1. Shredding or buying required pellets
Pellets for PLA, ABS, TPU etc. can be purchased because it not a common plastic to find. But if you wish to use recycled plastic such as PET it has to be shredded. According to my opinion pelletized PET is more suitable for the process than shredded plastic. Because pelletized plastic pieces are equal in size and shredded plastic are not. Letting the pieces be in equal size helps the extruding process because all pieces’ heat equally. But when it comes to plastic shreds it causes heating issues in the extruding process.
Raw resins are always colourless. So it has to go through a colouring process. What we simply do is add a pigment which is made for plastic “Masterbatch” is the most used pigment additive used in plastic colouring. Since all masterbatch colouring contain a very concentrated pigment a small amount of colouring is enough to colour a large amount of pellets. The percentage of colouring is mostly around 3% respective to the weight of the pellets.
3. Drying Process
Most people used to skip this process to save time, but it is extremely important to follow this process to produce a high quality filament. The process is done by drying the coloured pellets in a container for about 2 hours at a temperature of 60-80 Celsius.
4. Filament extruder
The dried pellets are fed into the extruder and the processed filament are spooled at the end
The filament extruder
Working principle of the extruder
The main part of the extruder is a barrel with a screw which is connected to a heater at the end. On the other end the screw is connected to an electric motor. The motor transports the pellets which are inserted to the hopper. When the motor is running the pellets are pushed towards the heater and pushed out of the nozzle at the rear end.
Producing 3D Printing Filament from recycled plastic
The most common plastic is PET (Polyethylene terephthalate). Therefore, it can be collected easily without any scarcity. PET contain all the required properties for 3D printing and it is a stronger and reliable material comparing the other materials. Its melting temperature is around 220C-250C. which is an accessible temperature for an extruder.
To extrude PET as filament we have to use a shredder to break the bottle into small pieces. There is a certain point that you have to consider when shredding. Which is that you have to make sure that all the shredded pieces maintain a certain fixed size. It helps the heater to melt the shreds at a constant speed. Otherwise the extruded filament will not have a fixed diameter which leads to major issues in 3D printing.
So there it is a solution for the plastic disposing problem that most of the people worldwide are going through. Some of the countries are doing researches on table filament extruders too. Which gives the ability to make your own filament at home. So until that we as a company stands to provide the necessary solutions for your requirement.