Shredding

Precious Plastic Machine Development
#1

Hello everyone!

I have several questions about your shredders:

  1. How do you clean up shredder between cutting different types of plastics?
    For example you shred bag of PP plastic, and that you wanna shredd HDPE or PS?
    How to remove all small pieces of plastic from the shredder?
    In my case if I even remove sieve (which is not conveniently), other small pieces could be between other metall parts. And the use of a compressor can not always help to blow it out.
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#2
  1. How your work with colors? You presort containers by colors, and that shred them.
    Or your shred all HDPE (for example), and than you sort small pieces by colors.

Another question about bottles, which consist of lid (HDPE, LDPE or PP), bottle (PET, HDPE), and label (LDPE, PP, or just paper).
So you throw fully bottle in shredder, of your remove lid, label before that?

Right now I have piles of different plastic waste, which need to be shredder. And I wonna optimized that process.

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#3

1. it can be a bit gross but I use a propane torch to loosen bits of plastic stuck between the teeth
4.  I had to upgrade to a urethane jaw coupling insert

#4

RE: Broken Steel shaft, 3 reasons why your steel shaft broke:
1. your motor does not have an overload protection or it is set too high relative to the torque it has.
2. you need a reversing function and your motor has to be shut down as soon as it jams
3. you should mount on a steel plate or solid steel bars, if the motor is allowed to torque and essentially bend the shaft and then allowed to continue to run and torque, it will break the weakest link if it has sufficient horse powe, ie, the
bent stressed shaft.
The instructions do not say to mount on a wood plate, do they?  The frame needs to be very rigid.

#5

Answering 4) What type of clutch?

In forum some use the same as you:
http://onearmy.world/community/forums/topic/my-shredder/

#6

Answering 3) How do your operate with your engine?

you can find discution about shredder motor in here

#7

Answering 2) How your work with colors, about bottles, which consist of lid?

some recycling industries in my country, use them all (bottle & lid) “lid” you mean the plastic ring around the bottle neck right? It’s made of HDPE). (video below minute 2:23)

i think it’s because the floating theory (video below minute 6:57) the lid will float on water

#8

Some industries use it directly in extrusion

Some use the super economic shredder that is paper shredder

#9

That’s beautiful workspace, like it 🙂  thank you for the motivation

 

Just reference

Answering 1) How do you clean up shredder between cutting different types of plastics?

Plastic bag is also problem even in factory scale

That’s why dave suggest work partly / in batches (In video minute 2:12)

#10

Actually it is not my first experiment with PLA.
At one of the first versions of my shredder I used PLA made muff (before I found industial muff).
So that PLA muff could easily cut 8mm steel stud.

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#11

😳wow, that’s quite bad…
Couldn’t imagine that PLA would be able to break the shaft, Thanks for sharing!

#12

It seems like PLA is most complicated plastic for shredding.
In shredder it starts heat up, all small parts stick together, and its look like huge gum.
That gum sticks between metall parts, that could damage shredder machine.
In my case PLA broke steel shaft.

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#13
  1. Anyone has autoreverse feature on your shredder, to prevent damage machine when you cut something tough?
    And maybe someone khows how to do such electricity circuit?

Better not to use an automated one, hard to build save, you never know when it decides to run forward again, a few (3) relais and 2 buttons to reverse manually.
When the shredder blocks, push a button to reverse, and be sure you have to manually and on purpose, push or switch the forward start button again.
Just to be sure you do not have to resort the bloody red stained pieces again 🙁 ….

#14

I can imagine that the thin plastic might work between the blades and tangle around the axle. Does this happen or is the shredder tolerance so tight that it cuts the bags as intended?

For my shredder its to thin, gets messy. It helped putting in the oven for a while, to compact it a little.

#15

Great Questions above. May I add another question?
I’ve watched all of the PP videos I can find and read most of the webpages and a lot of the forums but I don’t recall seeing anything about putting plastic bags or other thin plastic sheets into the shredder. I can imagine that the thin plastic might work between the blades and tangle around the axle. Does this happen or is the shredder tolerance so tight that it cuts the bags as intended?

#16

@olce

Compressor airgun doesn’t help with chips which stuck between blades.

#17

Regarding cleaning the shredder :
Just an idea…
Using an airgun (from an air compressor) to blow out the plastic bits when the shredder is running?

#18
  1. Anyone has autoreverse feature on your shredder, to prevent damage machine when you cut something tough?
    And maybe someone khows how to do such electricity circuit?

Like on this video: https://www.youtube.com/watch?v=LuhZM5cP3VQ

#19

1. Disasemble? but that could be a lot of work, clean out as best as you can and hope for the best?

2. I would presort the plastic by type and then color.

3. Non-stop. (depends on the engine)

4. Jaw coupling (as your image), allows for some misalignment.

#20
  1. What type of clutch do you use in your shredder?
    Dave’s similar or factory clutch?

I have changed several types of them – right now I use taper bush type.