then melted end to end and wound around a spool. Something like that.

[@lap87]

Another banger from the Doctor, love it! was very interesting to see this "at home" setup explained in great detail, today i learned a lot! Would be cool with a follow-up video where you take us through a bigger facility to point out the differences and any other solutions they had to develop

[@DrDFlo]

🤞 Hoping to get out to a molecular recycling facility

[@agmuntianu]

why not use a modified injection molding machine ( basically only the heating chamber and the piston, with a disk that has many 3mm holes ) , to get fairly uniform 3mm "spaghetti" and pelletize that ? instead of 2x grinding + extrusion to 3mm ?

[@rajgill7576]

I'm also wondering why he even has to add virgin pellets in if he's going through the trouble of palletizing the recycle to mat h the density anyway. Just feels like he's choosing to recycle 50% slower for a marginally better product

[@joshuacheung6518]

I wondered the same, then thought about it a bit. How would you load it? How much could you load at once?

[@joshuacheung6518]

​@@rajgill7576to combat thermal degredation.... how much skipping did you do?

[@WitherandFronst]

Incredible detail! Thank you for being so thorough explaining the process end to end.

[@Pooria-jr9yf]

this is great. Thank you. One issue I have with the same shredders that I have in my lab is that the previous residue materials is almost impossible to be removed from between blades so the next material is always contaminated.

[@agepbiz]

This was super interesting and informative. Great video. I have kept my scraps for years for future recycling. Not sure what to do with it yet though

[@petermuller608]

Do energetic recycling

[@subtext9881]

This is quality content and well presented too. Regarding the set of machines, I am somewhat surprised that those are, well, "under engineered". For 17k I expect more sensors and actuators. Adjusting rates by hand is a thing of the past.

[@Slavicplayer251]

could you try melting the shreded prints first into a solid sheet then shred that to create solid pellets/chunks

[@DudleyToolwright]

Very well done as always. The thought organization in the video is outstanding.

[@Uniqueuponme]

Even though the costs are still extreme, the advancement in small scale extruding is amazing. I can see this being a long term cost savings for a universities and maker spaces.

[@hippopotamus86]

But is it really when you factor in the time taken to do this? Buying a spool is probably cheaper than paying someone to run these machines.

[@cnc-maker]

Even on an industrial scale, recycled filament is more expensive than virgin filament. Electricity and time cost a lot of money, and we haven't even discussed the sorting, or the inability to sort most plastics. As presented, the sorting requires human effort, which again, is extremely expensive and prone to error.

[@randallbourque1321]

@@cnc-maker The electricity is a point he did not even mention. Unless you have a very large solar array, your costs can be very high depending on where you live.

[@SynthOSphere]

@@cnc-maker This tells me the price of petrol/oil derived products is still too low. Our societies must learn to make the difficult sustainable choices.

[@rosly_yt]

It all depends on the time efficiency, labor costs, and the spools you're comparing to. Universities and maker spaces both commonly use some amount of free labor, and the price of a kilogram of filament can vary quite a bit, depending on a lot of factors. I've bought $14 spools, and $25 spools, for example. There is an obvious cost savings if you buy bulk PLA and colorants and run these machines with virgin material - if you can get labor costs to around $4/Kg, then you'll beat all but the cheapest filaments in price, and beat everyone in the ability to make custom colors, blends of colors, additive mixes, and so forth, on-site and on-demand. Slant3d, who runs a large 3D print farm, for example, talks about how he makes most of the filament on-site, for better quality and lower price. So a workshop that processes a mix of new and recycled material will beat just buying spools fairly quickly, depending on efficiency and how much filament the organization uses, and some of those savings can be invested into the recycling arm of the operation, which needs a few extra machines and more labor per Kg of product, but if you're going to recycle filament, an existing virgin materials manufacturing facility is a great place to start. Obviously, individual printers - even those who own a dozen machines - don't benefit from this arrangement, but at the order of 100 printers, it starts to make sense. Using the ends of spools as feed for re-extrusion sidesteps most of the problems of recycled filament, especially if the print farm uses mostly a single color for its prints. What really has to happen for filament recycling to make sense at the dozen printer scale is for the process to be basically hands-off to the extent 3D printing is. If I can get 10% extra filament out of every spool I buy, and I go through 100 spools a month, that's $130, minimum, in nearly free filament, and there's some marketing advantage to saying your product is made with recycled material - even if that material never left the factory.

[@itsmisterb]

This video is exacly what I have been searching for months. Inceadible and thorough explanations!

[@greenenko]

Thank you for this video! You have summarized my own experience in this topic and answered all my open questions on why i have inconsistent filament diameter on my diy extruder why filament is not the same as a new one, why do we need compression screws and the most valuable is how to fix all of that issues! Regranulating of the waste and mixing it with a new granules will fix all my problems!

[@shughalonly4724]

Wooowwwww...what an amazingly detailed and informative video ... seriously yoi have cleared every possible doubt ... I am so thankful for your time and effort

[@SeanHodgins]

Very cool, I've wanted to venture into this myself, but I don't think I have enough print waste to make it worth it yet. Its odd they didn't just put a feed directly on the pelletizer to get a perfect cut length for different rpms.

[@N1ghtR1der666]

perhaps the extruder needs a pre-melt phase just before the extrusion phase where a small reservoir is filled with melted ground plastic that forms a kind of buffer, then that melted reservoir can be extruded at a more even rate because its all uniform

[@BennyTygohome]

It looks like a huge pain in the butt, but extremely educational and interesting. The biggest value is education and (although a pain) it looks very interesting to do... Almost even fun 😊

[@AlexanderBurgers]

get yourself a panini press and turn your household recycleable plastics (bottles) into flat pieces first before sending them into the shredder. :) And plastics that are not good for 3d printing can still be turned into feedstock for cnc machining or straight into cast/moulded parts.

[@BodgeEngineering]

Excellent video - you explained so many things that I was struggling with in my adventures with plastic recycling.

[@BennyTygohome]

Your channel is awesome. You explain the process very well.

[@yinfest]

Have you tried compacting the PET bottles and then heating them to melt in a bit more thick/solid object before shredding it? It should give more thick pallets with better flowability and thus be easier for the extruder to operate. I might be wrong but it's worth a shot.

[@matildo4ka7]

You need a very good shredder for this type of action.

[@rodrigoff7456]

Thank you very much for such a sober, educational, and comprehensive overview!

[@kenspaceman3938]

Great educational video…and it trashed my ambitions to recycle my PLA prints, bummer.😢…. BUT, I learned a lot, was really interesting!

[@adrenalinejunky789]

So cool! Recycling prints has come a long ways since the idea was first floating around!

[@Dubtee]

I'm looking into filabot for a start up. Might be my best choice

[@whynotbuildit]

I get so excited when u post !!!

[@CD3DP]

Thank you so much for your efforts and helping to educate us all with your findings. This is hands down one of my favorite pages along side AVE and proper printing

[@loneepicz]

As an optician im very interesting to see if you can recycle cellulose Acetat frames. The goal would be to get uniform pellets to heat mold plates to cut out new frames. For the community could you test a cellulose Acetat spool because it is rare on that market. On the manufacture side i could read that it is possible to recycle PA so my question is while i saw that you have a printer from Formlabs, could you recycle prints with this and could make a PA spool out of it. Hope for more content like this special if you could try cellulose Acetat🙏🏻

[@kymboskreations1914]

Love that piece flying out at 3:02

[@frozendude707]

When making PET bottles in a factory, they start with a preform that looks kind of like a short test tube with thick walls, and then use compressed air in a die in an oven to expand it to the final shape, like a balloon. Would it not be possible to do the same in reverse? Like using a vacuum pump connected to a metal bottle cap and then put it in an oven or perhaps using hot air? Then it should be thicker and easier to granulate.

[@Scozzy_23]

I was not interested in recycling prints, but after this video I am. Maybe not right now but I’m the future, your video was very informative and very high quality, this is the first video of yours I have seen but I am definitely subscribing and you deserve way more subs then you have man.

[@stevecade857]

It's funny as I now am completely of the opposite view. I was interested in personally recycling old print scraps, I'm not now.

[@pmcquay1]

Instead of grinding regrinding and melting the bottles, then pelletizing them and reextrudimg them, could you melt them in an oven in a 3 inch by say 18 inch tray, until you have a bar that is half an inch thick, and then grind that? It might avoid some of the flake problem and let you process the bottles faster.

[@itsmisterb]

Exactly what I was thinking! ActionBox, who he partnered up with for the shredder, also sell a injection molding machine. My idea is he use that machine and use the flakes to make PET ingots. That way it makes it just like a 3d printed part! Of course it adds to the thermal history but such is life

[@matildo4ka7]

You guys are thinking in the right direction 👍👍👍

[@keegan854]

Thanks for the video, this is very interesting stuff. The hollow filament produced by pultrusion is a non-issue -- you just increase the slicer's extrusion multiplier to compensate. I have printed many aesthetic and functional parts from pultruded PET bottles, including all the motion parts for a 3D printer. I agree that the process is quite slow and tedious, but the results are good. If you're dedicated enough, it is pretty much the only truly affordable way to produce filament at home.

[@scheinp9844]

What about recycling Bambu Lab printer AMS poop without those pre-processing? If the result is positive, that might be good investment for tinker.

[@stuartashers]

I would modifie the hopper and auger starting with large screw tapering down to the standard shaft.

[@skylinevspec000]

If anyone wanted to make one of these there is a company in the USA called Surplus center. 1hp AC motors about $150, the gear box is about $130, the bearing pillow blocks about $15 each. Then all you need is a CNC or manual mill cut tool steel grinders. I've seen a guy make the grinders using plate steel with a central shaft that bolts the plates together. This can then be cut on a bandsaw or plasma/waterjet. some sheet metal case. One hell of a lot better than $15000. The entire units are very manual therefor easy to replicate. For the every day person wanting to be as economical as possible when printing.. the entire system if near 18k is way out of range, the ethics of charging education facilities that price is also questionable.. . Good concept, good company idea, greedy implementation and therefor bad environmental impact.. im the bin my left over prints go :( I should note the parts I believe are the same. Ironhorse is a chineese company on alibaba

[@chemistclips]

If your 3d print needs a specific center of gravity or ballast for a weighted base, I feel like pellets could be great to add mid-print as opposed to solid infill. Your QC on the pellets can be pretty loose and you still maintain plastic homogeneity should you intend to later recycle the same print. I'd like to see more investigations using heat (look at the PET droplets falling from the screw! 36:16 Could you get those small enough so they serve as pellets?) or maybe high frequency vibration cutting methods to simplify pellet creation and microplastic reduction? Thanks for sharing your experience and doing the economic calculation for us!

[@Guardian_Arias]

The battle for recycling 3D printing waste continues. Have you looked into melting flakes into pucks? or using melting chamber with a piston to extrude into an inconsistent filament? I do understand the first proposition would degrade the filament further, but it might be worthwhile exploring.

[@stevecade857]

Hydraulic press? Probably better to avoid another high temp heat cycle. The press will generate heat which could help it fuse and be grindable into chucks rather than flakes.

[@sujithkr136]

great video..One thought is ,if you melt the whole bottle to a smaller ,sphere shape,and then perform the shredding process..That way i think you might be able to get rid of the flake shape of pet bottle shreds to much more of a granular shape...

[@zeroblood1435]

why not use pet strip filement from a bottle time in video 27:53 if it's not clear what I mean and use it as pellet? could be an idea to make it easier

[@carrar1113]

Hey you bro I have suggestion about a new subject machine making powder iron

[@gaboxargentina]

AMAZING VIDEO, very educative

[@FabvilleManager]

My makerspace has been looking into how to emphasize the tenets of reduce reuse recycle into our curriculum and your recycling videos have been extremely informative and helpful in setting expectations and planning out our next grant proposals! I really appreciate how un-sensationalized your information was, while still allowing your enthusiasm to come through! Question: Where and how do you store your fillabot machines? Can you run your 3mm pre spool into the peletizer directly or is the speed just way too different? I personally enjoy the recycled brown color, do you make mostly that, or mostly presorted materials?

[@stevecade857]

Very enlightening. Seeing all the scraps I throw in the bin I really wanted to put that waste to good use, probably on prototypes rather than final prints so plastic quality and colour isn't a big concern for me. The time, money and effort required to be doing the 'right thing' is very off putting when a new spool of filament is so reasonably priced. This has really got to be something for 3D printing clubs / shops or education facilities to offer a recycling service. Bring along your scraps (free donation) and purchase recycled filament spools at cheap prices. As long as it makes sense for them financially as well.

[@Digitallifeconcepts]

thank you for the info on the bottle peeler recycle tech. I am interested in this but not at 20hrs per spool of sub par material

[@legofun259]

Just a quick question,Can i use the pultrusion type of extruder( that you demonstrated) and create some roughly hollow filament. Can i pelletize that filament and mix it with the PET flakes to increase the flow and friction in the barrel when extruding the recycled filament so it will be 100% recycled material. Maybe i can even consider adding some new/bought PET pellets to the mix to improve the overall quality. Just curious if all of this might produce some better quality recycled PET filament.

[@becauseican2607]

If you dry the pet flakes with a higher temperature it could pelletize. A pet-bottle in hot water shrinks a lot. So will the flakes.👍

[@GregAtlas]

For the PET bottles, wouldn't it be faster and easier to melt everything down and condense on a tray or some other container and then chop it up so it's not so thin of pieces? That would also help the moisture issue.

[@iandalton887]

Great video! I’m sure you’ve already experimented with this, but have you considered heating the PET regrind slightly to cause it to shrink and take on a more irregular shape? This could potentially increase the friction between the regrind and the barrel.

[@DrDFlo]

The PET regrind was heated for 4 hours at 110C to remove moisture. All the material you saw was after that heating cycle

[@matildo4ka7]

110C is not enough, you need 150C. It will curl PET and that's what you need.

[@matildo4ka7]

I tried this option to regrind PET and you're absolutely right. I'll heat regrind (

[@Naku-SomewhereYouAreNot]

Well, that takes care of any delusions I might have had about doing something with the poop! ;) Excellent conveyance of this bit of knowledge. Thanks so much.

[@macros3798]

Extremely viry nice idea and best filament making idea 💯👌

[@donrozwick7367]

well that explains my problem with extruding my grindings. They usually got stuck and no extrusion.

[@yerry_verse]

Nice video, some things about pulltruders are not correct, and maybe you chose one older model. The other thing is that pulltruded filament can be used to print up to 0.08mm , I'm doing it with my printers, you just need to increase the flow.

[@DrDFlo]

How long would it take for you to make 1kg of filament from (~50) bottles with your pultruder? Please include the time it takes to prepare the bottle and strip it. I had very little practice, so I am curious how quickly an experienced user can process this material.

[@nietofarias]

You could easily make stackable pulltruder machines. Also, I usually prepare 3 or 4 bottles at a time without inflating them, just heating them. The cutting can be done quickly and you can store and pile up the strips. I'm actually producing more filament than I consume myself. The problems are: • Too difficult to set the proper printing parameters to combat crystallization • How to join filaments pieces to make one large 1Kg spool. Since the filament is hollow, it's difficult to join. Filament joiners available now make too weak joints that require wider spools to protect joins from breaking

[@jscancella]

I wish they would make a law to make it easier to recycle plastics. Make all bottles one type of plastic, all containers over a liter a single plastic, etc.

[@cybyrd9615]

​@DaddyVet3Dshut up American the Europeans are talking

[@colinmetzger6755]

​@DaddyVet3Dthat's incredibly untrue. And you only need to look to environmental protections to see it. People and companies polluting the environment should be held responsible and it should not be allowed.

[@BuzzingGoober]

​@colinmetzger6755 and yet the gov allowed the cl0t sh0t to happen and want to eliminate nuclear energy. If you haven't noticed yet, the government is not your friend.

[@AshAshAshAshAshAshAshAshAshAsh]

@DaddyVet3D seat belt law decreased deaths. Air bag laws decreased deaths. Third break light laws decreased deaths. Headrest laws decreased deaths. I’d argue crooked cops who decide the letter of the law is more important then the spirit of the law are what causes more criminals. There are bad policies, like Californias grip laws for ARs but in that situation the professional group (the NRA) didn’t want to show up and help so a bad solution was made. Excluding experts is a problem

[@exposenetworklimited4497]

Ya just what we need more laws that solve nothing! All laws do is make the rich richer period

[@walf6978]

Awesome video! Everything I wanted to know and a whole bunch more that I was happy to learn!

[@RPBCACUEAIIBH]

Plastic bottles shrink when heated. When they shrink, they also thicken. You may be able to shred plastic bottles far easier if you heat them before shredding. Thicker shredded pieces may also feed better, so it worth trying to heat the bottles to shrink before shredding.

[@bl4xxun]

You could grind your pellets to get them to the same density instead of pelletizing your regrinds and put them through another round of heating up

[@NicksStuff]

Could you send a handful of samples to CNC kitchen and have him test the mechanical properties of recycled filament?

[@bluebens2761]

I would cut two holes in your material dryer/oven, one on each side then put a blower on one side with a hose running from blower to one of the holes you cut then on the other side of the dryer connect another hose and run it to a box connected to the bottom of the container you have your material in after you have cut off the bottom and replaced it with a screen. Then you will be blowing hot air through the material which will obtain proper drying rather than the moisture being trapped in the container/material.

[@AndrewHelgeCox]

Could you press and heat stacks of PET bottles into 5mm thick sheets before grinding so that they grind to chunks rather than flakes? Could be tried with a panini toaster and two sheetd of baking parchment.

[@inventtory1272]

Has anyone at your Makerspace ever tried printing regrind with a pellet extruder? I'm genuinely surprised I haven't seen this tried. I would imagine it would be difficult, like anything else, but one would think that it would be worth it to skip a few steps. Even if the amount of regrind to fresh pellet was low, I would think it would be usefull.

[@DrDFlo]

Yes, I have! You have to print slower due to the lower bulk density of the regrind. But definitely possible

[@inventtory1272]

Honestly, if I ruled the world, I would simply design an extremely rugged pellet extruder designed specifically for regrind. Even if the prints were low quality it would be insanely worth it to completely remove the idea of filament from the system. I can't help but daydream that something like this would open up the door for the grinding up of household products for printing. Sadly I have limited resources for such experiments.

[@inventtory1272]

@@DrDFlo Oh excellent. Sorry, I missed your answer while typing that other comment. Simply knowing that it's possible is a massive help towards me trying it for myself in the future. Thank you very much.

[@C-M-E]

I mostly specialize in material development that can be more easily transferred into alternative production methods and am currently working on a solvent-based extrusion method for ABS (also easily adaptable to other plastic/polymers in the recycling sphere of interest that work with easily obtainable solvents). It's a real easy build that can be done in a weekend, as I just obtained all the remaining parts to mock up the extruder yesterday. If you're interested in yet another project, this will definitely cut down on redundant processing of oddly-shaped flake, but better yet, should be able to bypass the shredding phase altogether. I do have a high RPM alternative shredder that kicks out almost powderized stock, but have been loading simple compressed samples quite well in my testing phase. I'm currently focusing on recapturing the solvent for subsequent passes as that is the part I'd most like to reuse, as it contains quite a lot of liquefied microplastic stock. Not that it's terribly expensive, but being able to reuse the solvents makes it that much more affordable rather than letting them vape off to atmosphere, aside from environmental concerns with doing so.

[@DrDFlo]

Always interested in alternative methods of recycling! ♻️ Please consider posting your build to my forum: forum.drdflo.com/

[@C-M-E]

@@DrDFlo Will do! I hadn't documented much during the build as it was a personal project at the time just to test a material, but it turned out to be so cheap that it could solve a lot of problems. I'll work on a write-up as the build progresses. Just got the extrusion body done this evening, on to testing tomorrow!

[@FALLAXT]

What an outstanding video! Do you think you could improve the extrusion of PET by grinding it to a powder instead of shredding it or will the same problem occur as with the PLA particles that are too small?

[@Raishikaku]

I know this is an older video but kinda curious, a couple of things did you dry the materials before trying to extrude them and also had you considered melting the recycling materials into sheets or something rather then just schreding the materials directly? Just a random idea i had.

[@georgstreitz6003]

A really informative Video 👍 For me it would be very interessting to see if the addition of a little bit of chain extender as masterbatch into the regrind/virgin would further enhance the mechanical properties. Do you have rheometry equipment to get a feeling for the degradation?

[@stevelyons2744]

Going down memory lane a bit. When bottles were glass, and some modern plastic containers, had deposits on them. Returned to a store, if your state participated, you got cash or credit. It was better than shattered glass on the roads and such. Shipping would be hell, but recycling drops in brick and mortar filament vendors could do the trick... a little. 6 kilos of old prints for 1.5 kilo spools. Dunno. Some big box stores do it with batteries. No money, but a central drop off.

[@nikethunner2732]

Thank you for the effort, this was extremely informative.

[@thomashawaii]

Hi, Dr. D-Flo. I have been interested in filament recycling since I began to print several years ago. Now I understand it is not possible to recycle PLA indefinitely due to the degrading problems. But to PET, I have a couple of ideas I think might work but I don't have the resources to try. 1. Like the idea to produce optical fiber, melting a large amount of PET in a melting chamber or through several melting chambers with different temperature settings from softing to melting. Each Chamber has blender inside to mix the material. Then, either use gravity or pressing the melted PET through a nozzle on the bottom to achieve certain diameters filament. 2. Or, melt a large amount of the PET firstly and then cool it down into a big cylinder-shaped block. After that put the block on a lathe and use certain shaped cutter, for example a U shaped cutter, to mechanically cut down a long thread of filament. Either way will save the hassle due to the granulating the pet material. Of course, large scale of recycling PET has already been a huge industry. These two methods I think could be possible for individuals to practice. What do you think? I used to think PLA printing will be the future but now I feel like I am producing a lot of waste from failed print to the skirt. And all the items I print today will eventually become some land fill one day. And the worst part is there is no way to truly recycle it but only dilute with new material. The only way I can think of complete "decomposing" PLA is to burn them in a furnace of some power plant. Besides, I think even if the government taxes PLA to encourage recycling, those online platform like Temu or AliExpress will be flooded with untaxed and cheap imported PLA from China. I kind of feel bad to print anything non-functional now.

[@DrDFlo]

You have great ideas! I was leaning towards using our melt flow indexer (a melt chamber similar to what you described) to turn the PET flake into the initial fiber that would be pelletized before a final extrusion. Besides mechanical recycling, there has been some promising advancement in molecular recycling. Eastman is building a facility to molecularly recycle PET near me: resource-recycling.com/plastics/2023/08/01/eastman-provides-updates-on-massive-pet-recycling-plant/

[@thomashawaii]

@@DrDFlo That is great news. Thank you for your reply. Hopefully there will be a good method to help hobbyists to recycle one day.

[@alexandresibony1345]

Thank you very much for sharing so much. A bit disappointed by all the limitations, especially taking into account maintenance & electricity

[@Ne0kil]

One thing that I was wondering is why are we even feeding the pellets directly into the screw? wouldn't it make the process much easier if there was a some kind of "heated kettle" that would already heat up the plastic and from there it would already be flowing and the screw could press it through the extruder with far less issues. Or am I forgetting something?

[@user-dr2pg8fk2i]

Diameter of tubular plastic should be control and refined by pull and slump rate as it is pulled through a water bath.

[@nietofarias]

@DrDFlo do you know a way to merge recycled PET with something that could transform it to PET-G? Maybe painting the bottle with some chemicals before shredding or pulltruding it?

[@stremstremnik8246]

Отличная работа ! А ты не думал поставить после сопла в 3мм машинку для подачи пластика с замером толщины которая сама рассчитает скорость подачи при уменьшении толщины и сразу нагретое сопло в 1,7 на котором будет уже меньше скачков толщины. И еще не думал экструдер который выдавливает нить поставить вертикально может под действием притяжения будет ровнее толщина.

[@gladiatormechs5574]

where is the place place to buy these PLA PELLETTS.... color gray is preferred..

[@seanwelding4183]

I wish these machines weren't so prohibitably expensive, the setup is quite nice overall. I would love to see more recycling done on a small scale by individuals such as those of us in the maker community, but at $12000 for just two of the four machines you realistically need to make quality filament, the ROI isn't there except for larger businesses that have employee time to burn between other tasks. At $2,000-$3,000 all in for a setup such as this, I could see it becoming rather commonly used, as the ROI on that is more tangible for an avid maker or small makerspace to digest investing in.

[@NicksStuff]

I wonder what is expensive, though. You find new (but discounted) 1 hp motors for $200. Wouldn't a hacker space be able to machine the screw?

[@jeromefeig4209]

I agree with seanwelding4183. I also want to add that the cost that is represented is way understated in that the source of power (electricity) has not been considered nor the cost of maintenance and repairs to the equipment. You have already stated as well that the cost of labor and facility overhead (raw material cleaning, operational, maintenance, and supervisory) has not been included.

[@meansq]

you can orient the screw vertical to have gravity help with those flakes.

[@markumoeder]

This is actually a very good investment if you are operating a big 3d print farm business. But only if you got the experience have source's of free plastics and the time.

[@william-Bartee]

If you make plastic slabs on a press (like brothers make KZbin streamers ) it does not matter all these things ,also a panini press with teflon sheets is what is used with bottle caps to make slabs I later make into knife handles has been fun and I get marble looking plastic

[@elementzero_0]

all this is done at a makerspace? thats really cool!! there are none by me and i want to go to one. where is this one?

[@NicksStuff]

How had is it to add some glycol to your PET? Is it like off-the-scale chemistry?

[@FullSpectrumDev]

My biggest question here is why not have the shredder and granulator "in line" with eachother? Limitations due to power supply? The whole reclaimer setup looks like it could do with significant engineering optimization.

[@william-Bartee]

Would it lower the chance of clogging if machine ran vertically in some way like some have adapted theirs to do