flo-2

warrior

25/11/2017 at 15:02

Wow @jegor-m that looks really nice! Especially for the first few trials!

andyn

warrior

25/11/2017 at 15:02

Good first results! What is the thickness of the coasters ~6mm?

Can you show us the mould attached to the injection nozzle (held by pressure)?

jegor-m

warrior

25/11/2017 at 16:02

@andyn, sure, will post it when I get a chance.
Coaster thicknesses: PP – 8mm, HDPE – 6mm.

jegor-m

warrior

05/12/2017 at 20:50

🌎Update N.15

A quick update:

1. NGO registered; Bank account registered; Meeting the representatives of the Producer Responsibility Organisations soon.

2. It has been a while for sheet press action for us. We fired up the oven, got some plastic in, waited a bit and pressed the molten pile between the metal plates in the sheet press, like before. This time we used regular office markers (Photo 1). You might have seen these shredded in the earlier photos.

What we got is shown in Photos 2-3. Thin sheet of PP, very multicoloured. Thickness 1-2mm. On the photo you can see some wrinkles and creases. This is due to top metal plate sliding and baking paper creasing while it was transported from the oven to the sheet press (literally 1 step, managed to mess it up)

The apparent dirt is not dirt at all. It is all the black ink that you can see on the Photo 1. The barcode and the text got shredded and are now inside the plate. Looks like dirt. Not cool.

Next, Photo 4 is a quick mock-up of what a wall clock made of this sheet would look like. We have not yet decided to turn it into the wall clock though.

3. Photo 5 is a teaser for our extruder. It just needs some drilling, polishing, electrics set-up, painting, re-grinding, re-painting and testing.
For now: we increased the barrel diameter, auger bit is 32mm in diameter. Will see how it turns out.
FYI, on the last photo – it is Max ( @maximmm ), add him as a friend. He’ll be super happy.

waterguy

helper

06/12/2017 at 01:07

Awesome!I could watch that for ages.

dbougas

dedicated

25/12/2017 at 23:34

Hi
Question on your remark concerning the overheating with bubbling…
Do you mean that over temperature result the bubbles? Not only the burn…
Thanks for your feedback
DiB

jegor-m

warrior

27/12/2017 at 09:08

@dbougas,

Yes, there are a couple of factors that contribute towards bubbling.

If you’re not compressing the plastic for example, then the air trapped between plastic pellets just stays in place and eventually turns into bubbles.

If you badly overheat the plastic, then bubbling will not be a problem as you will simply burn it. But if you go high above the melting temperature, you might get more bubbles in the plastic, even if compression is involved.

PS. Please use @ and a nickname to mention a user. This allows monitoring updates more easily.

jegor-m

warrior

10/01/2018 at 11:17

🌎Update N.16

A friend of ours gave us keys to his small damp garage in Tallinn that we are going to use for production. In a month or so we will try and get the machines in and will be ready for visits.
In case you’re planning to come over to Tallinn 🇪🇪, give us a shout.

jegor-m

warrior

16/01/2018 at 22:17

The garage is slowly getting into the right shape, machines coming in..

davehakkens

warrior

16/01/2018 at 22:22

yeah!

dbougas

dedicated

17/01/2018 at 00:38

👍 really cool!

spin

starter

17/01/2018 at 17:49

Great work so far, I will be keeping an eye out on this thread to see how your machinery and processes progress. :o) I hope setting up your workshop in Tallinn is the start of something new and exciting for you.

caymans

starter

19/01/2018 at 11:58

@jegor-m This is a really great story, full of details. I have a question, for big pieces of plastic recicled by extrusion (bigger than the aluminium can) you mentioned that it has to cool down slowly (p.e. in the oven), right? If we apply some pressure and always with a controlled temperature (I mean avoiding overheating), do we still need to cool it down slowly?

Thank you,
José

xxxolivierxxx

hero

22/01/2018 at 00:19

I hadn’t look at this thread, you got a great information repository here. I had the same problem with PET bottles sliding into the edges of the shredder knives. I was planning to melt the bottles in an oven prior to shredding them to avoid this issue but haven’t had a chance to test this out yet.

jegor-m

warrior

22/01/2018 at 12:13

Winter in Tallinn = cold. But we are working!

carlf

helper

22/01/2018 at 18:57

Yeah, same here in Dresden. Freezing cold…
Our solution -> Building the Compression:)

dbougas

dedicated

22/01/2018 at 19:32

And you have pictures?

jegor-m

warrior

22/01/2018 at 21:45

@dbougas,

Of course. 🙂
Here is a teaser for the upcoming post about coaster injection. Stay tuned!)

jegor-m

warrior

25/01/2018 at 22:20

🌎Update N.17 (1/2) – PP Coasters

Over the last couple of weeks we have been testing the injection machine. For that we made two metal moulds and one acrylic mould (plexiglass).

What you need to know is that the ambient temp. in our garage is about 0°C.

The first photo shows the coasters we got.
Pictures 2 and 3 show the first try using metal moulds. Temperature set for a bit over 200°C. This is mostly due to the fact that it cools down quite fast in such a cold air.
Result – pretty nice coasters with minimum post processing / finishing up.
What could be done better? – wait more time to get uniform melt – better surface.

Pictures 4 and 5 show a second attempt. Process temperature was lowered.
Result – as you can see both of the coasters are not finished. This is mainly due to the fact that the mold is cold and plastic cools down and solidifies before reaching the furthest wall. Before you say it, we actually wanted to put the injection point to the side, to get plastic to flow in weird shapes and colours. The smaller coaster, if it can be called a coaster, has dark lines. This is because of the leftovers after the previous batch (pic 2 and 3)
What could be done better? – Faster injection; Longer wait;
Also a good idea is to add an indicator hole, that would show that the mould is full and it is time to stop pressing.

*acrylic mould has not been tested properly yet.

jegor-m

warrior

25/01/2018 at 22:39

🌎Update N.17 (2/2) – HDPE Coasters

Next was a test of grey HDPE. Three temperature sets were used (170/180; 190/200; 220/230 °C). The results are shown in the photos attached (in the same order).

Photo 1:
We added some pieces of bottle caps (white, blue and yellow) just to give it a bit of colour. At least we tried. This set of coasters got a very rough texture. It was very hard to push into the mould.

Photo 2:
Surface flat and low roughness. Warping due to increased temperature becomes visible. Injection was not performed in one movement. It was paused for a second and then continued. This is clearly seen from the injection lines on the coaster. Second one is not filled as it got too cold to flow.

Photo 3:
Our metal mould is far from perfect. If more plastic is squeezed into the mould, it would fill every corner. This try was done with the most heated HDPE, hence better flow. The overheating warp is quite bad on this one.

What could be done better?
Perfect temperature range is yet to be established.
Injection has to be in one quick move.
Indicator hole should be a good way to see if the mould is full.
Ambient temperature has to be adequate.
Mould temperature to be at least 20°C (better if 30-50°C)

Photo 4:
All the coasters up until now. Only 3 of good enough quality.

ashrak

helper

26/01/2018 at 01:59

Nice work, I like your documentation.

dbougas

dedicated

26/01/2018 at 08:04

Very good…
👌👍

magnoliascaboose

starter

29/01/2018 at 00:48

Wow!!! I would love to start this where I’m living. My idea was to collect plastics that have washed up on the beach but after reading realize certain plastics melt together more smoothly than others. Gosh where do I even begin?

jegor-m

warrior

29/01/2018 at 08:01

@magnoliascaboose,

General practice is to avoid mixing various types of plastic in one item as it makes it unrecyclable and cannot guarantee item’s structural integrity. It might just fall apart as the bits won’t stick to each other.
Smoothness is mostly controlled in the fabrication process itself through setting the right temperature; having a smooth mould etc.
The first step is to separate the plastic. By product type first, then with some research by material type as well.
Also don’t forget there is so much information here on the forum, look something up.

Good luck with your recycling!

jegor-m

warrior

30/01/2018 at 22:17

🌎Update N.18 – Extruder

Eight months ago we had our first meeting and a casual discussion about the possibility of starting a local Precious Plastic branch in Estonia.

Today our garage has an injector, shredder and an extruder. The latter is still to be tested with plastic.
Future plans include building a compression machine (fancy oven) with rotomoulding capability, a small PET bottle shredding machine, may be also a long (limousine) oven for the longboards and a vacuumforming machine. We’ll see how it goes.

ashrak

helper

01/02/2018 at 15:50

Awesome!

dbougas

dedicated

05/02/2018 at 23:49

Like always awesome!

jegor-m

warrior

19/02/2018 at 10:04

🌎Update N.18 – Bottle caps

We sorted the bottle caps by colour, with blue being most common.
How do you guys deal with the rubbery layer inside the bottle caps?

Current plastic stock status in the photo.

ashrak

helper

19/02/2018 at 10:41

@jegor-m

How do you guys deal with the rubbery layer inside the bottle caps?

You mean the closure lining material? Here they are not so common anymore, but I do remember them many years ago, are they not easy to pick out by hand?

Also good to know is that the lining should be LDPE.

jegor-m

warrior

19/02/2018 at 11:02

@ashrak,

They are indeed not so common anymore, but we managed to get about 50 from old Fanta bottles and so on. They mostly require some cutting / scraping out with a knife and it takes extra time.