Can you print (with) your spools? 

You should try out regular household plastic waste. PET printing (from bottles) has been explored before, but it could be further refined and there are other kinds of plastics out there as well.

Great Video. Alot of people think it's so easy to just recycle your filaments. Thanks for fully explaining how hard it really is.

I recently read a paper "Mechanical properties of ternary blends of ABS, HIPS and PETG". It's from research in South Africa where there is a substantial purge volume from sheet extrusion when they change material, and they really would like to use the intermediate materials somehow and not let them go to waste. What i learned is that ABS and PETG are compatible with each other and produce a cohesive plastic. But how does it print? It could have really interesting properties, don't you think? And also that adding any amount of HIPS destroys cohesion. Which is funny since HIPS is not a copolymer but a blend itself. One should be really careful with what garbage polymer ends up in the mix, for example any amount of PP would be very much not OK. The other thing i learned is that one can use SBS (Styroflex 2g66) as a universal cohesion agent which may make bad polymers and dumb mixtures workable.

Most of mine are cardboard these days

I love the lizard doggo in the background! I have been so hooked on Satisfactory that I didn't even bat an eye when I noticed it but then towards the end of the video it hit me - Thomas loves Satisfactory too!

Couple years back, I had the delight to work with 3devo products, the shredder and what was then their top of the line extruder. The shredder kept jamming, and when asked about it, their support had no idea how it actually worked, and (I am NOT kidding about this), they took pictures of themselves shoving plastic bits into it with thick wooden boards, and suggested we try the same. Their extruder promised something like 0,5/1kg of filament an hour, but it barely managed to do about 2-3kg a day, that is when it worked at all. An utterly miserable experience, and all those terrible memories of endless lost time came to me when Thomas mentioned 3devo. ...now to watch the rest of the video! :D

What I want to use recycled filament for, on the Prusa XL: use recycled material with a 0.8/1.0/1.2mm nozzle, and make the inside of every model and all infill out of any color. Tool change for the outer layers to be new material through 0.4mm nozzles. How much print time and filament would it save? Can it get close to regular surface quality? Can you ignore more contaminants with huge nozzles?

17K €, certainly not for the hobbyist.

You don't have to make filament with the shredded material. Teaching Tech used shredded prints to make sheets of abstract colored plastic that can be used in DIY craft projects. I would imagine you would have less issues with slightly contaminated shreds. In my opinion, that's probably a much better use for empty spools and leftover/failed prints.

I worked a bit with injection molding during the summer, and yeah... we had 3 different purging compounds to satisfy the temperature ranges of all the different plastics we ran (prototyping machine). It sure is important!

Please shred PET bottles. Pulltrusion recycling already exists, but only uses the middle part of the bottle. I love my pulltrusion recycler, but i always feel bad about throwing the top and bottom parts away

Thomas, it's great to see that even a veteran like you is still learning the hard way! I remember watching you build a Printrbot about 10 years ago, which inspired me to buy my own and get into 3D printing. The printer had its technical challenges, much like what you're facing now. Do you think in another 10 years we'll have a disruptive brand similar to Bambu Lab making 3D recycling as simple as tossing in plastic and getting filament out? We're not there yet, but who would’ve thought 3D printing would be this easy today? Just an interesting thought. Keep doing what you do!

Can you do a material mix of something flexible and something rigid?

Toss up some 80-20 mix of PETG+PLA, to create a weak support filament that prints but then easily crumbles away when it's done with its job.

Do retro reflective like Reflect-O-Lay, but with translucent PETG and translucent TPU

Tom, this was fascinating. Recycling 3D printing waste (and their spools!) is a much more challenging task than most people think and your experience shows how complex getting quality, useable filament can be. It was interesting seeing the whole process with the 3devo products. Also, I just love how you had a handy engine hoist to lift the grinder!

It's kinda cute how excited you were about the mechanically coded safety switches. I work with them so much, I never gave them a second thought.

This reminds me a lot of CNCKitchen's video about the recycling of old 3D-printed parts using a self-built reextrusion line.

I find extruding your own often produces out-of-spec filament, which is generally unusable if it is less than 1.5mm or more than 2mm. I find Bambulabs x1c cannot feed filament out of this range, does Peopoly or Prusa XL have a better tolerance? Can you add the InFiDEL to one of those open source printers to show how well it improves the print quality when using such spools?

There are devices that can identify the type of plastic a thing is using spectroscopy but I'm not sure how accurate they are with identifying co-polymers and such. This might help with sorting stuff before it gets shredded. Also, the contaminated shredded plastic isn't necessarily a lost cause. It can still be melted and molded into other things. The Brothers Make channel has some good ideas on ways to recycle plastics.

LIZZARDDOGGOOOOOOO!!!!! 🙂 I bougth the build gun electronics and plan to print the build gun.

What about PET bottles shredded up and mixed with PETG filament?

what a genius idea, i always hated the waste generated by spools

Personally I want to start a filament recycling centre. But I need funding. Love the 3devo machines. CNC kitchen has one also. I go through about 30 spools a year at present. Much is support material and rafts. Would love to turn that back into filament.

i just saw the lizzard doggo in the background. good to know that you like satisfactory

I've found the prospect of being able to recycle or create my own filament so attractive and appealing since I started 3D printing like 10 years ago. It's a shame that it's still a big hassle and expensive for fairly inconsistent results. The PET pullstrusion technique seems to be the most practical way for normal people to recycle.

Years ago, when I worked at a plastics molding company, they would recycle 'waste' plastics. Sprues, purges etc. They would never use it without adding virgin pellets to the mix. In fact I think it was less than 10% of recycle to virgin material. This was blended in the mixing department. As you found out, keeping the different types of plastic apart was key!

Try to make blends of filaments e.g. PC-ABS. Obviously need to overlap temperatures a bit but would be interesting to see what's possible

Nice lizard doggo. I like it.

Way back in the day we bought protocycler serial number 8 from Kickstarter and actually made about 20kg of petg abs and asa with it. Dry time is about 80C for 4 hours and no food dehydrator is gonna do that better a convection oven. You found out the hard way that is the second biggest factor behind mixed plastic types. Petg is almost infinitely recyclable where abs gets brittle a few cycles in due to butadiene and chain breaks.

We have a 3Devo extruder and shredder. We like it so much, because we can make a lots of different blends and filled filaments. Only downside is the srew. It is not the best at homogenous extrudes.

2:59 Nice Pulp Fiction reference :D

Try to recycle PET from bottles! I’m really curious how that would work

7:40 The term "copolymer" doesn't refer to how well polymers mix, a copolymer is a polymer consisting of several covalently bonded monomers

Can you try some household materials, like shredded yoghurt cups or so? Just to see, if there is a point in recycling this kind of waste by yourself... Or maybe housings of broken appliances or devices like radios tv remotes etc. isn't there the possibility to identify the material with infrared light or so? I vaguely remember seeing something like that...

When you truly think it all through, with the exception of perhaps PET, I seriously doubt that it is truly possible to reuse filament AS-IS. The evidence behind this is that the polymer “cooks” if left at temp for any period of time, which means that it cooks (degrades) to some degree no matter how long it is at temperature. The recycled filament needs something to either reverse the degredation during its first use and the additional degradation that you are going to put it through, or something that can reduce/dilute that degradation. By adding virgin material, you are effectively doing the latter. The exception with PET is crystallization. Once it crystalizes, it is done, unless you do something to reverse the creation of crystals and turn it back into a polymer. Anywho, I don’t know if you are following the law suits here in the US, but the oil/plastics industry is being sued by several states for making false claims in regard to the recyclability of plastics. With over 50 years of data, they have basically proven that recycling plastics is nothing more than a pipe dream. BEST

One thing that I learned working for a company that prints with pellets is absolutely NEVER re-mix material. Treat the material that came out of the machine as “purge” or waste material. There could be metal contamination, other plastics, purge material, dust or other material like hair or wood shaving etc. And Glass filled materials are superior cleaning resins over HDPE. Use GF ABS as a high temp purge material, and GF pla as a mid range purge, and HDPE as a low range purge and make sure it’s milky when it extrudes. If it’s molten and clear it doesn’t grab the waste bits left in the extruder

In commercial recycling they will mix like materials together, but the systems are quite a bit different. The sprue size is WAY bigger than our tiny hot ends. This allows for inconsistencies. Place by me makes plastic pallets and plastic barrel carriers out of recycled resins. The machine is sloppy as all get out, not precision at all. The feed sprue is at least 10mm in diamater...yea, they are huge. You are 100% that when you see "recycled content" it is generally scraps from their own manufacturing. Funny thing there? SO many places where I live have been doing this for a LONG time, but now they are putting in their specifications...AND CHARGING for it. Genius on them, but when I used to negotiate with these shoot and ship houses they were all "Oh this is so complex". I was always "So, please, take me through it, 2 years ago, before your "Recycled Content" resins you had a grinder, drier and dust separator on all your injection mold presses. You took the sprue(s) and runners and put them into the shredder, it then went to the dryer, then to the dust separator. There it was metered into the resin. What changed". Of course...NOTHING. Except they charged MORE because "it requires more process". Yea...and so many people ate that up as fact. :(

i work at a company that makes large scale extruders and filters for plastics recycling. it really is super important to have good starting material. Even when recycling, if you put garbage in, you will get garbage out. thats especially why plastic bottles are nice to recycle. you know what it is, so you can seperate the different plastics from the lid, lid liner and bottle using a sink-swim seperation, or even camera, or laser guided seperation. it just gives you a nicer starting point. when just recycling from the plastic bin, you just cant get it up to the same quality results. I remember a test we ran a few weeks back that used mainly candy wrappers and yoghurt lids as a starting material. Almost all of it had aluminium gassed onto it on one side. even when filtering that pretty fine, you will get a material that you cant extrude well enough to feed it into a mill to granulate. It will pass the extruder just fine, but the small remaining contamination will change the material properties, making it brittle. And filtering it with finer sieves would require too much pressure for the sieves to hold up. so, sometimes you just need to add virgin material, or wont be able to recycle stuff. this is also why it kinda sucks if you have parts made from a bunch of different materials. if your one plastic part uses 5 different kinds of plastic, or if your Tshirt is half cotton half plastic... it just gets harder and harder to recycle. luckily if the starting material is ruff, our extruders de-gas using a vacuum system, so its always dry and free of oils and glue, but it clogs the filter sieves so you need to change them more frequently. worst case it may cause the line to shut down from pressure build up, if the contaminates are way too much for the system to take. oh also, we always flush using PP. You really only need to disassemble a whole extruder once to always remember to flush ;D

One experiment i'd be interested in is how much performance of pla degrades as it is re-recycled. How is the plastic affected by several runs of extruding, printing, shredding and extruding again. How many cycles does it take for it to be not usable anymore.

Even in normal production environment, we are also using some virgin material together with shraded one. It gives more cosistent injection moulding and less chance for defects

All very interesting I enjoyed the video. As somebody else mentioned though, I'm starting to see more cardboard spools. One problem with those on my Prusa MK4S, is the spool holder is on top of the printer above the bed. And as the cardboard spool turns on the peg of the spool holder, it snows cardboard dust just a little down on the bed. So I made some PLA spool inserts that I press into the spools when I get them to eliminate that problem.

I know the owner of a plastics factory. They recycle their waste in some products where color isn't important. Sure they shred and add to virgin pellets not extruding it. But he told me the recycled plastic is degraded and they only use it at around 25% recycled and 75% virgin pellets to ensure a good end product. He also said 50/50 would likely be fine but they don't produce that much waste. Maybe if those ABS spools were mixed with new pellets it would work ok. It would be great if you get a chance to try that. Cheers!

I've seen this machine it's a beauty

Are you able to try some other additives, say carbon fibre or glass filled filaments?

PET bottles ofc!!! :D these take the most amount of space in a regular household.

Would it be possible to make a custom glow in the dark filament? Fluorescent pigment might be too fine for this machine, but I am curious if its possible somehow. Could probably make a really interesting colors!

What I don't get is why everyone hasn't just adopted a similar refill system to Bambulab spools. Reuse is the best part of the 3 rs

I wonder if used PE bottles (milk, though they maybe have different material as a liner inside?), laundry detergent or other cleaning supplies bottles would print well?

trash printing all kinds of containers and lids would be a nice thing, or graphene infused material nice editing and filming, and now you have a setup straight out of everyones early 3d printing dreams

The first thing that popped to my mind when your first ABS batch went wrong was "Don't they usually add virgin material into the mix to lessen the polymer degradation?". And the answer is yes, usually the mix is 70% recycled and 30% virgin to make pretty much mechanically and chemically identical polymer as it would be 100% virgin material. The polymer degradation is quite fast thing, like everyone with some old cars knows the trick to give sunburn black plastic parts some torch or heatgun to turn them back to true black but you can do it only once and even after it the parts will be a lot weaker, that's polymer degradation and one heat cycle is already quite big thing. You can make 100% recycled plastic but then you need to chemically treat the material for that polymer degradation. Also the clean is the word. Probably many have and will comment about PET bottles and you really need to clean them well, like there must be nothing in them especially sugar (or sweeteners in general, they're all sugars but some are more sweet than others so you need less of them).

How much filament would you need to extrude to offset the cost of recycling machine?

I - love that safety feature. I cannot afford these machines, but If I could - I would consider that a huge bonus when comparing machines. To help test spools you can also use some basic chemicals to see if they melt or discolor, ABS as we all know will melt down with Acetone, so a few drops on one - and see if it begins to melt. If so - probably ABS spool. Others have other chemicals, but starting with ABS (probably one of the most common) helps eliminate the need for riskier chemicals or methods.

Best thing I can think of is grinding them down and then instead of an extrusion process, use a compression process like you're pressing the material into something like a brick or some other kind of simple/useful shape.

I'd like to see if there's a way to recreate PLA+/Pro blends. Most of them are a secrete blend of additives that make them stronger than regular PLA, and it'd be neat if you could try making something comparable to something like Polymaker's PLA Pro (I mention them specifically, since they have a standardized testing method they use for their filaments). It'd also be fun and interesting to learn what additives are possibly being added to make them strong.

Pearl pigment for car paint/plasti dip could look cool. It's what they use to make cars that seem to change color based on the light direction.

Tom, it'd be cool to see you make carbon or glass fiber reinforced abs. I've seen these powders or chopped fibers available to purchase for a pretty low cost but i am not aware of a good way to mix them consistently in the hopper.

@11:57 that's the same color that our shoes would end up colored as when working in automotive paint booths. I suppose it raised some eyebrows out in the public. We also did ABS regrind onsite at Saturn (Saturns had the plastic panels of course). IIRC, the mix of old to new (virgin) was 10% old, 90% virgin plastic. Our silos were ~27.5 meters tall though... :)

For your contaminated PLA material you can try using The density of the material as a separation method, or you can use some sort of solvent to melt out the ABS

I think the really interesting part of extruding your own filament is the potential for creating custom blends. I wonder how you would get on with your virgin abs with some added chopped carbon fibre or glass fibre?

I just use my old spools to hold custom multi color filaments and sometimes to transfer filament to from messed up cardboard ones.

For drying your ground plastic you might want to integrate some sort of agitator or stirrer into your drying setup

the best solution are cardboard rolls or perfect would be if 3D printing will evolve into directly printing from small pellets that are packaged in a lightweight bag. But as previous projects have shown, printing directly from pellets comes with a ton of new compromises.

I'd love to see someone try making wood filament from this process. Odd wood species like padauk, purple heart, ebony etc.. would be fun to see.

Hey I have a few kg of polystyrene spools I shredded about a year ago just in a bag. I was waiting for this video.

Perhaps you could try making your own wood, glitter or even metal filament? By metal I mean the types that have some amount of metal (dust/flakes?) mixed in for a metallic look.

We own a 3devo Precision extruder and a small shredder by QiTech (built like a tank!). The recycling process is fiddly, but it's actually possible to recycle PLA and to print with no issues with produced rPLA. Our experiments with HDPE filament production (our actual goal) were not successful though.

Now that you’ve played with the 3devo, I’d love to hear your insights after another inspection of industrial grade compounders! As you pointed out, it’s tough to get a good mix with shredded plastic in such a small extrusion system like the one in the video. Reach out to me if you need access to a research compounder!

Abs is almost the same density of water and PLA is heavier. Maybe you could separate them by throwing into salt walter and removing everything that floats

They sell you a huge grinder that generates microplastics when all they needed to do was have a pre-heat chamber to make your source material able to blend together. The auger that feeds the extrusion can be preceded by a mixing system using arms or motion, etc...but grinding doesn't need to happen, I guess they'd have to include a precision controller and more sensors but it would take up far less space, make far less impact on environment, be much less expensive, and a huge piece of equipment made by consuming and/or contaminating a lot of natural resources completely avoided. The extrusion is working okay, though. That in itself is pretty impressive! But careful - if you turn all your spools into filament, you'll have to print a spool to keep it on.

It might be possible to separate the contamination out using a saltwater bath. (Dial in the salt concentration to a point where one material floats and the other sinks)

Great video about recycling the spools using the 3Devo machines! You got some nice filaments out of it. I'm just wondering how glow-in-the-dark filament mixed with normal filament would do?

Step 1) have an expensive machine Step 2) have an engine hoist Step 3) ???? Step 4) profit

How much calibration did you do for each filament before doing the printing tests? A lot of the drawbacks you saw in the printed samples can be caused by sub-optimal print settings.

I think using the shredded material to do injection moulding would work much better.

I would like to see a material property (strength, flexibility etc) comparison of recycled material vs virgin off the shelf material.

I try to buy refill / spool-less filament. I then print the spools I need and reuse them as often as possible. (3D printed spools do break down after a lot of uses)

I don't have a filament extruder, but I still shred my failed prints. The failed prints are used as ballast for situations where I need the weight but not the strength. (think paperweights and stands)

It seems like this would be ideal for 3-D print farms that use a single material and perhaps a single brand of that material for all prints. Probably still a good idea to mix it with some virgin material.

I accidentally bought some recycled fillament tried printing and it was garbage, all bendy and not stiff. I wish it would work better.

How many times can you send the same plastic through the print>grind>spool>print loop before it becomes too degraded from heat or other reasons to be useful?

It'd be interesting to see the good recycled ABS spool be printed into Voron parts.

try doing some experiments adding fibers, dies and other non usual materials that can be added to the fillaments, either to make then stronger or with different color and properties!

I would like to see you play a bit more with Ps spools, maybe add some cirgin PS or HIPS material in the mix. PS spools are the most common ones so it would be interesting to see.

Spools ought to be made with re-inforced cardboard, and a removable plastic ring insert so ragged edges and rough surfaces don't hold anything up. At least if the cardboard is binned it'll decompose or cook nicely.

Thomas, please tell us why you have an engine hoist. I am intrigued .

Remember the grocery store bed adhesives video? I think I have an idea for part 2 I want cheese filament!

Silly question: how much using a 0.8 nozzle changes the game regarding usability of recycled filament? Is it just as easy to klog ?

At 3:14 there are two things being done wrong: 1. Ratchet straps according to EN 12195-2 are not to be used for lifting. Better thing to use would be something like round slings. I'm aware not everyone has them laying around, but if you own an engine hoist, you should probably get some proper lifting gear. 2. You should not be putting these hooks into each other. It will cause the hooks to widen and form hairline cracs, which can lead them to break far below their load capacity.

PP is the most difficult to print material I have ever tried. It warps so badly that it pulls the PP tape used to make it stick. I'd be curious to try some PP blends that would retain its bending properties and reduce the warp (or make it stick to PEI). One thing I'd try would be to add some virgin ABS to it (hopefully without causing the issues you faced). Another idea would be to try creating a flexible blend.

Why not trying to shred abs car part (the bumper parts with no paint) and try to make 3d printing filament?

sure you can! :) just need to chop it, melt it, and stretch it ;) recycling is cool

Could you use the difference in density of PLA and ABS to separate the ABS from the PLA. Perhaps using a salt water solution with a density of about 1.1g/cc so that the ABS will float and the PLA will sink?

It would be interesting to compare prints from recycled PET bottles using this 3devo system, compared to the “pultrusion” technique used by the Recreator.

You should shred an old 3d printer itself. Then reprint it 😬.

HDPE was used as a purge material, but I wonder how it could work as a printed material? (Or a blend with HDPE?) it’s very common as a household plastic. I think it would work well as a material for containers or working pets like gears or cams.

How about HDPE plastic? It's very common but has a lot of shrinkage. I don't think I've seen anyone print with that, you could give it a go maybe? Great video. Keep up the good work.

MMH did you wash the plastic before or after shredding ?

Ive always wondered about the difference between "soft pla" and "hard TPU". The hardest TPU I can find is 64D or so, but I never really tried soft PLA. I am curiouys though how they compare.

Thomas, sorry that I couldn't contact you any other way, but I need to ask your opinion. As a respected member of the 3D print community, I was hoping you could lend your expert opinion to my question regarding a swappable nozzle system for the Bambu P1S. I only have the standard nozzles now and was wondering what you would suggest as being a good product to use. I am considering doing a lot more with the printer, which may involve swapping nozzles more often, and I would like an easier way of doing it other than with the default “complete” hotend units on the Bambu Lab P1S. Remove 3 wires, remove two screws, remove complete hotend, and reverse to install. I know it doesn’t sound like much, but if I could simply swap the nozzle, I think it would be less time consuming and fiddly, especially when dealing with re-attaching the wires, which I have found to be very persnickety. Thanks for getting back to me!