13. Molding and Casting¶

view checklists

Checklist: personal
- DeepL check spelling, grammar
- repair file links, replace .png -> .jpg; .mov -> .mp4, .webp
- remove audio from video, compress
- GPT check for better markdown
- compress all files before push
- create Luedo Chocolate mold
- read safety instructions, document on personal site
- research personal protection equipment in the lab
Checklist: Nueval: Student's checklist
- Linked to the group assignment page and reflected on your individual page what you have learned
- Reviewed the safety data sheets for each of your molding and casting materials, then made and compared test casts with each of them
- Documented how you designed and created your 3D mold, including machine settings
- Ensured your mold has smooth surface finish, that does not show the production process (by postprocessing if necessary)
- Shown how you safely made your mold and cast the parts
- Described problems and how you fixed them
- Included your design files and ‘hero shot’ of the mold and the final object
Checklist: Task list Class/Nueval
- Group assignment:
  - Review the safety data sheets for each of your molding and casting materials
  - Make and compare test casts with each of them
  - Compare printing vs milling molds
- Individual assignment:
  - Design a mold around the process you’ll be using, produce it with a smooth surface finish that does not show the production process, and use it to cast parts

view ideas

silicone gasket for Luedo lamp
LUEDO galvanic coating for the reflector
mold chocolate calender for christmas

Group Assignment ¶

For the Group Assignment we

reviewed the safety data sheets of all our materials related to molding and casting
compared the different materials and their properties
compared printing vs milling molds

My additions to the group assignment were:

proofread and double-check the safety data sheets

Individual Assignment¶

Casting Vocabulary¶

source: MEM-103 Manufacturing Processes

sprue (German: Anguss)
runner (German: Verteiler)
- for distributing the material in the mold
gates (German: Anschluss)
- connection between part and runner
riser (German: Steiger)

Milled Wax Molds¶

Chocolate Molds¶

This is our starter project for the molding and casting assignment. We decided to create chocolate pieces for a Christmas calendar. Steps:

Mill wax mold (positive)
Cast silicone mold (negative)
Cast with chocolate finished product (positive)

Milled Wax Mold¶

For the milled wax mold I started in Fusion360 and modeled the wax mold. First, I started with a rough model of the final wax mold to get the approximate dimensions. I included sloped sides to prevent interference with the end mill.

With this rough mockup, I modeled the actual target volume - the chocolate piece.

Then I imported the existing Luedo shell model from week02 into the project and created a design with letters and light beams.

After the complete modeling process was finished, I moved on and created the CAM files out of the 3D model.

This is a visualization of the tool path.

In this short video the movement of the tool head and mill is simulated in Fusion 360.

Here you can find the generated tool path: luedo_mold.cnc

After clamping the wax piece onto the machine bed and installing the right mills, we started the milling process for all our wax molds in our group.

The images below show the mixing process of the mold material. The silicone mold material is composed of two components, A and B, which need to be mixed very well.

After mixing the material, it can be poured into the mold and the degassing process can be started. For degassing, a vacuum container is used to eliminate all air bubbles in the silicone.

After 12 hours, the silicone mold can be removed from the wax mold.

Now the mold is finished and it can be filled with chocolate!

In the following video, the degassing process of the chocolate is shown. You need to tap the silicone mold on the table to help air bubbles rise more quickly.

This is the final result of our group's chocolate casting process.