6. 3D Scanning and printing¶
This week I tested different 3D printing technologies (FDM & SLS). Also, I improved my skills in 3D scanning.
3D Printing¶
In this section, I’ll go through the group and individual 3D printing assignments I did this week.
Group Assignment¶
The group assignment was to test the 3D printers we have at our lab, and to investigate their limitations. We used an SLA and an FDM to complete to complete this task.
FDM¶
The printer we used is an Original Prusa i3 MK3S+.
Test 1¶
We first did the all in one 3D printing test which consists of the following: - Overhang test - Bridging test - Holes test
Before printing, there were a couple of steps that we needed to go through. We first downloaded the file from Thingiverse. Then, we imported the file to Ultimaker Cura. Afterwards, we chose the printing settings to be: Infill = 40%, Layer height = 0.2 mm, Adhesion & Supports are off. After slicing, it was shown that the model required 46g of filament and almost 5 hours of printing.
After printing, the model looked as shown below. Noticeably, printing at angles over 45 degrees resulted in stringing. Stringing was also very clear in +10mm bridges.
Test 2¶
The second test we did is the Customizable 3D Tolerance Test which
Before printing, we did the following: 1. We first downloaded the file from Thingiverse. 2. Then, we imported the file to Ultimaker Cura. 3. Afterwards, we chose the printing settings to be: Infill = 40%, Layer height = 0.2 mm, Adhesion & Supports are off. 4. After slicing, it was shown that the model required 26g of filament and almost 3 hours of printing.
After printing, the model looked as depicted below. Noticeably, a clearance of 0.3mm is the minimum for printing in place using a Prusa.
SLA¶
The printer we used is a Form 3B+.
Tolerance Test¶
We conducted a tolerance test using the SLA printer. We followed the following steps:
- We designed an XYZ calibration cube.
- We used the CAM software to make the cube’s edge length = 30 mm.
- We applied supports via the command: Auto Generate Support.
- After the cube was printed, We measured its edge and it happened to be 30.12 mm. This implied that the tolerance equaled 0.12 mm.
Individual Assignment¶
For the individual task, I designed and 3D printed a simple omni-wheel that I will use in a future robotics project. The wheel consists of two male and female parts. The idea behind the design is to have a roller always touching the ground to ensure the wheel can move in horizontally at time.
As illustrated in the video below, I started by modelling the first part of the wheel. I first made a 2D sketch for the part and designed six placed where rollers will be. Then, after extruding it, I designed six shafts around which the rollers will rotate. Finally, I designed the rollers and moved them into place. The next step was making a copy of the part, and adding male and female parts for each of them.
Afterwards, I moved to Ultimaker Cura to slice the model. I used an infill of 50% because the rollers I used are small and I want them to endure the stress. Moreover, I used a layer height of 0.2 mm which is good for this kind of model. I turned adhesion off because the surface area is large. Finally, I turned supports on (but limited to be touching build plate).
Hero Shot¶
Files¶
- Female part: Stl[Fusion360]
- Male part: Stl[Fusion360]
3D Scanning¶
The 3D Scanner we have at our lab is 3D Sense
I decided to use the scanner to 3D scan my self. So, I fixed the scanner to the table, and brought a rotating chair.
As depicted below, the process started by choosing the nature of the object I wanted to 3D scan. I chose person. Then, I chose to scan my head only. Afterwards, I asked a friend to press start on the software to start scanning. I started rotating slowly until I finished a full rotation so I asked my friend to press stop. I had to redo the scan multiple times because the scanner had difficult time capturing the details of my hair. Finally, I saved the file in STL format.
