3D Objects, Optimizing 3D Prints, Sustainability

Optimizing 3D Prints- An Introduction

Introduction

Many 3D printers provide a high print resolution, suitable for developing high-fidelity prototypes from a computer aided design model. One of the most widely available printing processes is Fused Filament Fabrication (FFF) type, also known by its trademarked term, Fused Deposition Modeling (FDM) in common literature.  Intricate shapes can be printed through FDM printers such as airfoil and Moebius strips [7]. FFF prototype surfaces can be enhanced on a millimeter scale even when they have geometric textures [4]. However, it is common practice among engineers and designers to build the low-fidelity versions first, as a proof of concept. There are several low-fidelity FFF printers available in the market. They can be used with a wide range of materials. But the most frequently used materials are spools of polylactic acid (PLA) as they are less toxic [8,9,13,23]. Due to the ease in their operation, portability, and abundant materials, 3D printers are designed to have fairly good environmental features, making them practical in educational institutions [6]. However, they can be made more sustainable [11] and economical [17] through material waste reduction.

Experimental studies have showcased the properties of different materials or different colors [23] while investigating effects of individual factors on the printed object. Each study focuses on at least one parameter and one material to show its impact on the quality of the final product. Poor surface finish is often caused by tessellation of the computer aided design file and slicing processes. However, the surface roughness can be reduced by modeling a design through optimizing the parameters before fabrication [14,22,26].

Printing of the first layer is crucial, as uneven material deposition on the first layer can change the specimen height of other layers [14]. Surfaces of the printed objects, especially ones which are textured, tend to show the staircase effect, where each printed layer is distinctly visible and looks like a staircase [10]. It is an undesired side effect in low fidelity 3D printers.

Parameters such as build direction, temperature of the extruder, and layer height play a major role in showing dimensional accuracy when compared with infill pattern [3]. The quality of geometry of the product also depends on print speed and layer height [20]. The surface roughness is also affected by the wall thickness of the printed object [21]. Although part build orientation affects mechanical properties such as tensile fatigue of the PLA material [2], this study focuses on the surface quality and dimensions of the objects.

Using appropriate design rules while building prototypes can save the hassle of wasted material, time, and costs associated with them. Current design rules exist only for certain boundary conditions and does not include all types of printing processes [1]. Statistical and engineering process control can be used to detect and correct the variation in the fabrication process [15]. The cost benefits of 3D printing are industry specific. However, material costs make up to 12% of the total costs in additive manufacturing. On top of that quality assurance costs need to be considered [17].

PLA is inexpensive, but wasting it should not be encouraged. Because of poor design choices, material type, amount of infill, and several other factors, many prints fail, and many do not appear as expected by the user. In other words, they do not have good quality of print. Hence, hundreds of printed objects are discarded and can easily affect the environment, making the process less sustainable, unless properly recycled [8]. But recycling can affect the material, which could, in turn, affect the print quality made using the recycled material [8,25]. So, this study shows a way for carefully planning the 3D printing process by using the most favorable settings, to obtain the best possible results without unnecessarily wasting filaments.

Existing approaches use Analytical modeling [22], Taguchi method [3] and factorial designs [4,14,21] to determine dimensional flaws, and X-ray tomography [5,12] or scanning electron microscopy [24] to determine internal and morphological flaws. In the current investigation, the print material was chosen as PLA because it has consistently been proven to print with ease [13] and is not toxic. To reduce the waste from rejected prints, this study uses a 2k factorial design to obtain a range of optimal print settings. An X-ray tomography is also performed to determine and analyze the unevenness of the print layers and surface quality.

 

Continue reading “Optimizing 3D Prints- An Introduction”

3D Objects, Blurbs, Optimizing 3D Prints, Sustainability

Optimizing 3D Prints- Brief

Due to the plethora of things made using 3D printers, a large amount of waste is produced in the form of failed prints and wasted filaments to obtain prints of the best quality. It is important to ensure that the printing material wastage is minimal, even when it is inexpensive, for a more sustainable additive manufacturing. To keep a printed object the closest in appearance to its computer aided design, it is ideal to test the parameters that make for its surface quality. With the appropriate settings for these parameters, it is possible to reduce material waste and print failures. This paper shows that, it is possible to determine the optimal settings for different levels of infill, so that the user specifications are met. It also presents the statistical experiments performed on the printed objects of specific shapes, color and infill level, the tomographic images of the outer shell and the internal structure of their infill, to obtain the favorable configurations for optimal print quality.

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This was supposed to be a journal paper titled Determining Favorable Configurations for Low-fidelity Filament Freeform Fabrication 3D Printers to Attain Optimal Print Quality and Reduce Wastage, but I think I will post it in my blog instead.

Why? Because this is the best course of action. Enjoy my months of research which I will post occasionally.

Blurbs, Sustainability

Optimizing 3D Prints

This is going to be a new series of posts which do an elaborate research on optimizing 3D printed parts.

Why am I doing this?

Because I don’t like wasting print filament, even when it is dirt cheap… You can get 1 kilogram of poly lactic acid, perhaps the safest material to print, for as little as $20.

For something so cheap, why bother about wasting or not?

No. That’s a bad attitude. It is not sustainable to waste plastics, knowing how they are made.

I once reloaded a new filament on an ultimaker but forgot to stop the process. Do you know what happened? The hit extruder kept releasing the filament.

Well, you might say, just end the process when you see the extruder releasing the material

And I’d do exactly that. But I got caught up in another work and completely forgot about this. The bigger issue was I had kept the 3D printer on… overnight… The new filament (an entire kilogram of it) was turned into a thin string of plastic when I realized what had happened.

What a waste!

I don’t like it when waste happens for unnecessary reasons, be it food, or in this case printing material.

This series will show– mostly through technical means, but also influenced by good design practices– how to curb wasting the 3D print filament in general, by playing with the printer to get the best quality prints.