Plastic Plate Press, semi-DIYsemi-professional

Precious Plastic Machine Development
#1

Hi, I’m Mark, An Industrial Design Engineering student.
Currently, I’m working on my graduation project, the design of an Open-source plastic plate press for bottom-up recycling in low resource areas.

I’m planning on finishing v1 of my design before the end om May, this year, but a lot has to be done still.

in a few weeks I’ll start the real design work, and around the end of march I’ll start building a prototype.

But first I need to find out what people expect from such a machine, this is where your help comes in. If you are someone that would like to recycle plastic waste through use of a plate press, please help me and tell me what I need to know. To make it easy I made an online survey: https://mark171.typeform.com/to/yrgyP5

I’ll keep you posted on the results, developments and creations in future posts.

25/01/2018 at 12:23: Up til now I started collecting and small-scale experimentation with a panini iron.

07/03/2018 at 11:11: I’ve done a range of experiments, Gathered survey results from around the world, set a goal and now I’m doing actual design work. scroll further down this Topic to see what I’ve shared so far and feel free to comment, all help is very welcome.

03/12/2018 at 18:42:

since today, all of my documentation is publically available here

I did this project for and together with the MMID Foundation so make sure to attribute to them and me if you do any publications, as it says in the Creative Commons Attribution 4.0

This nicely rounds off this project and since I am now working on the sheet-press at V4, still sponsored by the MMID Foundation, I’ve started a new Topic to keep you posted on all developments.

4032×3024 319 KB
4032×3024 319 KB
4032×2286 351 KB

#2

haha good start! 💪

#3

Hi
If our oven is a bit bigger than the PP Video examples and we want to make a compression press plate larger than the DH Blueprint 250 x 250 x 3
Could we go wider, longer fr example 350 x 350 x 3, any thoughts?

#4

Hey everyone for further questions about the V4 development of the Sheetpress, you can post below here (best option so everyone can benefit from our discussion), inbox me here or reach us on discord https://discordapp.com/invite/AKuxkpx

#5

@pradyumnakrao

thx for the kind words!

I’m happy to help,
also I’m starting my own business building presses, ovens and sheet-pressing tools and making sheets and products from sheets.

So when the time arrives I could build something for you or come over to do a build on site.

For the smaller size a single jack could work, I used a vice screw for 50×50 sheets

for 60×60 I’d say minimum of 6.5 ton

#6

Wow Mark firstly I would like to thank you for the amazing work you have done developing the sheet press and the documenting it so well and making the large scale prototype. This looks stunning and opens all kinds of doors to make much larger objects with.

 

We have a slightly larger oven than usual, we can fit in a mould about 60x60cm big, one of the doubts we had was that, do you think as we don’t have the largescale size of a sheet press that we could use a single heavy central jack and what kind of tonnage would you suggest for that as well. We know that you might be busy so if you do see this message would be great if we could hear back from you. This is more for testing and hopefully, if it all goes well we could be looking at building the larger scale one.

#7

Congrats for your graduation, @mark! Such a great job there <3

We’ll be trying to replicate this in Brazil really soon, and hope to give valuable feedback to the community too.

#8

@hadin & others

since today, all of my documentation is publically available here

I did this project for and together with the MMID Foundation so make sure to attribute to them and me if you do any publications, as it says in the Creative Commons Attribution 4.0

This message nicely rounds off this project and since I am now working on the sheet-press at V4, still sponsored by the MMID Foundation, I’ve started a new Topic to keep you posted on all developments.

#9

Wow, truly amazing work! Feeling really inspired by this 🙂

It would be very interesting to read your thesis, did you ever post it? Also did you post any technical drawings of the machine?

Thanks for this, and good luck with the v4!

#10

I’m currently working on tests and improvements for the press at Precious Plastic V4 In Eindhoven.

In the ideal scenario in which you have 3 moulds, you’d be able to make 4 plates in 8 hours

PET is on the test list but haven’t tried it yet

I’ll start updating here again as soon as I’ve found noteworthy insights and results

#11

Awesome job!  Have you tried using PET to make a panel yet? How many panels are you able to product per day?

#12

@timslab looking good!
i’m looking forward to seeing your plate results!

#13

Awesome documentation!

#14

Thanks for all the info @markbertbach

Currently building a smaller version of your mould for some 300x400x5mm sheets. I’ve made a couple adjustments based on your large aluminium mould and now tweaking it for mild steel with some DIY cut-off edges. Will post in this thread how it all works out 🙂

#15

@abdidesign

Thx for the compliments!

AT the end of this month I have my graduation presentation, around which I’ll also discuss how the design is going to be shared and what will happen to the machine that I built. Afterwards, I’ll maybe join the precious plastic Army in Eindhoven to work on V4 and improve or make a new press design.

And I’m also looking around for a job 🙂

#16

I would be happy if I had this machine in my workshop

#17

wow very nice mark….respect.  what is the next plan.

#18

Really nice work man!

It looks like you changed up your mould quite a bit, how come? From aluminium → mild steel?

#19

This is amazing – I don’t know how many lifetimes it would have taken me to figure all this out. Thanks so much.

I’ve got a bunch of questions again and I’m sure you’re quite busy, so no worries if you don’t respond right away

What was the 5 Bar suggestion based on?

Does it change for different types of plastic?

Surely the thickness of plastic matters too – 1mm would presumably need much less than 50mm, regardless of surface area. Is there some sort of scientific guideline/formula for it?

You settled on 1.8 Bar based on success at that pressure with the book press.

What criteria did you use to judge it to be a success? Just visual inspection? Lack of bubbles? Proper shape? Actual stress testing the material properties?

Did you try less pressure to see if it would work? More pressure to see if it would be better?

I ask all this because I have been browsing all sorts of plastic manufacturing textbooks recently and they seem to say, in accordance with intuition, that a visual inspection is a very poor and misleading way to judge output quality – differences are at the molecular level and show up in stress testing.

Ive got other questions and thoughts on the jack, frame design (steel thickness requirements), moulds etc… But will leave that for later.

Good luck with finishing the thesis! We definitely need to chat when you’ve got time – there might be a job in it for you scaling this up in the developing world as well as helping us tinker with other stuff to help improve lives in a cost effective, creative and empowering way

#20

Hey there, I have a slew of questions/thoughts now that I’ve reviewed the posts and videos a few times. Hope you have time for them!

I noticed you previously used a book press. I was thinking of doing something like this with a single jack. How did that go? Why did you switch to the 4 hydraulic jacks? Was the pressure insufficient?

What sort of pressure are each of those jacks capable of? Do you have any rationale for what pressure is needed or did you just choose those at random? Do you think the rig you built would be able to withstand more force?

I bring this all up because any literature I can find on compression moulding seems to say a minimum of 200psi is needed, which would be over 200 tons of pressure for a sheet that size, which is obviously absurdly out of reach for us. However, most literature on compression moulding is for thermosets, as thermoplastics seem to not be done this way, so maybe that makes a difference. I’m just trying to get an idea for what sort of pressure I should try to build for.

You said somewhere that the thickness of the sheets is variable, which suggests you just allow the pressure to do its thing rather than have some sort of stopper in place to make an exact height. This is probably the correct way to do it, as limiting the height would limit the pressure on the plastic and presumably result in a worse product. However, you also said there was some thin flashing, which is typical of a compression process, but also means that the pressure on the plastic is literally leaking out.

I suppose a real industrial process would use a specific measurement of plastic and the mould design would allow for flashing while also keeping the correct pressure – perhaps just a trial and error process for the likes of us?

Have you tested the sheets in any building processes yet? Do you think they could benefit from additional pressure? Could you get away with much less?

Or am I overthinking all of this and its a forgiving/flexible process? Whatever the case I’m just going to tinker with some scrap metal and see what happens. But I’d like to have at least some rationale for what I’m doing.