13. Molding and Casting: Cooper, Amalia, Elle¶
Group Assignment¶
Safety Data Sheets (SDS) - Elle Hahn¶
- Review SDS for each molding and casting material.
Test Casts - Cooper Cumbus¶
- Make test casts with each material.
- Record mixing ratio, cure time, texture, and shrinkage.
Printing vs. Milling Molds - Amalia Bordoloi¶
- 3D Printing: Good for complex shapes, but slower and can have surface issues.
- Milling: Faster, smoother finish, but limited to simpler shapes.
Compare accuracy, time, material cost, and finish quality.
Saftey Sheets¶
These are the data sheets for the two casting materials we chose to compare this week.
Clear Amber¶
| Property | PMC™-746 Clear Amber |
|---|---|
| Type of Material | Urethane rubber |
| Health Hazards | May cause skin, eye, and respiratory irritation; harmful if inhaled or absorbed through skin |
| Precautions | Use nitrile or vinyl gloves, goggles, and work in a well-ventilated area |
| First Aid - Skin | Wash with soap and water immediately; remove contaminated clothing |
| First Aid - Eyes | Rinse with water for at least 15 minutes; seek medical attention |
| First Aid - Inhalation | Move to fresh air; seek medical attention if breathing is difficult |
| Flammability | Not flammable |
| Storage | Store in a cool, dry place with good ventilation |
| Disposal | Dispose of according to local hazardous waste regulations |
Smooth-Sil 940¶
| Property | Smooth-Sil 940 |
|---|---|
| Type of Material | Platinum-cure silicone rubber |
| Health Hazards | May cause skin and eye irritation |
| Precautions | Use nitrile gloves, goggles, and work in a well-ventilated space |
| First Aid - Skin | Wash skin with soap and water |
| First Aid - Eyes | Rinse eyes with water for at least 15 minutes; get medical help if irritation persists |
| First Aid - Inhalation | Move to fresh air; seek medical help if symptoms develop |
| Flammability | Not flammable |
| Storage | Store in a sealed container in a cool, dry place |
| Disposal | Dispose of according to local regulations |
Task 8 Resin¶
| Property | Task 8 Resin |
|---|---|
| Type of Material | Epoxy resin |
| Health Hazards | Harmful if inhaled or skin contact; may cause respiratory irritation |
| Precautions | Use gloves, safety goggles, and ensure good ventilation |
| First Aid - Skin | Wash thoroughly with soap and water; remove contaminated clothing |
| First Aid - Eyes | Rinse cautiously with water for 15 minutes; get medical help if irritation persists |
| First Aid - Inhalation | Move to fresh air immediately; seek medical attention if breathing difficulties occur |
| Flammability | Combustible |
| Storage | Store tightly closed in a cool, dry place away from heat sources |
| Disposal | Follow local environmental regulations |
Sorta Clear Silicone¶
| Property | Sorta-Clear Silicone |
|---|---|
| Type of Material | Silicone rubber |
| Health Hazards | May cause skin and eye irritation |
| Precautions | Use gloves, goggles, and work in a well-ventilated area |
| First Aid - Skin | Wash with soap and water |
| First Aid - Eyes | Rinse cautiously with water for several minutes; seek medical attention if irritation persists |
| First Aid - Inhalation | Move to fresh air; seek medical attention if symptoms persist |
| Flammability | Not flammable |
| Storage | Store in a cool, dry, well-ventilated place |
| Disposal | Dispose of in accordance with local regulations |
Notes about Saftey¶
When using Smooth-On’s Smooth-Sil platinum silicone or PMC-746 urethane rubber, safety should be your top priority. Always work in a well-ventilated space so you’re not breathing in any harmful fumes. For both materials, wear safety goggles, long sleeves, and gloves—vinyl or nitrile gloves work best, because latex can actually stop the silicone from curing properly. Be careful about what surfaces you’re working on too—some materials like certain clays or untreated wood can mess up the curing process unless you seal them first. With PMC-746, extra care is needed. It contains chemicals that can be dangerous if you breathe them in or get them on your skin or in your eyes. Never heat it or spray it, and always use it in a space with good airflow. If it gets on your skin, wash it off right away with soap and water. If it gets in your eyes, rinse them for 15 minutes and get medical help. These materials are powerful, but they can be dangerous if you don’t handle them with care.
Testing Different Casts - Cooper Cumbus¶
On the left is the Clear Amber material and on the right is the Smooth-Sil 940. I think that the clear amber looks better since I double checked the mesurments and wasnt using materials that had been left out in the open for a long period of time
Comparing A Milled Mold to a Printed one - Amalia Bordoloi¶
Up until this point, our group had all made 3D printed molds so we just made a new mold for a wax to test with a different material. I made a duck mold based off this picture
Heres the final result of the milling:
Heres the process I went through while making it:
First I sprayed the mold to make it non stick
Then I mixed the two parts of the amber silicon together
Finally I poured the mix into the mold
The next day, this is what the cast looked like:
And heres what it looked like next to the 3d mold cast of the same material:
While the milled mold gave a smoother result compared to the 3d printed mold, it is easier and quicker to make and print a 3d mold. This is becuase you do not need to watch the mold be made with the 3d printer while I needed to watch a 40 minute mill for the wax mold.