Week 14 — Group assignment: Molding and casting

Group assignment

Guangzhou (Chaihuo) — group documentation: comparing molding and casting materials, safety practices, and process workflows.

For Week 14, we followed the group assignment materials and focused on what we learned from the comparison process: how to read material behavior, how to work safely, and how to choose a process that is realistic for our own project timeline. Instead of treating molding and casting as a single technique, we started to understand it as a workflow that includes material selection, preparation, mixing, curing, and evaluation. That helped us see why even simple casting results can vary a lot depending on small decisions made at the beginning.

Note: The photos below are from the Chaihuo Week 14 group documentation page (shared team material), not individually shot by me in this page. I used them here as visual references to summarize the group observations and to record the main lessons that are most useful for my own future work.

1) Silicone comparison: we learned to choose by behavior, not only by price

The two silicone options (HongDa and ShinBon) taught us that small differences in viscosity and curing profile can strongly affect mold quality, bubble trapping, and demolding convenience. Our key takeaway: always run a small test cast before committing to a final mold. A material that looks cheaper or more convenient at first may actually create more rework if it traps bubbles easily or cures in a way that makes the mold harder to release. This comparison reminded us that material choice should be connected to the shape, detail level, and expected finish of the final part.

2) Safety practice: PPE is part of the process, not optional

The group examples made one point very clear: material handling discipline matters more than speed. Silicone and AB resin can irritate skin/eyes and produce harmful fumes in poor ventilation. We learned to treat PPE, ventilation, and cleanup as mandatory setup steps before mixing. In other words, safety is not something to remember only when a problem appears; it has to be built into the workflow from the start. Preparing gloves, masks, mixing tools, and waste handling in advance also makes the whole process more stable and less stressful.

3) AB glue casting: process control is the main skill

From the AB glue section, we learned that casting quality depends on repeatable process control: consistent ratio, complete mixing, and stable curing conditions. This is directly useful for future composite parts and transparent/rigid cast components. If the ratio is inaccurate or the mixing is rushed, the result can stay sticky, cure unevenly, or contain visible defects. This part of the assignment helped me understand that successful casting is less about one "correct" material and more about building a careful, repeatable method that can be trusted.

4) Personal takeaway for future assignments

For me, the most valuable outcome of this week was not only learning the names of the materials, but also learning how to think before starting. I now have a clearer idea of what questions to ask first: What kind of geometry am I casting? How much detail is needed? Is flexibility or rigidity more important? What failures are most likely, and how can I reduce them before mixing anything? This mindset will be helpful in later assignments and also in my final project if I need custom soft or rigid parts.

• Always do a small pilot cast before final geometry.
• Choose material by viscosity/curing behavior for the target shape.
• Write safety checks into the procedure (PPE, ventilation, disposal).
• Log ratio, timing, and ambient conditions for reproducibility.

Source

Group template and media source: Week 14 — Group Assignment: Molding and Casting.