As part of the group work, we learned how to use CNC machine and how dangerous it can be. Make sure to tie your hair and don't wear too-long sleeves when using the machines.
In order to create this smooth process, we should first design the mold on CAD and export into grbl file.
Once upload them on Genmitsu with SD card, now prepare for the machine!
We learned to first set the X and Y axis, then move X & Y to different side to set your Z axis. We used paper to make sure the milling cutter 'bites'.
Since OOMMOO is not safe to touch with hands, we wore gloves when mixing the mixture.
Mixing these materials also releases gases that can be harmful if inhaled. To stay safe, I maintained a safe distance during mixing and worked in a well-ventilated area.
When working with casting materials, precision is very important to create hard, well-cured outcome. The components must be mixed in an exact 1A:1B ratio to ensure the final mold has the desired texture and durability.
Two important terms to keep in mind during casting are pot life and cure time. Pot life refers to the time available to mix, pour, and work with the material before it begins to set, which for our materials is about 8.5 minutes. Cure time is the period required for the cast to fully harden and be ready for use, approximately 2 hours. During the pot life, we focused on removing air bubbles and carefully filling the mold to avoid imperfections.
From Marcello, we also received some tips on making the bubbles to get away. We can either use a vibration plate to remove bubbles, use vacuum to remove bubbles to reduce porosity, or use lighter to get off some bubbles in the parts.
Individual - Molding & Casting
For my first iteration, my design ended up to be less smooth during second pass, and end up causing a mess on the milling cutter. I was able to debug this and find out that it was because I was trying to cut too much and too steep with small cutter on the second pass. And this is also because for my first pass cutter couldn't do a lot of work as my design was too narrow for it to pass.
I fixed this for my second iteration.
From my personal experience, I found that using a vacuum chamber can be time-consuming and difficult to manage, as small bubbles kept forming, and I ended up waiting too long, resulting in the mixture hardening prematurely. For a faster and more reliable process, I recommend placing the container on a vibration plate during mixing and then using a flame to remove surface bubbles after pouring.
When adding color to the mixture, I learned that it’s best to mix the color into one component thoroughly before combining it with the other. This approach ensures a uniform and vibrant color throughout the cast without streaks or inconsistencies. By following these steps and incorporating Marcello's tips, I was able to achieve better results with minimal imperfections.
