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warrior
16/04/2019 at 15:33
3

Hello everyone !
Sorry for the long time since i have given you guys an update on what’s going on on our side ^^

So after having experimented manual extrusion we realized that we could explore a bit the couloring side recycling.

The main plastic product we use is pallet wrap, which is LDPE and can be transparent or black. The transparency is due to lack of pigmentation (and thickness being very small), it becomes white once melted (and therefore much more thick as when it was just a sheet)
Understanding that principle we started adding bottle caps to the process. Once all is melted, you can “easily”(need heat-resistant gloves though) mix it with your hands. The more you will mix and the more the colour will be homogeneously blended. The more you add coloured caps (of the same colour), the darker your color will be, the less the brighter. You can also mix colours as you would with paint. I managed to create a nice homogeneous purple mixing red and blue together ! 😀
The first problem you may encouter while trying out that process is that the plastic will stick to your gloves. You should wait a little bit for it too cool down (right before mixing) so that the most exterior layers of the melted plastic is already hardened and therefore not sticky.

 

 

Then lastly with help of Clemence which i met through PP map (thank uuu!) we tried out silicone moulds;
Why silicone ? Isn’t it going to melt ? No ! If you read the PP Manual in the kit, you should know that there are 2 big families of plastics; thermoplastics (which melt at right temperature), and thermosets which can only take shape once. The temperature of melted plastic won’t affect it ! So idea is the following :
Create an item (sculpture, 3Dprint) or just any type of objects :p
Take the impression of it with silicone
Create a casing
Ready to use as a mould !

 

Here is a little rhino we made 😀

Our extrusion machine is almost ready, just need to find someone to help out with the last electrical & electronics parts 🙁

Cheers !

ps : i am sorry for the name of the original post, i didn’t know at that time that other french projects were launched; so it’s PP Sartrouville 😀
u can check us out of FB or insta

Attachments:
warrior
09/04/2019 at 11:56
1

Hello bois & gurlz !

My turn to ask (if still possible :D)

1: http://www.ppsartrouville.fr
2: sartrouville.preciousplastic.com
3: 155.133.132.5
4: <3

warrior
04/04/2019 at 17:47
3

or to increase the size of the planter, just reduce the overall thickness of the product; shouldn’t that work easily?
edit : woops just read last post this thread after posting 😮

warrior
01/04/2019 at 17:03
1

hey, haven’t extruded with PP machine yet (but will do VERY soon)

Only remark i can give is
HDPE is supposed to be more dense than LDPE, so HDPE’s melting T° should be higher than LDPE and not the opposite ?

You could try LDPE lower and see if it goes better 😀

warrior
01/04/2019 at 17:03
1

hey, haven’t extruded with PP machine yet (but will do VERY soon)

Only remark i can give is
HDPE is supposed to be more dense than LDPE, so HDPE’s melting T° should be higher than LDPE and not the opposite ?

You could try LDPE lower and see if it goes better 😀

warrior
01/04/2019 at 17:00
1

Hey Lynn !

That’s exactly the way i do it ! (you don’t need your mould to be heated as same T° than plastic’s fusing temp)

Though the idea came to us because we didn’t have any metalwork skilset to do the actual PP Compression Oven. Over time we happened to realize that the process goes MUCH faster that way.

 

Following PP machine :
– Preheat oven
– put flakes in mould and put in oven
– wait for plastic to melt
– apply pressure
– turn oven off
– wait for the product to cooldown/solidify

Whereas our system is :
– turn oven on
– put plastic to melt
– only take out what you need to fill the mould
– apply pressure
– after couple minutes, take out of mould, cut off the plastic overload and reapply pressure (otherwise retractation becomes freeform :p)
– repeat !

Main difference is that your oven isn’t turned off & on again for each product (meaning more energy efficient & more products created)

Cheers !

warrior
01/04/2019 at 16:50
0

yeah i tried putting PE film through the schredder and my heartbeat rose instantly !
Though it doesn’t require much strength to make it turn into flakes, it’s so thin that it goes between the different metal parts of the schredder…

I usually just put the film directly in the oven to melt, but i’m trying to figure out a way to use PE film into the extrusion machine 😀

Any photo of your system guenther? I’m curious to see how you worked that through

Peace !

warrior
30/03/2019 at 08:26
1

Salut @vanlandejeremy !
Pour plus de praticité relatifs aux infos françaises, j’ai créé un lieu pour la commaunauté francophone ( https://discord.gg/TfXKRe6 )
Ca t’aidera surement à trouver plus facilement réponse à tes questions 😀
nico

warrior
16/03/2019 at 17:31
1

@macq
Just used the bench+table nonstop during a full week; nothing moved !

warrior
09/03/2019 at 08:06
0

Bonjour Bonjour,

 

Pour ma part, j’ai sourcé mon moteur sur un broyeur végétal dit “silencieux”, assez facile à trouver finalement sur leboncoin;
moteur 1,1kW, 1200tr/min mais y’a un système de réduction déjà présent qui fait qu’on est aux alentours de 70rpm.

Y’a même le système de marche avant/arrière d’intégré !

bon courage !

Nico

warrior
07/03/2019 at 12:00
1

Hello @vertimbale !
The main information you must keep in mind is that all you need to work with plastics is  specific temperature & pressure.

 

The main differences between the machines is the product output you can obtain.

Injection machine has it’s limits concerning big items, you would need a bigger barrel & more manual pressure. The process is a one-shot

Compression machine also limits the size of wanted product due to the size of the oven you use. The bigger oven, the potential bigger product. This process is also a one-shot

Extrusion machine is quite different as it is a continuous system (as long as you continue feeding it with schredded plastic), in that sense, you can push the limits much further (concerning the size of output products)

Hope it helped ^^

 

warrior
24/02/2019 at 08:21
0

@heinrich

be careful of what n°7 you are working with.
n°7 is all other types of plastics. So if you work with PLA (n°7), don’t put it to melt with another type of plastic from category n°7

warrior
24/02/2019 at 08:18
0

@ezeturk hi !

Have you ever managed to do compression without any use  of mould releaser or silicone spray?

we don’t use any of these & have 0 issue..

cheers!

In reply to: Recycled Party Cups!

warrior
23/02/2019 at 06:43
0

recycled PET, as an industrial process, goes through different process, one of them being the regeneration.
We do not have access to that..

Also, PET recycling always uses virgin pellets (new plastic) for the recycled products; and the % of recled plastic is always under 50% (around 20-25%)

In reply to: Recycled Party Cups!

warrior
22/02/2019 at 18:46
2

hey @bauple & @forest !

Plastics… so what is a plastic ? A plastic is : polymer + additives

The polymer can be Polyethylene (PE), Polypropylene (PP) etc.. each polymer has it’s own properties (density, clearness, softness etc…)

Additives on the other hand will give extra properties to the plastic. The types of additives are VERY wide, can be to add uv-resistance, strength, make it easier to inject, cheaper to produce, flame resistant, etc…

Each additive (at least in europe) is more or less regulated into big categories of products, the most strict category being “food grade”; the legislation only permits industries to select additives through their list (1000+ possible additives)

Also, additives always migrate, meaning they get out of the plastics through time, heat, contact.. and each additive has a treshold which should not be exceeded (measurements are based on the usage of the product; single use plastic = 1 time use migration treshold measurement)

Soooo when you are putting one type of plastic to melt; there are different additives which may react to each other, and your long lasting “food grade” recycled plastic product will slowly but surely migrate its different additives to the consumer
To limit this effect i would recommend you to have an effective ‘sourcing’; meaning trying a specific product at a time and, if it goes well, put it on a green list; otherwise, red..

(What i wrote is just based on the research of have been doing the past year on the subject, making mistakes, learning from them and searching more & more, which might not be the case of everyone launching PP projects _to answer to the “food-grade” recycled products on the bazar_ ; if any polymer-specialist would mind adding their intel on the subject… 🙂 )

In reply to: Recycled Party Cups!

warrior
22/02/2019 at 09:31
3

Hey @forest !

Though the idea seems good in the first place, using recycled plastics to make “food-grade” products like a cup for example is from my point of view a clear NO-GO!

There is no way you can assure the future costumer your recycled plastic is food safe :'( you will clearly put them in danger
cheers!

In reply to: V4 Adhesives

warrior
22/02/2019 at 09:21
1

Hey @s2019 !

Well the process is quite simple to be honest and follows the principle of thermoplastics recycling;

If you want to work with plastic, all you REALLy need is heat; the right temperature to make your plastic change from solid state to soft/jelly-like state.

 

If you are able to bring that raise of temperature locally, the spots heated will start melting. As soon as it’s the case, put the 2 products together (melted spots being the contact point) and tighten them together.

 

Wait for it to cool down to solidify, tada !

ps : the obvious limit to the technique is that you cannot bind 2 different types of plastics together

warrior
22/02/2019 at 09:15
1

hey @thups
I just noticed this very interesting thread, i’ve been doing couple tryouts with PS

So to answer your question, there are 3 categories of PS
Cristal PS : always transparent
Choc PS : coloured version
Expanded PS : not the same at all; doesn’t react the same when put to heat, it is made of TONS of miny bubbles filled of air(?); check out @coira ‘s tries with Expanded PS on the V4 subdirectory !

Funny enough, i find many similarities between PLA and PS in finished product, the main difference being that PLA’s transparent doesn’t maintain as much when going bigger thickness as PS does

here is a photo of one of our PS products, we managed to put in place a little technique to “block” different colours in the inside (not exterior) part of the product 😀

Cheers !

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warrior
21/02/2019 at 10:48
2

they are called the “Big 6”
1. PET
2. HDPE
3. PVC
4. LDPE
5. PP

6. PS
7. other types of plastic or coextruded plastics (ie:PP/PS)

So PE is a special polymer, as it’s used in many different densities and is communly used in our society (HDPE & LDPE are seperate groups, but there is also LLDPE & LLLDPE) :p
PS has 3 subcategories : PS Choc, PS Cristal, Expanded PS

But the number system is the same for other materials

You really never want to mix different plastics together (but for your info, recycling industries in France shred and melt together PE & PP, they consider it has no impact as long as there isn’t more than 5%PP in the PE flow)

Attachments:

In reply to: V4 Adhesives

warrior
21/02/2019 at 09:30
2

hey @acoira !
have you thought of keeping the plastic/bond monomaterial ?
by heating up locally the plastic, you can fuse parts together quite easily !
i’ve been doing some tests so far with a heatgun and a plancha (to be able to have the same heat applied on the side of my 10cm squares)

Have only tested so far with LDPE and works a charm !

(planning to try with PS & PLA soon too)
cheers !

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warrior
21/02/2019 at 09:21
1

hey @heinrich

concerning films; here is a little trick which might help

film can be PE (HDPE & LDPE) , PP or PS, if your finger can go through it like a vegetable bag from supermarket then it’s LDPE;

PE & PP have very similar properties as they are from the same family : Polyolefine

PS has different properties, the most important one (i guess) to differenciate PS from PE/PP is it’s density. PS (except subcategory PSE) sinks when PE/PP floats in water 😉

Beware of co-extruded products (PE/PS, PP/PS, etc…) and presence of aluminum (which isn’t plastic , duh.. :p)

In reply to: Hello World

warrior
12/02/2019 at 19:50
0

Superbe initiative !!

In reply to: V4 Beam Production

warrior
12/02/2019 at 19:22
4

https://youtu.be/WwBgRuCpYNc

https://youtu.be/JP2Mmf7etGU

Sorry tried to emb it to the forum but didn’t manage to :((

 

In reply to: V4 Beam Production

warrior
05/02/2019 at 19:27
2

@wolfgang haha very nice video, VERY inspiring for low-tech solution !
i’ll scare you with the one i’ll post tomorrow hahaha (i can’t do as long beams atm though :p)

warrior
23/01/2019 at 20:05
0

how much time does it take you to process the “take out plastic from oven and transfer to mould & compress” ?

What is the compression system you are using ? could you send a picture of that ?

it looks like the first photo you sent has a very nice marking; meaning if you want detail marking on your product, you will prefer preheating your mould (lower T° than fuse temp though to avoid stickiness to mould)

PE tends to warp; Also i guess you can imagine PE & PP like a big onion, formed of many many layers. The more outer one will be the first one to solidify when in contact with a lower T° than it’s fuse T°. That layer will slowly transfer that lower T° to the next one and so on until completely solidified.

So if you want a clear & precise marking, your technique of preheat is very nice !
though, if you want your product to keep it’s marking, i guess it should cool down & solidify IN the heated mould (which would imply more time &/or more moulds & compression systems if you want to produce more faster)

(i have myself only tried 2 ways,
– mould in oven with plastic inside to melt and unmoulding was a REAL problem;
-putting in “cold” mould: indeed you can see the shrinking of the plastic, but i find it cool, it makes a brain-map-like pattern :p))

cheers !

warrior
23/01/2019 at 09:26
3

my advice : don’t heat your mould 😀 it will come out perfect :p
Just be care to not put PE or PP above 200°C and PS above 250°C  cuz then thermodegradation will start operating (PS starts melting at 160°C) !

cheers!

(ps : thanks @jegor for pointing me out errors on temp values)

warrior
19/01/2019 at 18:47
0

Bonjour Henna !

Sans vouloir dire que telle ou telle chose est bien ou pas bien.. s’amuser à rajouter des additifs dans tes plastiques ne serait pas conseillé…

 

Le but ici est de recycler du plastique non ? Plus il y aura d’additifs et plus le recyclage derrière se verra difficile /impossible

De plus.. mélanger “tous les plastiques” qu’ils trouvent…y’a pas pire comme démarche.. s’il font vraiment ça… j’donne pas longue vie à leurs produits

peace !

warrior
18/01/2019 at 21:39
0

awesome document ! thanks for sharing !

warrior
18/01/2019 at 21:12
1

Hey Joseph !

Very nice document you started there!
Another type of tax which should be emphasized is concerning the salaries (ie. in France, it is very high; approx 25% added to the net salary if you are an employee & 50% if you are an employer)
Also, a good example in your spreadsheet (in red) for the costs could be the moulds ! They can be quite expensive depending on how you make them !

Last but not least :p There is also a lot of R&D & experimenting time needed to perfect the different techniques & discover new ones ! People shouldn’t neglect that part when preparing their PP project !

Hope the document will help a lot of people into officially starting a Precious Plastic Project !

Peace!

Viewing 30 replies - 31 through 60 (of 204 total)