5. 3D printing and scanning¶
This week I tried using 3D printers to create three dimensional objects as also as scanning objects to make digital 3D models of them.
Introduction¶
3D printing or additive manufacturing is the construction of a three-dimensional object from a CAD model or a digital 3D model. A 3D printer essentially works by extruding molten plastic through a tiny nozzle that it moves around precisely under computer control. It prints one layer, waits for it to dry, and then prints the next layer on top.
Image source
Group assignment¶
Our group assignment was about exploring 3D printers, how they work and what are their abilities. we were also exposed to samples made by the 3D printer. In addition to that we printed our first 3D printed model as shown in the below picture. Settings like infill, raft and support were explored during this assignment
From testing the 3D printer I learned the different components from which the printers are made of as in the above picture, the limited materials that are used to melt and create the objects like FDM, PLA and SLA, Some of the limitations such as the size of the printed object and the time the machine takes for the printing. Also the printer can not print relatively small objects or parts that are floating without stands.
The 3D printer is capable of making objects with shapes that can not be done with other subtractive methods as other techniques can’t reach some angels shown in the picture bellow in addition to creating interior details inside covered surfaces. we used MakerBot Z18 3D printer from makerbot company this printer can print relatively big size objects and has an excellent heat insulation.
For a 3D object to get printed by the 3D printed the mesh or surface of the 3D model must be watertight and a solid. All the surfaces of the object must construct one or more closed volume entities. When the faces are not fully closed, they produce gaps or holes in the model and those holes and gaps will keep the model from printing correctly as they affect the quality of the printed model. perform a geometry check of the STL files before continuing. Thirdparty software for this purpose attempts to fix the geometry of problematic files.
More details are available on Behnaz’s page.
Indivisual assignment¶
In this assignment we were tasked to print our own models using the 3D printer.
3D design¶
A simple 3D model for Saturn was made using Fusion 360. Later are the steps for the design:
1) The sphere shape for the planet
2) Adding the Torus for the planet ring
3) creating pipes to connect the two bodies
Click Here to download the stl file
Click Here to download the CAD file
3D printing¶
In this assignment I used MakerBot Z18 3D printer
The desired models are added to the plate to get printed all together to save time.
The printing output
The printed planet had a sphereical shape with round surface and details that are not possible to be made by subtractive methods. The shadded half of the model shown in the above picture is not possible to be made in other method than 3D printing as it requires more than three axes.
3D scanning¶
3D scanning is the process of analyzing a real-world object or environment to collect data on its shape and possibly its appearance. It is the opposite process to 3D printing. Different machines and methods exist to 3D scan objects like Laser 3D scanning,Photogrammetry and Structured Light Scanning
“Next I present the result of 3D scanning on four phone applications “
Qlone 3D scanner
This application needs a reference surface to sit the scanned object on as shown in the pictures bellow
multiple pictures of the object were scanned from different angels
The scanning output
The application managed to capture and reform a close but yet full of distrrtion 3D model of the scanned object as the chosen Luigi lego model had alot of details.
Polycam
No refence surface is required in this application. I secided to scan the same 3D cat model printed in oir group assignment.
156 images were taken to construct the cat model
This is the output of the scanning. An almost perfect representation for the front of the cat but a poor result at the back. one possible reason for thais is that I was supposed to take more images from that side.
Download the GLB file from this link
According to the criterias mentioned above the scanning output of the two applications are 3D printable.
KIRI Engine
The third application I used was kIRI. It requires a plane background to get accurate results
I scanned this sloth toy
The output came out to be acceptable with some distortion in the body
Click on this link to veiw the scanning result
WIDAR
WIDAR is a basic 3D scanning application. The process of scanning was easy and the results were hummble
I tried scanning this plant model
This is the final result of the scanning
Download the STL file from this link
The last two scanning outputs contained some floatings and not fully closed surfaces so they need processing before they can be printed with the 3D printer.
Some of the general notes when using phone applications for proper scanning is that it requires a plane background, a strong lightening, taking enough frames (pictures) from every angel and that the quality of the scanning is dependent on the details of the object.
All of the four scanned objects came out to be distored, so they need to be processed before getting them 3D printed. Even after that the output will not perfectly reflect how the original object exactly look.