02

First, we would need a 3D model. Popular platforms, such as Thingiverse, has a wide range of designs and free models for test printing. For beginners like myself, test cubes are usually recommended for initial prints due to their straightforward geometry and lack of need for supports. Models are typically provided in the STL format, the most widely supported file type for 3D printing software.

Once the STL file of the 3D model is ready, we can move on to slicing, which is converting a 3D model into a series of layers that the printer can read. This will generate a G-Code file, which contains the detailed instructions for the printer to produce the object. While the G-Code itself may appear complex, a detailed understanding is generally unnecessary for most users.

There are various slicing software options available. I will be using Cura, which is widely regarded as a versatile choice, with a beginner-friendly "Recommended Mode" that simplifies the setup depending on the model of the printer by providing the essential settings like layer height, infill percentage, support structures, and adhesion. Its compatible with most printers and has an extensive community.

Once a model has been sliced and the G-Code file generated, it is transferred to the printer, typically using a flash drive or SD card. The printer uses this file to guide the printing process. Calibration of the printer prior to printing is important for accuracy and quality, and this is often achieved using standard calibration procedures.

I finally received my filament for the 3d printer. I chose grey PLA as the filament colour for this project. Based on my research, monochrome colours are typically preferred for test prints and prototypes because they make it easier to observe fine details.

Grey, in particular, provides excellent contrast without being too reflective (like white) or obscuring details in shadows (like black). While I plan to purchase other colours for future projects, grey was the most practical choice for evaluating the printer’s performance.

For my test print, I downloaded an STL file of a test cube, which includes alphabets on its surfaces to evaluate how well the printer captures fine details. Link: https://www.thingiverse.com/thing:1278865.

For slicing, I selected Cura as the software. Although Cura didn’t have my specific 3D printer model (T3) listed, I found that the Ender 3 Pro shared similar settings and chose it as a reference.

After researching potential causes, I discovered that bed leveling and the Z-axis nozzle position are the most common culprits for poor adhesion. Since the printer I purchased has an auto-leveling feature, I enabled it for this test print. For the Z-axis adjustment, I learned that I needed to modify the printer's software settings to disable certain safety measures that were preventing the nozzle from moving closer to the bed.

Instead of updating the software immediately, I decided to manually adjust the nozzle height based on my judgement. I also enabled adhesion settings in teh slicing software to ensure the filament would stick properly to the bed and selected support settings as needed for the test print.

I found a case for the Arduino on Thingiverse and decided to use it as a reference point to check the dimensions for my future interface. The print turned out well overall. The surface was slightly rough, but the bottom part—where the adhesive was applied—was much smoother.

Later, I experimented with 3D modelling for display casings. For the 3.5-inch display casing, I used the Arduino case as a reference for the Arduino section at the bottom, which connects directly to the display.

For the 6x2 LCD display casing, I modelled it myself but relied heavily on an existing Thingiverse model for the size. The LCD display required additional considerations because of the protruding part on its back, which I accounted for in the design.