PET Bottle Recycling: Waste to 3D Printing Filament

Let’s learn about annealed PET!

Im still wondering if you could join 2 bottle into 1 continuous filament

Nice I just don’t have the money to make the kit :(

If this let you join bottles and keep making to 1000g of filament I'd be in, so far this is just neat though.

Yep, waste of time really. Think about all the tools and EMERGY you use just to be able to re-use a bottle that is likely more efficiently recycled by your local recycling company.

hello and thank you for your videos at my work he throws away hundreds of bottles per week and I would like to recover them to make filaments I have a question where did you find the stl

I admire the concept, but I don't think the time making your own filament is justified.
I'd prefer to just exchange the bottles for their deposit and use the money to buy filament that's readily available. The time could be much better utilised on other projects.

In Croatia, the return fee for PET bottles is 7 cents (0,07 euro).

Let's talk economics. Let's say it's 50watts for the nozzle... It took about 2 hours to make 30 grams of petg. That's about 66.6 hours for 1kg. Which is 66.6x50/1000 = 3.33kwh. Times whatever you pay per kwh, 0.39 euros in my case = 1.3 euros for 1kg...not bad 🤔

But we have a 25 cents per bottle return program as well. So stephan got a 30 yield out of 1 bottle, its a 5 liter bottle let's assume for simplicity sake that I use the exact same bottle as well.
30 grams out of 1 bottle... That's 33.3 bottles per kg. Which is about 8.3 euros in "missed" recycled program money. 8.3 euros for 1kg of filament is a good deal.

But, going through the hassle of collecting 30+ bottles, cleaning them and prep them is far from economical on this scale.

There should be a way to recycle failed/unused 3D prints. Maybe a collection service in the bigger cities?... I think that will have a bigger impact on plastic waste then collection bottles (especially in countries with a good collection program).

Legit have been waiting on this lol, I saved all the components of my old E3 for this exact reason. Thanks Stefan!

With the PET being rounded into a tube, could you also fit another filament into it? something like a PET wrapped Carbon fiber filament if it got hot enough to blend it?

One pet bottle is worth 0.25 euro cent .
In order to make enough pet filament .
You will need more than 160 bottles .
Bringing the bottles back to the store gives me 40 euro .
And with 40 euro I can buy 2 kilo pet filament .
So nope your idear fails in my country .

hi Stephen can you put a diagram off the motherboard so I no where to put the wires from the ender 3 all the best Richard

I do like the idea, but I‘m not sure with the energy used to clean your containers, smooth out their form, extrude them, plus the used solvent, that it’s really that much more ecological than bought filament. Maybe it is if you’re working 100% off your own solar energy.

When using the filament roll powered by a stepper to pull the plastic through the hotend, you are likely to stretch it as you get more layers on the reel.
I have seen some where they have sensors to adjust the pull rate with the tolerances set ~.05mm.
Still a good idea, especially recycling old/broken/unused printers as well as bottles.

thank you for that video, It would be nice if there were an extruder that could process flat PET material, along with a heat block that could do the same, so that one wouldn't have to prepare the material so elaborately

Heating the bottle to remove the label, heating the bottle more to remove the ridges, using solvent to remove glue and printing on the outside, and then heating a hotend for over 2 hours … all to get less than half of the PET back as filament (of which you need 30% more when printing with it)? Sorry, but this just doesn't seem like a good use of energy and resources.

Could you test the aurapol pla ht110 filament? A comparison with other high temp filaments would be nice

Great video Stefan. It doesn't look worth the effort, TBH - I suspect print failure rate could be above average and the slow printing (4mm^3per sec !!!) will definitely be a negative.
But I love that you do these things.

Best to your daughter - you must be a proud father...

A Trash-er hunt maybe?

R.I.P. ender 3

You put so much time and energy in recycling this, just buy the filament. Use the savedtime to clean up nature.

Alle Flaschen über 3L haben keinen Pfand und kosten meistens sehr wenig mit Getränk.

I don't know about this, you need to pull at least 50-100 bottles to 'break even' on plastic and emissions and it seems like a ton of work. Personally I don't have any such bottles either.

A diy method of recycling scraps would be far more interesting.

Can you join the filament from each bottle together?

I'm bit interested in this but the main concerns with this is the dangerous fumes this may produce while "softening" up the strips of PET bottle. Would we need to set up a very specific container around this with fans around it running to outside? or would it need to be filtered through a filter with fans? etc...

and the hollow core within those PET bottles/filaments, would they close together more better if there's a certain part between the heater and the bottle strip cutter to force it into rolling up before heater block?

Stefan,
Do you know if anyone has used a small injection molding machine to preprocess the platics into "glue stick" sized cylinder in the format of 20-50g samples, and then using pulltrusion to a smaller diameter?

I think You did something similar with 2-core material samples (PC + ABS); but I think that the feedstock of the injection molded is promising for re-using the threaded heads of the bottles; as well as pre-filtering through a screen, and resetting the plastics memory.

Mixing the shredded plastic as regrind would make the melt more homogenous by an average of all of the varying materials; which would need less adjustment on the machine end.

Using 2 or the successively larger machine molds could get several layers to the material cores for strength, or for colors.

Used to work in injection molding for nearly a decade. Curious if you have considered this, or heard of anything similar.

it seems be a good idea, but imploration, far from ideal, it only using 30% of what is almost 100%, the same stuff?, good 30% of essence your trash bin! 🙂,
do wonder, why, it just not melted after all that's what plastic does best, build based something slow cooker, with hole leak, and catch dripped leak let cool, like you machine is doing here, spool it up are what ever, at just run that thru machine in sted the a bottle being uncoiled with the cutter?

Do bottle to filament to bottle again

Could you possibly cut the filament into pellets for use in blow or injection mold?

So how did you get the opaque material?

I still use and love my ender 3 😭

It's an entertaining waste of time... called a Hobby.

Some hobbies are learning opportunities that can eventually lead to careers and occasionally a revolutionary idea.

I am not sure I would call that "easy".

I really don't want to down vote

I've been watching this PET bottles to filament projects from at least 2 years. With all the respect to your hard work Stefan, in my opinion this has nothing to do with ecology. Yeah, great words about saving the planet, clean up the environment, recycling materials etc. Dirty bottles are unusable as long as you don't want to spend clean water we suppose to save (how many litres per single bottle?). Detergents, acetone to remove labels and then dirty paper towels (harmful to environment). Reshaping empty bottle using 600-1200W heatgun (around 50% of electricity in Germany is produced from fossil fuels). 2 hours of "printing" to get 31g of material out of 80g (low efficiency, low productivity, electricity). Pure PET is hard to print, require higher than PETG temperature and slower print time (again wasted electricity compared to other materials). Now the most important part for me. What should I do with this short pieces of filament? I've never seen a single "bottles to filament" project making even 100g of filament in one piece. If we keep using electricity, acetone, cleaning materials and our precious time to keep printing 3D benchys, were not helping our environment. We are working against it. I'm sorry for being honest.

I started using PET filament made at home about 2 years ago. I don't buy filament anymore. I can get 80% yield from a bottle and my filament is not hollow thanks to an special very long nozzle I made.

Hi Stefan. Ich würde mir das gerne bauen. Kann ich das auch ohne einen ender 3 zu kaufen? Gibt's die Teile bei aliexpress oder so?

While your brilliance and DIY engineering excellence really shows here, I think this is such a complete waste of time for a tiny amount of filament produced. And the filament produced will be so incredibly inconsistant. Also the label removing and precleaning itself is extremely time consuming let alone the process of actually getting a couple of feet of filament at best. Unless filament recycling factories start doing this on a large scale, it really is just a project for someone with way too much free time for very little in returns. Heck, even the electricity used to do this costs more than the savings. Recycling isn't always an economically sound practice. Unless it can be done on a large scale, it's not practical for or economical for 3D printing.

We went to france for summer vacation this year and although there might be places in europe where things are worse, unfortunately france doesn't seem to give a flying f*** for the environment! If you find a bottle collecting machine in a supermarket it's down to purely good will of the company. No nationwide recycling of plastic! That's the perfect spot for this machine.

my bottles are worth money so no ...

Can you give me a present? I'm from Korea.

Why not make a hundred of these (for a start) and start a factory in one of those countries where it is a pest? Creating job opportunities, cheap labour (fairly payed but admit it they do not have a high inflation like we have), and cleaning the environment 100 bottles at a time, then selling the filament worldwide, if you make enough profit, you build another 100 of these machines and so on, boom
make them operate on solarpanels or windenergy, Boom green factory
make some fumehoods, boom safer to work with
and so on

I've been looking for a way to recycle my old pets!

is it really worth the hassle if you factor in the water to clean the bottles, the acetone to remove the stickers, the gloves to protect yourself, the energy used for the heatgun, etc.
don't get me wrong, pulltrusion is a really great way to get your hands on filament in some areas of the world (enough solar, water and bottle-pollution present), but in germany?!

now hook it up to a 3d printer and print a bottle, then have that bottle be unwound back into filament

using heatgun and solvent to recycle the bottle seems doing more harm to the environment instead

it still costs money to drive to the recycling center