WEEK 14 - Molding and Casting

The group assignment for Week 14 focused on understanding the complete molding and casting workflow from a material, safety, and process perspective. As a team, we analyzed different molding and casting materials, reviewed their Safety Data Sheets (SDS), and identified the correct handling procedures, personal protective equipment, curing conditions, and possible risks associated with each material.

This group work was important because molding and casting processes involve chemical materials that require controlled preparation, accurate mixing, proper ventilation, and safe demolding practices.

1. Reviewed the group assignment results, including material behavior, SDS information, and safety recommendations.
2. Selected the cat face model from Printables as the base geometry for the individual mold.
3. Prepared and adapted the 3D model in Fusion 360 to create a positive master mold.
4. Prepared the CAM process in Aspire by defining stock size, origin, toolpath strategy, and machining parameters.
5. Generated and saved the CAM files for CNC Router machining.
6. Machined the mold using a CNC Router and a 6 mm End Mill.
7. Sanded and sealed the CNC mold to improve the surface finish.
8. Prepared and poured the silicone into the CNC-machined master mold.
9. Demolded the flexible silicone mold.
10. Prepared, poured, cured, and demolded the final EPOX-21 resin casting.

The individual mold was developed from a kitten face relief model. The original geometry was downloaded from Printables: Cat Face model. After downloading the file, I imported and prepared it in Autodesk Fusion 360.

The original decorative relief was adapted into a functional mold master by adding a rectangular base, surrounding walls, and enough containment area for silicone pouring.

After finishing the digital design in Fusion 360, I used Aspire to prepare the CAM operations and generate the toolpaths for the CNC Router. In Aspire, I defined the stock dimensions, material thickness, machining origin, tool selection, roughing operation, finishing operation, and toolpath preview.

A 6 mm End Mill was used to machine the mold. The strategy removed the material progressively and created the mold cavity, border, and cat face relief.

The CAM files used during the fabrication process are published in the archive folder. These files contain the Aspire machining setup, tool selection, stock configuration, roughing toolpath, finishing toolpath, and cutting parameters.

The cat mold was fabricated using a CNC Router. The machine followed the CAM files generated in Aspire and removed material layer by layer until the face, ears, eyes, nose, whiskers, and surrounding cavity were created.

After milling, the mold was corrected by sanding. This step was necessary to reduce the toolpath marks and obtain a smoother surface finish.

The milled mold was sealed before pouring silicone. Sealing reduced the porosity of the wood-based material, improved the surface finish, and helped the silicone release more easily after curing.

The silicone mixture was poured slowly into the CNC-machined mold. Pouring from one side allowed the material to flow naturally across the surface and helped reduce trapped air.

After curing, the silicone mold was carefully removed from the CNC master. The flexible mold captured the cat face details and was ready to be used for resin casting.

For the final casting stage I used EPOX-21 epoxy resin. The material included component A and component B. The resin was mixed slowly to avoid bubbles and to obtain a uniform mixture before pouring it into the silicone mold.

Once the resin was mixed, it was poured into the silicone mold. The resin was added slowly so that it could fill the detailed areas of the mold and reduce the formation of bubbles.

This hero shot presents the complete result of the molding and casting workflow. Starting from a digitally prepared cat relief, a CNC-machined master mold was fabricated, improved through sanding and sealing, used to produce a flexible silicone mold, and finally cast with EPOX-21 epoxy resin.

The original kitten relief reference was downloaded from Printables and later modified in Fusion 360 for the molding and casting assignment. The final Fusion 360 file documents the adapted mold design used for CNC Router machining.

To address the evaluation feedback, I also included the CAM files used during fabrication. These files document the Aspire setup, roughing operation, finishing operation, selected tool, trajectory, and CNC preparation used to fabricate the mold.

• Linked to the group assignment page and reflected on my individual page what I learned
• Reviewed the safety data sheets for each molding and casting material
• Documented how I designed and created my 3D mold, including Fusion 360 preparation, Aspire CAM setup, CNC Router machining and the 6 mm End Mill
• Documented detailed machining parameters, including spindle speed, feed rate, plunge rate, pass depth and stepover
• Added CAM evidence with the full-width toolpath trajectory image and the Aspire tool database image
• Published the CAM files used during fabrication as downloadable archive files
• Ensured the mold has a smooth surface finish through sanding and sealing
• Shown how I safely made the mold and cast the parts
• Described problems and how I fixed them
• Included design files and hero shot of the mold and final object