Forum Replies Created
s2019 is fully right!!!
The list of injection molding machines and extruders here above is for manufacturing equipment (If you do not take it personally, I’m going to provide a fix to it as there are some mistakes and a lot is missing)
in our case however, we are in the world of recycling, a nochr of recycling I would say…
the need is a bit different…
there are some dedicated machines for this purpose.
i must also add that recycling could mean 3 things:
– different way to use the equipment (most of time, machines are exposed to brutal use and machines for this purpose, may be over robust, but not necessarely because other criterias, see below, may take prefominance).
– different process (recycling is an integration of functions and most of the times it needs selection, washing, etc. machines for recycling may integrate extra functions)
– price (be aware…. saving money may be VERY DANGEROUS, you may end up with HEAVY chunks of useless metal crap…)
for those who needs it I know People here and there selling machines they do not need anymore for few k€…
they work and I think they can even show them working, they may need some work around, but are industrial grade…
feel free to contact me if you need something like the attached…
The same contacts are valid also for extruders.
check in with them and if you do not find what you are looking for, get back to me, we will figure out how to make it happend.
feel free to give me some “numbers”
Ciao Andyn, thanks also to you!
I agree, it’s a critical point.
You cannot do it on a lathe, but rather a cylindrical grinding machine.
In my area are pretty easy to find, but not sure this is true everywhere and that’s why I suggested the option of doing the operation using a tube as a guide.
You do not like it?
good luck, nice project! 🙂
while waiting fir some more competent contributions on the topic, here a fee notes.
useful link, even if you probably have it already:
you can mix sand, but I do not think it will do a great job as other additives like Aluminium or magnesium hydroxide, phosphorous, etc.
i have to check better but I think that some natural carbonates may do the job as they would produce CO2 during thermal degradation diluting combustion gas and extinguishing fire.
What I have to check is the degradation temperature, because if it is lower than processing temperature,they will simply foam up your material while processing, useful if your target is to make it soft or to reduce density, but not as a flame retardant.
however, for replying to your question, yes, you can add sand and yes, it will damage your equipment as it is thin, but harder than many metals. Which “sand” do you have in mind?
some coral sand may work, maybe shells’ sand, etc.
does this help a bit…?
absolutely true, but in some cases, imagine for example the lost-wax technique, the mold is for a single use…. in some cases it’s worth… 🙂
Beside that, the mould can be smoothened with a grinding tool.
another option is to use a torch, the torch glasify the surface and makes it glossy smooth…
We can try…
let’s call for a challenge on that 🙂
Thanks for the reply Olivier!
You are right about straightness.
And thanks for bringing this up!
ok, the process could be done inside a tube that keeps it straight… 🙂
where exactely are you located?
let’s meet maybe!
Mmmm… my feeling is that you guys love eachother soooo much that you end up being like husband and wife… 😄
I’m in, but no facebook plz
Let it flow…
thick skin Buddy!
i did something similar to what you are doing in the last 5 years…
at a certain point I decided that it came the time to shift to the next level and that’s when I decided to reimburse a few of the team (not me) in order to give continuity.
within the team of the most valuable some understood and some didn’t.
Those which did not understand, got lost, we are still in good relationship, but they are no longer on board.
Those which understood, either they got the reimbursement or theywere too busy for guaranteeing continuity and therefore just work as volounteer tripled their efficency and allowed the structure to grow.
Balance of the project…
– we started in 5
– 30 people made themselves available as volunteers in the free time and their precious help (which I’ll never forget) allowed to create the structure in 3 months.
– 10 continued to help after the start-up for another 10-12 months
– another 4 people joined the crew and contributed to collect 30 new subscriptions contributing with 150€/yr
– when I decided to start with the v2.0 we lost 3 people from the initial team, I was very sorry, but I knew that some People cannot just understand and prefere to complain on what is being done rather that looking at the big picture and be strong and constructive. Reacting to the change they lost focuse on action
– in the next 9 months we got on board 20 new volunteers and reached more than 250 subscriptions.
– today our initiative is able to allow free access to the climbing gym to everybody, is hosting physical and social free rehab programs.
Inside myself I’m sure that everybody will understand at the end, we just have to be patient, here is easy, because is a very local initiative, it will be more difficult for you.
Keep focused on action and do not react to the noise, just smile and keep going!
Everybody can make plans and achieve targets, as far as I see it, you are borrowing your efforts to the world and I’m sure that most of people understand that those fxxxxg 300k are an award TO YOU!
You will be a Hero if you will use them for the revolution you are setting-up, but this IS NOT DUE!!! I will not blaim you if you will decide to spend them all in chocolate and icecream for yourself, but I’m sure you would never be able to do it because you understand how more valuable is for you and for the world to be a hero and a Leader, which by the way you are…
so… look ahead and stay focused on your great plan, those which cannot understand will just get lost with more or less noise, the newcomers and those which have Faith, will help you and the project in continuing till the last piece of plastic waste on the more remote beach of this wonderful world.
per aspera ad astra
the key is to act!
300k is NOTHING with a global plan to handle.
unpaid jobs is KEY if you want to build an army, unless you do it for business, then you should better pay People.
preciousplastics is not business and you see this in every corner of it, so, it should not pay people and keep the 300k for the right things, it will come, but no rush!
manage money is difficult, waste them compulsively, way too easy… especially for sensitive People like activists…
Dave has not hidden the 300k even if the award is for HIS work, HE made it happend and he has been able to build it out of his control giving us the chance to do the right thing with the little time we have here and there. HE is the founder! This is what he has been rewarded for and he invested so far more than anybody else, giving FOR FREE to everybody, even for People that are now making business out of that.
I see that they are inviting People to work, food and bed are covered! (I wish this happened 10 years ago when I could still do it, sxxt!!!)
an army is not paid, mercenaries are!
Dave & co, GO!!!!
And thanks for what you do and for taking the time to reply to People that still do not understand…
thank you, really!
and last 2 things: we all need a benchmark, a reference place that is making things while sharing how he does it, Dave and his crew is doing that.
in every country there are awards for this kind of activities, each one can apply and win its own and use it locally!
also, even if at a certain poi t Dave and its crew would decide to make a business out of all that… what would wrong in it…??? NADA! He has generated and given away something that anybody can use with the freedom to do the right thing even while doing business on it, because the heart of preciousplastics is to take away the trash from environment and this works waaaaaay better if somebody can sell the products he makes out of such trash, the resourses should come from that…
Stop reacting and just act, have your plan, money are a tool and are easy to find when you have a plan!
do you have a current-meter? Are you able to verify how polymer dependent is the consumption?
next would be to verify if the current is constant or it spikes up and down while shredding…
in case you may like to try a flyingwheel that will absorb more energy to start, but once started it may help in reducing the spike of power and reduce the overall power consumption…
Ballbearings rather than bushings…
in general, consider that the warmer the motor gets and more energy will be wasted.
sometime a more powerful motor (oversized) May consume less than a small overloaded motor…
do you have some numbers to share…?
How would you imagine to do it…?
the filament needs to be stretched with a certain “draw-down” in order to acquire tensile properties and even if you can take multiple fibres out of a spinneret, the guides on the braider has to turn and twist…
maybe you have in mind something so clever I don’t get it straight forward…? 🙂
in any case, if it’s interesting I’ll collect some material and publish it for you here in the next days/weeks, ok?
Right! At the end we are not choosing the best material of all, but how to use something that otherwise would just stay there…
maybe it could be dangerous though if blades turn too fast…
disk break are also thicker though… isn’it…?
the problem with brittle alloys is in impact right? Maybe that using a belt transmission the impact could be absorbed… make sense…?
could you please detail a bit more where do you need help…?
this document is interesting:
In general anyway, please do not “smoke plastic”… 🙂
As mentioned, there are always toxic elements in smoke, the smaller is the environment the higher the risk also with PP so, ventilation should be in place anyway.
concentration is the key word… small amounts in confined spaces can accumulate and become hazardous with any polymer.
the unavoidable CO, replaces O2 in your blood and can kill…
Open air environment or ventilated areas are safe when processing PP and PE, but this doesn’t mean you should underhestimate risks of unforeseen additives like aldeydes, etc. as Manix say here above the problem are additives that may produce traces of other organic compounds than CO and CO2.
Better sooner rather than some $’s down the road isn’it…? 🙂
I initially thought that the idea was peculier, but I thought maybe I do not know the whole story… now that I went through it once more… well… maybe I misunderstood, but… if you think to make a screw out of aluminum… well… unless you want to extrude soap at low throughput… be aware it’s not gonna work… 🙂
A casted screw would not work, aluminum even less…
If I can do it, I will be happy to do it for the cause…
if you would like to send me your drawing I can cut it half…
which extension do you need?
It depends on temperature and polymer…
Polymer processed correctely should produce nothing too bad or at least not in dangerous concentrations, BUT! It’s sufficient a broken thermocouple that causes a overheating or a misplaced thermocouple a pellet that drop on the heater bands hottest point and the polymer may burn….
PP and HDPE or LDPE are like a candle, even if they burn, nothing bad will happend…
PET, PA, ABS, PS, etc… should no be burned or at least if it happend, mask and open air…
then there are the bad guys: PU, FEP, PVC… they may generate: cyanides, dioxin, perfluoroisobutylene, hydrofluoric acid, etc…
about temperature/heat… if PVC is burned with a high temperature and a lot of heat, any toxic gas (that is typically very reactive) may dissociate completely…
so, be very careful to always perform a proper thermoregulation… i see people talking about heating with flames or maybe cleaning tools by a gas torch…. well…. I would not do that…
Silicon steel like leaf springs one is a great suggestion too because it’s hard and elastic…
if you can accept bubbles in the product and batch production, you can even use a car jack that will push the polymer inside the chamber.
another option is to use a big air piston insisting on a small shaft.
8 bars on a 100mm piston insisting on a 25mm chamber will generate 128 bars.
In case you will use a screw I see a few options like:
– a scrapyard motor from a washing machine can do the job if you feel like playing with 3 gears and 2 chains (old bicycle…?), if the washing machine motor rotate at 1-3000RPM, by 2 transmissions 10:1 you will end up at 10-30RPM
– kitchen kneading or calendering machine…?
– electric car jack…?
if you can use glass you could then use the same process used for metal.
you put a hopper on top of the feeding hole of the mould and you heat up the mould with a halogen lamp.
The transparent mould will allow infrared to melt the plastic without heating up too much the mold, so that it’s gonna be fast in cooling.
in this way the neck of the hopper will not heat up too much either and the hopper will not melt the polymer.
the column of plastic above the mold will feed polimer while air will flow out.
everything works better if you can press pellets, while applying vacuum in order to take air bubble out while tou compensate PP shrinkage also during cooling.
PP shrinks a lot and even if you do not see it from outside it will create cavities inside the part…
a good way for avoiding cavities is to disperse something like baking soda in the melt that by foaming will increase volume elasticity. This elasticity will elastically absorb tensions and reduce deformations.
if something here above is interesting, but not clear, just ask for clarifications!
C40 is the cheapest option, hardenable and about 1€/kg…
Hey Buddy! Another option could be to work on the pitch rather than reducing the flights depth (increasing the core diameter)…
– to weld a lever to the tip of the auger
– hold in a vice the tail,
– heat up the auger tip by a gas torch
– acting on the lever, twist the hot part in order to shorten the pitch at the tip of the auger