Construction Of Plastic Waste Extruding Machine To Produce Filaments Of 3D Printing Machine

This paper presents design and development of plastic waste extruding machine to provide 3D printing laments. The motivation of this research is to create a 3d printer lament from plastic waste using simple machine components. In addition, another goal is to create valuable items from plastic waste. The research process begins with design, needs analysis, machine rebuilding and electrical assembly, machine function testing, analysis of lament, and lament testing in 3D printing machine. The categories of shredded plastic material were plastic cups (polypropylene, PP) and a mixture of plastic bottles (polyethylene terepththalate, PET) and plastic cups (polypropylene, PP). The analysis of the research was the capacity of the extrusion machine, the best temperature in producing laments based on shapes and sizes, and testing of 3D printing laments of plastic waste which was applied to the 3D printing machine. The result showed that 190°C was the greater temperature to heat the barrel, machine capacity of each plastic waste category, and the characteristic plastic waste was almost similar compared to market lament of polylactic acid (PLA) in terms of lament size and 3D printing machine parameter.


Introduction
The technology being currently developed is the 3D printing machine. In the world of mechanical engineering applications, 3D printing machines are very useful for research and development because they can make complex components in the manufacturing process. Apart from that, 3D printing also offers other bene ts such as; easy to manufacture because it only relies on drawings or so-called Computer-Aided Design (CAD), and also produces products with high precision [1]. Because of the advantages of the 3D printing machine, so many industries have started a business to manufacture components from 3D printing machines and applied their machines to create products simply [2].
Plastics are currently one of the environmental issues that every country in the world cares about. The source of the negative effects of plastic is the toxicity available in the plastic itself [3]. This effect will certainly affect the condition of the environment, humans, and marine life. Based on a research report written by the College of Engineering, University of Georgia, USA, that around 275 million tons of plastic waste were generated in 192 coastal countries in 2010, of which 4.8 to 12.7 million tons of plastic waste entered the oceans [4]. From this research, Indonesia is the second-largest country after China which produces plastic waste. According to data compiled by The Ocean Cleanup Foundation, The Netherlands, plastic waste spreads to the oceans through rivers of around 1.15 to 2.41 million tons annually [5]. In fact, the water pollution became a big issue due to bad sanitation that could affect the health risk to the people [6].
Until now the handling of plastic waste has not been paid much attention to several manufacturing industries in producing goods because the manufacturing industry players do not place the main focus on environmental issues. In addition, some industries only use plastic as a material in production without thinking about recycling it into new products. This resulted in the absence of handling plastic waste from the industry itself, even though the level of plastic waste produced in the world continued to increase to around 381 million tons in 2015 [7].
To reduce plastic waste, researchers began to innovate through plastic waste extrusion machines.
Bhavesh Variya et al. Has designed a plastic extrusion machine that will be used to recycle plastic [8]. The core process in extruding plastics is heating the plastic. The temperature when heating the plastic can be adjusted based on the sensor used in the engine. Jialin Xu et al. studied the temperature regulation of plastic extrusion heaters based on simulations [9]. 3D printing machines also became popular in society.
Because the process to create 3D printing machines was relatively easy, some tried to manufacture the machine personally [10]- [11].
The common material of 3D printer machines is from plastic such as polyactic acid (PLA), acetonitrile butadiene styrene (ABS), high impact polystrene (HIPS) dan polyvinyl alcohol (PVA). On the contrary, V.
Miron studied lament of 3D printers with materials of tailor which was considered satisfaction to be applied in 3D printing machines [12]. Recycled plastic of polyethylene terephthalate (PET) had also been researched by Mark Exconde. By redesigning the breadboard to the light lamp, PET material as sources of lament could be formed to be breadboard using a 3D printer machine [13].
However, the research of extruding machines studying the construction of machines only focused on producing laments. This paper studies that the extruding machine produces lament for 3D printing machines. Furthermore, the 3D printing lament created concerns about the size of its lament in order to have the average of its diameter. The purpose is that good lament from plastic waste can be applied in 3D printing machines with categories of nozzles in the machines. In addition, the capacity of extruding machine to produce 3D printing lament was measured. The way to produce its lament is to reconstruction the extruding machine to be autonomous in operation.

Methodology Of Mechanical Design
To get the ideal condition of machine, rst step of reconstruction is to consider the design of machines.
The machine was designed by using CAD software. Several considerations to produce the lament of 3D printing machines through the extruding machine are (1) the size of lament should be in average, (2) the structure does not contain any bubble inside, and (3) the result of lament is not burnt.
The rst generation of extruding machine only focused on recycling plastic waste of polyethylene. The main process of machine was heating the barrel in which the small pieces of plastic were ready to be burnt. The analysis of the previous machine was the barrel temperature to heat the plastic, lament size, and surface roughness of lament. From those analysis, the lament with 190°C was the best temperature to produce lament based on solid size from the average diameter and surface roughness test [14].
The components of the previous extruding machine were (1) frame, (2) reducer, (3) motor, (4) hopper, (5) nozzle screw, (6) band heater, (7) barrel set, (8) bearing, (9) pulley and belt transmission, (10) electrical box, and (11) thermostat. Steel is the material used for barrels. Screws are paired up inside the barrel to push the plastic out. The nozzle is a component that molds the extruded plastic after the plastic has been heated. The nozzle circle is 4 mm in diameter, which means the solid lament result should be about 4 mm in diameter.
It is different with lament used in 3D printing machine. The innovation has been applied to mold laments for 3D printing machine. Three plastic boxes function to place the shredded plastic with each kind of plastic. In addition, the fan is available to freeze result of laments after heating. This process is important to get the same diameter of lament before being rolled. The last innovation is automatic lament roller machine to entwine the lament. Complete components of the machines are (a) frame, (b) plastic boxes, (c) hopper, (d) motor AC, (e) reducer, (f) barrel, (g) fan, (h) ready-to be lled roller, (i) lament roller, (j) pneumatic, and (k) electronic box. Figure 2 shows designs of barrel set to heat the plastic. At the end of barrel, there is a nozzle to mold the lament into size of 1.75 mm and 3 mm. The size was determined as original laments produced in industry were those sizes. The matric drag is available on nozzles to replace easily. Lead screw has function to push the heated plastic into nozzle. The length and diameter of lead screw have been measured to get the ideal volume of heated plastic.

Mechanical Construction
The assembly process of each component applied the SMAW welding method and the bolt-nut method. The rst component to be assembled was the barrel welded to the stand. The barrel holder was made a hole to connect the barrel and its holder to the frame. After that, install the screw in the barrel. The process of joining components to the frame also used the bolt-nut method. Some of the components that were combined were the barrel and holder, bearings, electric motor and gearbox. After placing the components on the frame, the pulley was installed on the electric motor, gearbox and on the screw shaft.
Then do the belt installation by paying attention to the alignment of the pulley side.

Electronic and Control Machine
The automation system in this study was divided into 2 types, namely the extrusion process and the extruded lament handling process. In the extrusion process, the controlled components were three servo motors, AC motors, 16x2 LCD, 2 ch relays, and 3 heaters. The main control is the Arduino uno AT Mega 2560. Then the input used is the thermocouple and bluetooth HC-05 module which would be connected to the MIT APP inventor. Whereas in the lament handling process, the components used were servo motors, 2 5/2 valves, a 250mm cylinder, a DC motor, and a 220V relay. The main control for controlling was the Arduino uno AT Mega 2560 and the input used is an infrared sensor and a push button connected to a relay.
The MIT Inventor application served to create an android-based control system. The application was developed by the Massachusetts Institute of Technology and can be accessed via the web. The application design featured an extruder motor button, a bluethooth connection button, a set time, a reset time, a display delay time, a temperature set, a heater temperature reading, and a plastic chopping valve button. To connect the android application with the microcontroller, the HC-05 bluetooth module was used. The function of the HC-05 bluetooth was to send serial information to the microcontroller.

Experimental Test
To nd out the best temperature for extruding plastic waste in chopped shape, testing was necessary. The data collection process was carried out on two types of plastic as a material, namely chopped plastic cups (polypropylene) and a mixture of chopped plastic bottles and plastic cups (polyethylene terepththalate and polypropylene). Each type of plastic was stored separately in a shredded storage box. Some of the tools used in data collection were; extrusion machine with 3 mm nozzle, stopwatch, 5 kg digital scale, and digital varnier caliper.
The process of extrusion started from the preparation of shredded plastic which put in a separate box.
The shredded plastic entered to barrel through hopper. The lament would be formed by nozzle and be frozen by 2 DC fans. To get the ideal of motor speed, the researchers have been studied to do trial and error on machine. In result, the speed of motor to drive lament was 72 RPM and the speed of motor to roll the lament was 54 RPM. The tests have been carried out many times to get the best parameter of barrel temperature. However, the extrusion test for the shredded plastic bottles of the polyethylene terepththalate did not come out of the nozzle. This was because the type of material and the thickness of the plastic in the plastic bottle were different. So that in the plastic bottle extrusion test, it is necessary to combine it with polypropylene plastic cups. The greatest combination between both was 80% of polypropylene and 20% of polyethylene terepththalate. In addition, polypropylene plastic cup could become solid lament in some temperature of barrel.
In Fig. 6, it can be seen the comparison of the extrusion of plastic glass in the form of laments. Experiments were carried out by comparing the temperature of the barrel in melting the plastic, from a temperature of 150°C to 220°C. From the visual, the temperature of 190°C had a perfect lament shape. This was different from the temperature of 150°C to 180°C, which had white spots which indicated that the plastic was not completely melted. However, for extruded laments a temperature of 200°C to 220°C had a non-straight structure as well as 190°C.
In Table 1, It appears that the data from the extrusion of polypropyleneplastic plastic cups with temperature variations. Any temperature set from 150°C to 220°C could melt shredded plastic cups. The fastest extrusion time was 220°C and the longest was 150°C. In data collection, the weight of the extruded plastic glass was also calculated. From this data, a benchmark for how much chopped plastic cup was needed when extruding can be taken.  Table 2 shows the diameter size of the extruded plastic glass of polypropylene. The size of the nozzle was 3 mm. so that the extruded product should not be more than 3 mm and less than 2.5 mm. The process of measuring laments used a digital varnier caliper with a Mitutoyo brand with a tolerance of 0.05mm. This measuring tool was used in order to get an accurate value. The measurement results showed that temperatures of 160°C, 170°C, 180°C and 190°C had a lament diameter of 2.5mm to 3mm, while the temperature of 150°C had a lament diameter of 3.73mm which exceeded the diameter of the nozzle. In addition, 200°C, 210°C, and 220°C had lament sizes which were considerably less than the size of the nozzle.
In Fig. 7, it appears the comparison of the extrusion results from the comparison between polyethylene terepththalate plastic bottles and polypropylene plastic cups in the form of laments. The combination ratio was 80% polypropylene plastic cups and 20% polyethylene terepththalate plastic bottles. This test was carried out by comparing the hot temperature of the barrel in melting the shredded plastic, which was from a temperature of 150°C to 220°C. From the visual, the temperature of 190°C had a lament shape that was more perfect than the other laments. However, for temperatures of 150°C, 160°C, and 220°C, there was no lament at all. This was different from the temperature of 170°C and 180°C, which had an irregular shape which indicated that the plastic was not completely melted. However, for extruded laments, the temperature of 200°C and 210°C had a non-straight structure as well as 190°C.   Table 3, it can be seen the data from the extrusion of mixing between polyethylene terepththalate plastic bottles and polypropylene plastic cups with temperature variation settings. From a temperature set from 170°C to 210°C it can melt the chopped plastic. However, for a temperature of 220°C, it is too liquid to produce an unsustainable melt. Meanwhile, 150°C and 160°C did not produce plastic melt at all. In data collection, the weight of the extruded plastic was also calculated. From this data, a standard for how much chopped plastic was needed when extruding can be taken.
In Table 4, it can be seen that the diameter size of the extrusion of between polyethylene terepththalate plastic bottles and polypropylene plastic cups is combined. The size of the nozzle was 3 mm. so that the extruded product should not be more than 3 mm and less than 2.5 mm. The process of measuring laments used a digital varnier caliper with a Mitutoyo brand with a tolerance of 0.05mm. This measuring tool was used in order to get an accurate value. The measurement results showed that a temperature of 170 to 210°C had a lament diameter of 2.5mm to 3mm. However, temperatures of 170°C and 180°C had a diameter of more than 3 mm. In addition, for a temperature of 220°C there was a part of the lament diameter that was below 2.5 mm. This made the surface of the lament less at. Unlike the case with temperatures of 190°C and 200°C which had a diameter range of 2.5 mm to 3 mm. In general, there are two types of 3D printing lament sizes, 3 mm and 1.75 mm in size. However, the average 3D printing service entrepreneur has a machine with a choice of 1.75 mm laments. So that in the production of plastic waste laments in the extrusion machine using a nozzle that produces a lament size of 1.75 mm. Based on previous data collection, the extrusion temperature in the machine for producing laments was 190°C. The motor speed was 72 RPM and the roll motor speed was 54 RPM. Testing of extrusion machines by producing plastic waste laments has been carried out. The weight of plastic waste tested starts from 50 grams, 100 grams and 150 grams. From this test, 3D printing laments were obtained from plastic waste that was tested on a 3D printer machine. Seen in Fig. 8 (a) and (b), the extrusion laments were from plastic waste. From the visual, it can be seen that the PP lament had a brighter color than the PET and PP mixed lament, which is pale in color. Apart from that, PP laments also had ne surface roughness, whereas mixed PET and PP laments were very coarse.
From the machine function test, it can be seen the capacity of the extrusion machine in extruding plastic waste. It is found in Table 5 that the machine capacity in extruding polypropylene plastic glass (PP) to produce 3D printing laments is 83.11 grams/hour. In contrary, the machine capacity for extruding the combined PET and PP plastic was 179.84 grams/hour. So that it can be seen that the combined lament has a higher and faster production capacity. This is because PET plastic is too liquid when extruded. Printing in 3D Printing Machine In this research, to determine the success of the plastic waste lament produced, it is necessary to experiment with printing several designs on a 3D printer machine. From this experiment, plastic waste laments will be compared with market-type PLA laments. To get the correct 3D printing parameters for plastic waste laments, trial and error was carried out on several parameters. Among these parameters are hot end temperature, machine table temperature, ller percentage, printing speed, and nozzle size. Meanwhile, PLA laments already have standard parameters according to the buyer's instructions for use.
From the experiments conducted to print designs from plastic waste laments, it was found that the best 3D printing parameters for plastic waste laments, both types of PP and a combination of PET and PP, are in Table 6. Size of nozzel 1 mm 0,4 mm Figure 9 shows the printout on a 3D printing machine using PLA laments and plastic waste laments both PP and mixed PET-PP. The print parameters on the machine use the parameters according to Table  6. There are three images that were tested for printing. In terms of the dimensions of the printouts, plastic waste laments were not much different from PLA laments. Apart from that, from the visual results of the printouts, plastic waste laments can be as thin as PLA laments. Nonetheless, the color of the PP plastic waste lament is uneven. This is due to a mixture of plastic glass waste types. Meanwhile, the combined PET and PP laments have an even color, that is, the color tends to be white.

Conclusions
This paper explored the plastic waste extruding machine to manufacture laments from polyethylene terepththalate plastic bottles and polypropylene plastic cups. The lament criteria of pure polypropylene plastic cups and mixed polyethylene terepththalate plastic bottles and polypropylene plastic cups were taken into account to distinguish with market lament of PLA. The following statement can be taken as outcomes of this research: 1. The best temperature to mold the plastic waste was 190°C not only for polypropylene plastic cups but also combined polyethylene terepththalate plastic bottles and polypropylene plastic cups. 2. 3D printing laments made from plastic waste have been produced using extrusion machines. The types of plastic waste that can be produced are pure polypropylene plastic cups with a production capacity of 83.11 grams/hour and combined plastic waste between polyethylene terepththalate plastic bottles and polypropylene plastic cups with a production capacity of 179.84 grams/hour. 3. The characteristics of the plastic waste lament produced are almost in accordance with the market 3D printing lament of PLA. Some of the suits include; the size of the plastic waste lament is 1.75 mm ± 0.25 mm in diameter, the polypropylene lament and the combined polypropylene and polyethylene terepththalate lament can be used in a 3D printing machine, and the printed results of the plastic waste lament have no defects.