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If you have maybe enough financial resources, you can find some useful components, even whole machines or assemblied machine parts here -> https://bazar.preciousplastic.com/?category=machines
Maybe you can find some local machine builder, from PP bazar, so the delivery will be more affordable.
@s2019 I was forecasting pressure in the nozzle diameter via simple pressure calculation -> P=F/A , and i was expecting the increase of the pressure, with a decrease diameter, as this simple equation is saying.
However i checked your link, and also i checked Bernoulli equations brefly, and its quite opposite 😀 , there is dicrease of the pressure, with dicrease of the pipe diameter, when something flows inside.
Thank you for the input ! Atleast i know now, that i need to recalculate it 🙂
@pporg you are welocome, hope it will be able to open it.
Yes I saw this video as many similar to that. i didnt catch btw book recommendations.
And yes , im aware that it is a first design shot, still very raw. 🙂
@s2019 , yes your calculation is correct. Its pressure approx. 3.7 Mpa.
95 MPa, should be created pressure in smallest diameter of the nozzle, where it connects the mold runner.
Here is 3D model link , -> https://grabcad.com/library/pneumatic-injection-molding-machine-martin-vasko-1
that has lot of mistakes i know. Its just theoretical model for now, tested just in simulation. So i would very happy appreciate some improvements. @pporg
Hope it will work. I used function “Pack and go” so everything should be there 🙂
Because i think, if you design this right, it can save to of time and maybe some energy ( that you dont need to press it by human power) to make it semi-automatic.
Thats the whole idea
@s2019 I done injection simulation in Solid Works Plastics with all parameters from designed injeciton molding machine, and after all, the machine was able to create pressure in the nozzle more than 95 MPa, which is quite good, and also simulated injection of cover was done without complications.
But im sure in order to have more comfortable operation and also variety of use, it would be cool to use stronger pneumatical cylinder for this design.
I will try to upload the model somehow.
@pporg in my design, the nozzle and the mold is connected with screw connection, similar as it was originally designed by Dave for injection machine.
And yes, i was thinking a lot how to design the hopper in appropriate position for smooth inseting shredder plastic into the machine.
And yes, i think the production price for this kind of design can be squeezed into 1000 euros.
Bonus photo of the form for a keyring and also some other samples of the broaches, or it could be also keyring 🙂
Im adding pictures of my recent new experiments with the HDPE.
1. Key rign in Shape of Slovakia with hand gravir of letter to the steel form.
The form is home-made with using some basic tools
2. HDPE heart shape broach – made with steel heart shape form for cakes 🙂
And thats it
@pporg it looks quite good. Hope i will be able same or better results.
Surface of this case is caused maybe because CNC milling, or because of plastic used for the injection.
Do you know, what was the cost of the mold ?
Just a simple question for those, whi have tried this method to create blades with drilling. Is it really that cost, time effective ?
Because its requiring lot of drilling, brushing , and the precision will go down probably also.
Maybe group order of laser cutted parts like 10-15 sets at once could solve this.
With this solution a bought (thanks to Katharina from Germany, currently working on Flip Flopi project) all laser cutted parts for 130 euros (shipping incluced ) from German company to Slovakia.
Thank for your info. I hope it will be able to transmiss the power from the motor safely.
Update about the shredder.
Finally i managed to find motor, transmission, a clutch.
This is how it looks so far.
Great idea Simona !
I sended you message already. 🙂
1.Did you use the latest version of the .DWG lasercutting drawings?
1.a. I used laser-cutted parts from Katharina from Germany. It was group order cca 25 sets. So i cant tell you exactly.
2.Did the assembly gone well? Did the pieces fits well? Did you do some mechanical adjustments aftes the lasercutting?
2.a Assembly was pretty challenging. Lot of dimensions and shapes of the parts were pretty not in tolerances. So i needed to brush surfaces of all parts to make smooth assemly.
Since laser is making radiuses, not 90 degrees in corners on holes for example, i was not able to assembly many parts together, so again i needed to brush corners in order to fit into other parts as a puzzle, since whole construction i created in “puzzle” style.
I needed do use driller for making 20mm(radius) counter sink for holes for bearrings screws.
I needed to brush cylindrincal parts of shaft in order to fit into bearings. ( I ordered shaft+bearring from Czech republic, other laser-cutted parts were from Germany.)
Another problem was lenght of hexagonal part of shredder. Its not accurate at all. I needed for fix many, many small intolerances, to assemly everything smoothly, and tightly.
So we needed to find many alternative solutions for shredding box, to make final version of shredding box.
It was my case, but if you order more accurate parts, also if you order accurate dimensions of shredder and bearring, you can save lot of hours of work and fixing. But in my case it was whole 2 days of assemling only shredding box to make everything as it should be.
Shaft was little bit bigger the bearings, so this is how it looked like at the first try.
We needed to brush shredder a lot, even when the difference in dimensions was tiny.
Hi guys, thank you for these inputs. I was also very curious about fumes after melting specific types of plastic. Do you know any sources about effects, fumes, hazard of melitng HDPE(2) and PP(5).
Thank you very much, Martin
Another shots from my work/experiments.
Hello all friends of recycling and PP. Here is my work from this weekend. I was again playing with HD-PE material(bottle caps) and im quite happy with the result.
I have serious question about melting HD-PE and poisonous fumes. How do you protect yourself against these fumes. Because its very dangerous to inhale them.
Thank you, Martin, Slovakia
@malor . Hi Malor, your combination of colors on the flower-pot. Its really fresh. And toward the topic of removing part it depends on material of mold. I was using aluminium mold and thanks to quick water cooling – my plastic part shrinked, thanks to decreasing temperature, i was able to remove my part quite easily.
So i recommend you to cool your part quite enough with water for example.
thanks for sharing
Yes im using “Dvojplatnička” with possibility to regulate temperature. My temperature is about 200-220 degrees. For this month there is nothing new. Im waiting for machinery to create better and more products.
Hello, thank you very much for your info. Its still good, i mean im not in hurry with it.
Hello Katherina, i sended you mail with my order and also with my address. Im interested in combined order for 80 euros. You have already my personal informations.
Thank you a lot.
One flowerpot has 300 grams
I made this flowerpot for my friend. ( 100% HD-PE material, approximately 150 of bottle caps were used for the creation)
Look for amazing combination with Aloe Vera.
What are your thoughts about it ?