Introduction: Plastic Shredder
Unlike everyone else, I was never attracted by expensive gizmos and gadgets. One reason is that I couldn't always afford them, and other being my fascination for building and creating stuff for myself from scraps and so-called "waste". For my latest project, I wanted to build something useful and something which could benefit the society as well. Reading about the various cases of the ill effects of plastic in the newspaper every day, and crossing the garbage dumps and general waste on the roads in Noida, some of it is from the packaging of "expensive gadgets", I wondered if I could do something about it. I went online, did a little research and came across a website called preciousplastic.com (https://preciousplastic.com/) where a couple of people from the Netherlands have made the designs and blueprint of a "Plastic shedding machine" public. They've created a community with the aim of increasing awareness about plastic pollution and the machine is a very useful way of recycling plastic for better use. And so, I decided to make use of my creativity and started this project with the aim of reducing plastic pollution in my city.
You can download complete kit through this link >> ( https://drive.google.com/drive/folders/1sHatOvjauBHwbZ2ZjkTPTOHe6rVlrwW0?usp=sharing )
Step 1: Materials
For this project, you will need:-
* Stainless steel sheet AISI 304 3mm, 5mm & 6mm
* Hex rod 27mm
* Round rod 25mm ( According to the gearbox )
* Pillow block bearing ID 20mm
* 10mm Threaded rod
* Mesh
* Metal sheet for hopper 1mm
* 3 phase 2 Hp motor
* 70 rpm 2 Hp gearbox
* 1.25" square pipe for the base
* 1.25" x 4mm angle
* Forward and reverse switch
Step 2: Designing and Cutting
Next thing you need to do is cut all the pieces for the shredder using laser cutting or plasma cutter. CAD files are available and you can send them to your nearby laser cutting shop. Once all the pieces are cut you need to smooth the edges using sander so that it fits altogether nicely. These pieces are like a puzzle and I have welded 3mm pieces as shown in the picture. This is the core element of our project which does the magic by converting small bottles into small flakes.
You will also need to taper holes in the 6mm sheet to make some space for the bolt head. I have used a 20mm drill bit for this.
Step 3: Axle for the Shredder
Round the hex rod from the ends. Space needed in between is 145mm for blades. You can follow the pattern to arrange blades using dots present on it. You can take help from the video. You can also use a different configuration.
Step 4: Assemby
Cut 4 pieces of threaded rod of 8" and arrange the blades as shown. Try this video for help and better insight.
Make sure everything works smoothly. Tighten up the bolts and weld the joints for the 3mm sheet. You will need a small mesh that determines the output of the shredder.
Step 5: Engine
Next thing you will need is a motor and a gearbox which will provide power to our shredder. I am using a 3 phase 2 Hp 1400 rpm motor which is the minimum requirement. Gearbox is of 1:20 ration so the output that we will get is 70 rpm. I have made a shaft and coupling to connect it with the shredder. I have not shared the specifications as you need to make yours according to your requirement and type of gearbox.
Step 6: Base
Make a base with 1.25" square pipe and try to make it low so that it is stable during the process. Specification of my base is 40"x 15" and 30" height. I have used 2" long & 4mm thick angle to fix shredder and motor with the base.
Step 7: Hopper
Next thing that will need to make a hopper through which plastic goes in and making a square one so that we can create a little pressure from above. I have used 4 x 6"x 17" sheet and bend it at one end to screw it with the shredder. After which weld it clean and nice.
Step 8: Output
After paintwork and electrical connections, it is ready to shred some plastic. I have tried a Cocola bottle without the mesh and results are quite good.
Take a step to save our planet.

Participated in the
Metalworking Contest
23 Comments
Question 3 months ago
may I know from where you got the gearbox :)
11 months ago
hi
what type of material you cut ? how much the tensile strength for that ?
how you decided and you select 2 hp for motor ? how you got output 70 ?
could you share us the dimensions please
1 year ago
Could u please Send me SolidWorks Design?
Reply 1 year ago
yeah i need the solidwork design too for my final year project
1 year ago
Hi thank you so much for the good job I need real help on this project I bee the machine please send me the blue print
Question 1 year ago on Step 2
Hello. Please send me the exact measurements of all the things.
we have tried many different measurements but none worked???????????
?????????????????
Answer 1 year ago
Search for precious plastic Shredder
1 year ago
hi, sir.I have a question is there a computation on how you get the size of the cutter..
2 years ago
hello..raghav....m going to start working on solid waste management...can this shredder machine shreds municipal waste into small pieces...may be less than or equal to 2mm?...
Reply 2 years ago
Hello,
Yeah, it could be done and you can reach me at raghavsharma2596@gmail.com if need any help from
Question 2 years ago
Hello,
I have a question for the volume of plastic fragments after shreddering the bottles. is there a method to get a specific final volume? how should i specify this volume?
Answer 2 years ago
May I know what volume you are trying to achieve?
Reply 2 years ago
i'm studing, and i'm workin on project of the end of year so i need someone help me to find how can i identify the volume of flakes after shredring ..please would you help me ??
Reply 2 years ago
i forward to achieve 7mm
Question 2 years ago
Hi, I'm trying to design and make a paper shredding machine but i can't achieved it can you help me with the design
Reply 2 years ago
https://www.youtube.com/watch?v=zubmkHMRP3U
3 years ago on Introduction
I am definitely planning on building the shredder but can't seem to get the drawings to download. Are the links still active? Thank you
Also I don't have 3 phase power available. Is that going to be okay? How should I adjust the motor size? Thanx, Craig
Reply 3 years ago
Yes, the link is still active and you can use a single phase motor of 2 Hp
4 years ago
Good job! Voted for metal contest! :D
What are you doing with the pastic after it's shredded?
Reply 4 years ago
You can process it further using different machines. Please try this website for better insight >> precious plastic.com and thanks for voting.