Recycling waste 3D prints with a Precious Plastics shredder
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- เผยแพร่เมื่อ 11 ส.ค. 2019
- In an effort to recycle waste prints, I had previously used a garden shredder and modified paper shredder together with some success. It could only handle thin pieces, however, so I had been planning a bigger, better shredder for some time. When I found the Precious Plastics bazar, it became feasible to put one of these machines together without too much time commitment.
Driving my shredder box is a 500kg garage winch, partially disassembled. It has more than enough torque for the job. The weak link is the coupling between the two, and although I have it working for now, it’s going to need further improvement.
Performance is outstanding! I can crush pieces I designed to be bulletproof, such as 60% infill, thick perimeter parts for the MPCNC Lowrider 2. You can’t do too many pieces pieces at once but if I shred as I produce waste it will be fast and efficient. The smaller particles melt in my oven in a much faster and more uniform way. I'm planning to mill and laser cut some parts, but ultimately want to make my own filament. If you want your product featured, get in touch.
I know not many will follow this at home but I feel passionate about this project and want to do what I can to document solutions to a significant problem.
Thanks to my generous Patrons for making this project possible
Looking for an alternate solution? Check out the great work of Augustin Flowalistik’s Plastic Smoothie project: www.instructables.com/id/Plas...
Finally, CNC Kitchen made a great video on recycling prints into filament: • Recycle your failed 3D...
Part 1 of my shredding journey: • Recycle waste 3D print...
Precious plastic website: preciousplastic.com/
Shredder instructions: preciousplastic.com/en/videos...
The shredder box I purchased from the bazar: bazar.preciousplastic.com/en/...
Garage winch I used: www.ebay.com.au/itm/392078776463
Rack It modular shelving from Bunnings: www.bunnings.com.au/our-range...
Buy quality and affordable filament from X3D. Buy 3, get 1 free and a free sample pack with every order: www.x3d.com.au
Take a look around and if you like what you see, please subscribe.
Support me on Patreon: / teachingtech
#preciousplastics #shredder #3dprinting
given the torque of that motor it may be worth bolting the metal frame underneath the mdf sheet so that the force is distributed over more area instead of the 5mm or so around each mounting bolt
I was about to type this.
Thanks 🙏
Bolts are not pins and are not design for shear forces so they will always fail. If you need transfer so much torque you need these shafted to be keyed.
3d printing community and good mechanical design are worlds apart, all these years and still misusing Z bearings on every machine on sale
@@lezbriddon how are Z bearings misused? Can you explain?
Hardened steel coupler and mild steel pins is the way to go.
What he should've done is just Thermite weld the shafts together. Those shafts would never come undone again.
Or replace those bolts with dowels(?)
Oh man, you really made me want to build one of those so badly!
Didn't know that the marketplace existed. Maybe I can also grab a kit there. Thanks!
Maybe it's a dumb question, but cant you just use a blender. It would be a lot cheaper and safer. Just wondering???🤔
@@scavenger1776 Too high RPM, too little Torque
i can see your youtube yknow
@@TheNigaHigaFan4Ever Have you never seen "Will it blend" videos? :D
I just realised I accidentally pulled a duck face in the thumbnail :/ Now that I have your attention it's a good chance to thank my patrons for making this project possible and Martin Zeman for posting camera tips that finally got rid of the flickering in my studio shots. I'm always trying to improve my content and constructive feedback is very welcome.
Michael, no worries about the mug shot. 🥴 Your dedication to provide quality content is very evident in every video!
Blue Steel!
@@42jnyl Magnum Michael
Awsum. Tip s ..I gess save s buying one. If built good .recycling pla an plastic s. Of bottal milk lids is great. I first built a 3d printer kit now to get it working. An to created own. Plastic on reals to print. Is cool as. I got sume info in 3d printing book few year back
A couple suggestions for version 2:
1. Use a rigid steel base for the shredder and motor. On the MDF base, there's a lot of twisting between the two exasperating the coupling failure. Align the shafts properly.
2. Add a VFD to control the speed and reverse the shredder when jammed.
3. Using torque/power feedback from the VFD, add some control to automatically reverse the shredder.
4. As suggested in the comments, add an interlocking safety circuit to those "access" panels. Accidents happen and you probably still want all of your fingers.
5. Figure out the maximum torque and get a flexible coupling suited to the task. I might suggest a Falk steel-flex grid coupling. May need to machine those shafts to accept a key or better yet, a splined connection. The shaft key and keyseat will be your weak point. That is where you need to set the torque limiting below. There is a lot of torque from that repurposed winch.
You've inspired me to design a build one myself. I'd be using it for the same purpose, 3D printed plastic recycling. Thanks!
Hi Mike ! I am a retired Tool, Die , Mold Maker. What you really need for a coupling is a GEAR COUPLING! This will never fail you. The people that told you to use that rubber coupling, and then through bolt in shaft “FIX” is not the answer! Also, cut off the 20 mm ends of those shafts, and use the larger shaft diameters that you have Couplings can be ordered with dissimilar diameters if required. This will be a robust change from what you are doing.
* Love your Channel! I also learned a lot!.
Awesome! looking forward to the filament extruder. B-)
I too feel strongly about the waste I'm making with this hobby. I've saved all of my failed prints in hopes that an affordable solution is born for reconstitution. Keep it up!
Dave Hakkens and the precious plastics crew do amazing work.
Great video, and also I'm honored to be recomended in the description. If anyone has any question concerning Plastic Smoothie, let me know!
I tried your blender technique and it worked quite well but I was after something more automated/faster. Thanks for all of your work and great 3d models.
The shredder really looks awesome!
Well this is the easiest part of recycling.
It'll be interesting only when a useable filament is reproduced
I know. I made a giant blender that minces the plastic rather well, but I have yet to succeed in extruding plastic.
It's as if we read each others minds! I did the exact same thing....same style of hoist motor, exact same initial coupling (with similar results) and same solution with a large bolt. If I could attach a photo you would laugh at the similarities. The only difference is I am in Canada so my build came in about 1/2 of yours in cost. I have a Filustruder assembled and ready to try making my own recycled filament. Cheers!
Loved the video! I've worked on industrial size shredder for plastic and there to the couplers where the weak link, they used 4 bolt flanges with a taper pin through the shaft on each side as the sacrificial part. Thanks for the great video 👍
Great video. I was planning on making a plastic shredder for my kitchen plastic waste and this video probably saved me a lot of trial and error. One thing you did not include in your hopper is a safety cutout switch. Any equipment capable of removing a body part, accidently, should have a safety switch that prevents accidental operation unless all openings are closed. Not only is this a legal requirement for machinery but it is good common sense, especially if there are children around. That shredder is definitely an arm eater. Keep up the good work.
While you have a point, common sense and not letting idiots who touch everything into your workshop goes a long way. Show me a single wood worker that has the safety guards on their saws etc. If your child loses a hand in your plastic shredder, maybe you shouldn't have been letting them play with it in the first place, it's not a toy.
Two words to fix your coupling issue. Key way. Either cut one with your cnc or have one cut by a machinist and get a keyed coupling from an industrial supply place.
Great video! Really enjoyed watching how you worked through the problems you were having
For the extruder, I've made some research of accessible filament extruders, and what I've come across is the lyman filament extruders. The dude has built a lot of versions when i last checked. I think the latest version is V6. He has the process all documented (and pretty well documented, at that), for all of his versions of the extruder. It's all on thingiverse IIRC. Thank you for all the entertainment and just overall great tutorials. My ender 3 wouldn't be even close to what it is right now without your videos.
A v6. Yes. I herd it awsum. I luv even a v2// till got $$ for a v6.
I built one 5kg per hour filament extruder, here's the overview: medium.com/endless-filament/make-your-filament-at-home-for-cheap-6c908bb09922
Ayrton senna, you know the things man
Thumbs up for the Senna hoodie!
Very cool to see a fellow precious plastic builder. Awesome idea to use a winch assembly.
Great video, thanks for posting. I am also wanting to follow the recycling path of failed 3D prints and plastic in general. I have purchased a shredder but was waiting for the right motor to become available. Very happy to see your version work so well. Hopefully you can come up with a reliable coupler.
Nice Michael for looking at this, I'm looking forward to you making filament also!
You might want to add a kill switch to the side doors for when you have your hand in that death machine
or just dont be an idiot
@@Enviousttv Accidents don't discriminate by intelligence.
AND always unplug it, for when the kill switch gets bumped or fails ON. Sure it's inconvenient, as are emergency room visits...
The problem with "don't be an idiot" is the texting while driving effect: when we're focused on something else and only a small part of our attention is available, only a small part of our intelligence is available and we do stupid things. With a shredder, it only takes once and you're learning to do without part of your hand.
Depending on how bad it is (fingertip cut vs. it got a good grip on multiple fingers, then stalled).
The don't be an idiot factor should tell a person to UNPLUG, AND DISCHARGE MOTOR CAPS BEFORE DOING ANY WORK. Anyone STUPID enough to not take that precaution is asking for a bad time. Simply unplugging is not always acceptable as some high torque motors have a high discharge starter cap in or on them. This can cause a spontaneous cog in the motor even when unplugged. Short the motor after unplugging any high torque device.
Very necessary. The problem is not so much hands as hair or clothing. Maybe not even yours, just some visitor who is peeking inside.
Great video! Thanks for sharing the results, I built that shredder box and while we know it is a beast it is great to know it stood up so well!
Some of the issues with your coupling setup are related to the length of your output shaft (shorter means less movement) and the timber mounting (steel mountings reduce movement). We use jaw couplings with rubber spider and a keyway (grub screw fittings cant cope) and so far, so good ;)
That Ayrton Senna jacket tho!!!! NICE! the one Brazilian that didn't disappoint our nation!! .... and gr8 content BTW
Precious plastic- Dave Hekkens and the team, great guys!
Haven't finished watching the entire video just yet, but a thumbs up and a comment for the SHEAR effort on this video!
Wow, well done!!!
Thanks for sharing :-)
Nice one man...and by the way, nice jacket...he was great guy!
Here in Brazil, we loved the "Ayrton Senna" Jacket you are dressing.
The reason the coupler is strong enough in the tutorial video is that they've flattened off the hardened steel to face the allen key. The other options are the same as the key broach that your original lift mount used. You've still got the key in there. You could shorten the output shaft of your motor and use the key broach but then you still need something at the other end. Is it broached too? If not you're then down to potentially flattening it off or get an actual adaptor that will be considerably thicker than the 20mm ID pipe you're using. "Rigid shaft coupling" might also help with your google-fu to find something which can spread the load across the shaft if it isn't broached.
Thanks. Learning something new. Now to Google for the meaning of broached
Yeah, coupler is a waste. Easy enough to make your own
You are amazing bro! I was getting a lot of trouble with motors until a saw your video! Thanks and saludos desde argentina!
I worked with the charity Edukid to get them using this to recycle plastic in Cambodia. Fantastic to see it in action. Long term I would love to get a schools iot where kids design the molds for plastic bottle led lights with a 3d printer before injection molding their design and wiring the electronics.
Love joy makes good couplings
I wish you were my neighbor lol, all the fun stuff you come up with.
Child's play.
Go follow diresta.
I laughed at the fact every potential issue just so happened to have a simple solution... That was a good day
I thought of a few comments (touch in cheek) as I was watching this video. However, after sampling a large quantity of your countries wine, I thought that I would say: Boom!!! Good job - loving this video 😀 you did an awesome project 👍 and made an awesome video 👍👍 Thanks buddy 👍👍👍
I just so happened to have made this same setup, same shredder, same motor, different brand name, but it's identical, except my gearbox shaft is 18mm hexagonal.
I welded a socket onto the shredder shaft, then used an 18mm deep socket on the gearbox which I didn't weld on, but let float.
I then used a 1/2 inch drive square to connect the two sockets together. This has enough wiggle to handle the two shafts not being in perfect alignment (they're very close though, may 1/2mm out)
I've managed to stall the motor, which I think is putting out around 300Nm of torque after the gearbox and the sockets are fine.
You need to implement a woodruff key into your coupler setup for ultimate reliability, and largest shear plane.
Thats how industrial applications are setup.
You’re brilliant.
I Love this Senna's shirt!
It's Cool to see the Makers 'own-up' to #Recycling, as it is one of the Other downsides of Commercial Mass Production.
I would love if you'd do a video about the extrusion machine as well since it would be a nice all-in-one kit
I will explore every option I can find. My impression for the Precious Plastics extruder was it wasn't set up for precision like what we need for 3D printing. Maybe I can find someone who has done it successfully.
@@TeachingTech Have you looked at filastruders stuff? im not sure how accurate it is but Ive seen it around
I second Hans. Personally if I had so much plastic that it would need to be crushed, I'd definitely try to do extrusion for something like 20mm round pipe or maybe something like 20x20mm extrusion to use with smaller lathe or other suitable builds. Of course possibly eventually larger extrusions, but then material need begins to be pretty darn high.
@@TeachingTech do u have your modified firmware that you used on the ender 3 for the BLTouch and the filament runout sensor that you used in this video th-cam.com/video/gwHpXaj_6xE/w-d-xo.html
@@TeachingTech Precious plastic extruders put out too much material, and is better for injection molding type setups... The Wellzoom extruders work pretty well though...
great video, thanks for sharing!
I'd also love a video on the extruder they offer!
Tenia el mismo problema con el motor, y justo hoy que pensé que podía ser algo del cople boom resulta que si. Gracias vato.
Nice jacket...
Regards from Brazil
RACKIT is awesome - I would suggest using the securing pins though - or similar, especially if the shelving has any chance of moving around, as movement on one end will torque the frame and can pop the tangs out.
HAHA Classic Aussie OH&S - "Promptly jumped up and down on it...!" - yep she passes!
Looks like You as I do Pretty much live in Bunnings - Connect-It is my favoured Aluminium extrusion from Bunnings for small bits and pieces, and for More range and higher quality/Larger pieces - Action Aluminium in Bayswater North.
Great Vid.
Frustrated with a failed print, "Shred it" lol. Great video, I want one : ).
Nice job.
The coupling distance between the shredder and the motor too wide creating twist on the coupled shafts (shear torque). Reduce the gap, bring them closer and you get robust torque.
This guy knows. Also pins or keyed shaft.
Great ! Simply great !!
Love the channel I've got a ton of good info from you. Something you might look into is a hydraulic coupler. When it jams it won't be a sudden stop for the motor and would give you a little leeway
The best intromusic ever hearn at yt
In the video at the end (12.17 in the vid) when it shows the original coupler, it looks like they had taken a grinder and flattened one side of the shaft so it would be the shape of the letter D, tool steel coupler and grade 8 bolt should hold up pretty good. If you knew someone at a tool shop and they had a broach tool to cut a key way into both shafts would be the best bet for success. Just a thought.
Хорошая идея с мотором!
Mate if you lived in the southern suburbs of Melbourne I would weld the coupler for you. However, as people have said the correct way is to use a keyway, bolts are designed for clamping force, not sheering (sideways) force. An alternative you may consider is press fitting. Get a metal round and drill it to smaller than the shaft of the motor and then heat it up and press it on the motor shaft. When the part cools down you will get a nice strong friction fit...
Nice réalisation
Having built the precious plastic shredder myself, we had the same coupling issues. As for the coupler, have a look at HRC couplers. Can be pricy, made of cast iron, but it will withstand the force. As for the arbors, you can combine some solutions : keys, milling a flat part, locking nuts, pression screws... We also killed m4 m6 and m8 bolts before giving up and going all the way to the HRC cast iron coupler. Good luck with your machine :)
You could probably repurpose the spool for the steel toe table as a coupler for the shafts since it may have came keyed for the winch motor.
Woot, thanks for the shoutout! :)
Can't wait to see the extruder side of things, love love this project!
yes can use flange coupling and the shaft to keyed
I suggest you use gears to transfer torque instead of a coupler. But make sure the gears are close to the motor end of the shafts to avoid deflection. You'll get an even better result with something like a 2:1 or 4:1 gear ratio. Metal gears of course.
Guess the motor with the gearbox looked very appealing after all that effort he put into it.
Hi, as others have said your best bet for the coupling between the motor and shredder would be to get a key way or flat machined in. It might be worth trying to put some gritty material in that flex connector such as diamond or carbide lapping paste to increase the friction between the shaft and coupler. As a side note, if you do end up getting a key way machined in get them to remove the section that you've drilled a hole in as it will most likely be your next failure point.
I need this in my life!
Hey Michael, this was a very good video about shredding failed prints! Now find a way to melt it and make it into a filament
Your Senna jacket is my favorite.
I’m very interested in an extruded solution as well. Cheers
Cool man, now to try to make filament
I have been researching them and will visit a site near me. Cool idea.
At 4:11 in the video you can see a rectangular chunk of metal set into a slot machined into the shredder shaft. A similar slot is present in the spool. And that rectangular chunk of metal that ties the spool to the shaft is the drive key. The drive key not only couples the two pieces together, so they rotate without a lot of play, but the drive key is a deliberate point of failure -- the drive key can shear (fail) before either of the two elements the drive key couples together are destroyed. Think of a big motor in a boat, and a shaft with a propeller on it. If you have a really rigid coupling between the output shaft of the motor and the prop shaft, if the prop binds up, something is going to get destroyed -- either the prop or the motor. Have the two shafts coupled using a drive key that's of a metal deliberately chosen to be not as strong as the shafts, if the prop binds up, the drive key will (hopefully) shear before the motor or the prop get destroyed. Drive keys are easier and less expensive to replace than motors or props.
I'd love to have a key but I don't have a way to machine a keyway at this stage. Thanks for the detailed post.
For a serious setup, look at the motor's duty cycle rating. A hoist usually runs briefly then sits, so a hoist motor is likely rated something like 5 minutes on, 30 minutes off. It costs more to add extra copper etc. to prevent overheating in continuous duty and the motor will be bigger and heavier. Customers usually won't check on this and pay more for a continuous-duty motor (and why should they?).
Well done! While I look forward to the home extrusion setup, I get the sense the consistent filament diameter is very challenging. It would be GREAT if you could take the bag of shredded plastic bits to a recycler, but at least here in the US, I know they won’t take them with our standard home recycling service.
Great work and very inspiring. Nice work with the hopper design. I’m motivated enough to try building one myself now and am starting the research. If you have any updates on the coupling solution I’d love to hear about them.
Sick Hoodie!
It's amazing what you're trying to accomplish here.
Try to collect plastic each on its own color.
Also I'm thinking at juice plastic bottles as Pepsi, Cola or water plastic bottles can be transformed in filaments.
Perhaps the way of printing filaments should be rethought so that the printer no longer has problems with printing depending on the type of filament (PLA, ABS ...). In this way you can recycle any type of plastic...
It would be something amazing if something like this could be achieved.
Congratulations
Yesss finaly I have been waiting for somebody seriously tacle the recicling dilema
More resources from others in the description.
Recycling dilemma? Burn it, it's the best way to recycle anything made from Carbon, it's literally the best way, always, if I was rich enough I'd build a massive biosphere greenhouse and pump it full of CO2 and create a 78/20/1 atmosphere inside it, so that it would be superoptimal for growing Trees, wheat and other plantlife. And I'd prohibit the existence of ferns anywhere near it. Ferns are the worst plant life on planet earth, depleting the atmosphere on precious CO2 and turning into oils after 50 million years and the shit grows almost endlessly and faster than you could imagine, if for example you had a pond with 1 Azolla plant on it. Let's imagine that the ponds surface is 1 googol square meters, and 1 Azolla plant is just 1 mm^2 it doubles it mass in less than 10 days. So it will cover the entire pond which is incomprehensibly big real fast, let's see it will cover it in, 3490 days. Mind you that's
2248210660446050000000000000000000000000000000000000000000000000000000000000000000000 times the surface area of Planet Earth. In less than 10 years... The Azolla fern is said to be the sole reason for the lack of CO2 in our atmosphere. It quickly outgrows anything else that lives on this planet.
In the past when the North Sea was a lake there was a single Azolla drifting along, and we had roughly 7 times more CO2 in the atmosphere than we have now, and in less than 3 years it had drained the CO2 levels to such a point that itself couldn't extract anymore CO2 out of the atmosphere efficiently. Mind you it doubles it's biomass in 3 days in perfect conditions.
9:37 Kindlehill?! Blue Mountains represent! Good use for the Gazette lol
I'm not experienced, but my first thought to recycle plastics would be to apply just enough heat to soften and use an auger to extrude out any general shape... Like a meat grinder.
I really appreciate your jacket/hoodie... I'm also can of Ayrton Senna. I'm Brazilian, btw
Neat what a great idea
Great idea, a winch, l was wondering how to make my schredder, completely forgot l have a brand new unused 1000 kg winch in the shed "laying around".
you could add an arduino or something as a control board, along with some sort of rotational sensor, then program the arduino to reverse for a second then continue forward when it senses the shaft stall.
boom, automatic shredding even on really tough pieces.
you could also give it a shut off timer, so in addition to simple on/off, you could just hit a button to set it going and it'll shred for some amount of time. maybe have it reset the timer whenever it senses the rpm go down.
GOOD JOB GOOD TRY MAN KEEP IT UP
Oh No, your hand....😱, stay save bro
Very interesting. I am interested if the high tensile bolts hold up. You may need keyed shafts or as others mentioned gears to reduce the force on each shaft.
Dave.
Yeah a video about making filament from those pieces would be nice
In my calculation, overall cost for this diy shredder is enough to buy u a cheap chinese industrial shredder machine 😊🥂
i don't know how to say that without sounding rude but
do we (3d printing dudes) give a fu** about the cost per things of self made products over cheap chinese crap
@@coced its ok dude. U are free to voice up even its sounds rude. Every people got their very own opinioin. Well dude, not all entire people have "a lot of money" to spend like u perhaps. Be smart to spending every single pennies we had dude 😉. That crap u mentioned giving most of us a great result and its proven way better in cost effective. Most of DIY projects are attentionally to educated ourself and the most important is to cut off as much as we could the cost ! Remember that ! 😷🥂
@@coced Yes, "we" do. Not everyone's a fan of throwing money in the trash.
It makes literally zero sense to go and spend $1500 for what is essentially ONE electric motor with zero electronics attached to a couple of spinny metal bits. You could probably get similar results to his by just running the plastic through a cheap wood chipper and save more than $1000 and a lot of hassle.
If you're gonna DIY something it needs to come out either cheaper or significantly better than what you can buy, otherwise there's no point.
@@coced I'd bet your 3d printer was made in China - even if you assembled it yourself, the parts probably came from China. I can understand your conundrum though; it is a tricky proposition to write presumptuous racist comments that are littered with expletives without sounding rude. Better to remain silent and risk people thinking you are an idiot than to speak up and remove all doubt.
@@mrtea3122 how was that coment racist
Your a clown
If the torque on the motor isn’t enough you can always get a gear reducer and slap that on your shaft. With something like 1:3 you won’t have any trouble grinding any plastic you can find, or even wood. And also, instead of bolts, use heat treated thick pins instead, they are made for these types of work and won’t break as easily.
Hi, I’m curious as to the coupler solution you finished up with, can you give some detail. Cheers. I have followed the precious plastic journey and you are the first creator i have seen using any of their equipment 👍👍👍.
One thing I would love to see would be a cover-switch, as in a safety cover for the shredding mechanism as it will chew anything that might fall inside, which turns on the shreedder when you put it into place. Just like that, it doesn't work when its unsafe. It would take care of the mess too.
"things have escalated" immediately made me laugh. Yes, it rather looks as though they have. In 6 months i'll not be surprised to see you posting an update while wearing a hazmat suit from behind a blast shield.
6:22 "Now I'm not the best at jigsawing" *proceeds to make 8 nearly perfect cuts.
I would be more efficient to build a 2 stage shredder. 1st stage would shred into larger bits but would put a lot less strain on the coupling, motor, etc. The 2nd stage would take the 1st stage bits and grind them to final size.
The drawback is this would be more complicated to achieve.
Not by much... I mean he could use gearing for that. It's not that difficult.
Wow! That really is a beast. The coupler could be made from thicker 'tube' and high tensile pins perhaps. Maybe some interlock switches on the doors, just to be safe.
DEFINITELY some interlock switches on those doors! I looked at that swing-in side panel when he pushed it in and felt sick to my stomach. LOL.
@@MyName-tb9oz I confess, it made me wince a bit too. Obviously Michael is very safety conscious and knows what he's doing, but it never hurts to be sure.
Just a thought about a universal coupler....what about a steering shaft coupler as used on earlier Holdens just by the firewall. About the right size from memory. They were mighty strong for their size.
Being in Aus that might be something I can track down. Thanks for sharing.
Teaching Tech yeah Im across the pond, had a few thought you may be familiar lol
I like it how pretty much every step of the way it was like "Luckily it was just the right fit!"
Man, Australia really is upside-down.
You should also buy or make filament extruder using this same motor
Is the shaft on the shredder cut for a key? If so, run 2 sprockets and a chain, or 4 sprockets and 2 chains.