Molding and Casting
Design a 3D mold, machine it, and cast parts from it
This week I have been trying to make a chocolate ring. I cannot afford a million dollar jewel but I can try to make something that would be more precious thing depending on who is asked about.
Preliminary sketches of the jewel. Saphire mounted on white gold...
Modeled on Rhino, It has a deliverate cartoon aspect.
Image of the final mold drawing in Rhinoceros. It will be formed by two parts. I have added two diferent pipes in order to strain the liquid chocolate and another one to allow the air going out.
Grayscale image of the mold. first I tried to mill it using The Modela and the Fabmodules but it did not work. Finally, due to the size of the mold I decided to try milling it using the big CNC.
I decide to divide the milling process in three carving phases. First rough one with 6 mm. tip and another two finishing phases, using 3 mm. tip and cutting direction at 45 and -45 degrees.
Milling process, quite fast and soft.
After the first carve phase, the surface seems nice but a bit rough.
Final result of the mold, ready to use.
I applied demolding spray on the mold but I really might have been unnecessary.
Actually the demolding proccess was very easy.
NOTE: I read about the safety specifications of this product although I didn’t find any kind of negative note about its suitability for food use could have been much better to avoid its use in order to ensure the food safe chain.
Smooth-Sil® 940 is suitable for making baking molds and trays, ice trays, casting butter, chocolate and other applications used to produce foods.
Shaking the mix without rest to the point that the mixture turns uniform and homogeneus. probably the most boredom phase of the process.
Pouring the paste and shaking the filled mould smoothly during ten minutes. All the air went up to the surface as can be seen by the bubbles.
Post cure requirement: after rubber mold has been allowed to cure for 24 hours, expose to oven heat at 212° F / 100° C for 4 hours. Let cool and wash mold cavity thoroughly with dishwashing detergent/water solution. Rinse thoroughly and allow drying before using.
Final result!
SHARKS again!!
Some weeks after molding assignment I retry to mill a 3D model using the Modela, and I designed a new shark model. My aim objective only was to practice with this machine, so I decided to make an small object using expanded polyestirene. Although I was not trusting very much in the behaviour of this kind of material I supposed that It was a good opportunity to verify it.
The mighty model!
Different screens about the parameters used to generate the code
The Modela in action! During the proccess I realized that the cutting speed could be grown as well as minor adjustments on the rotation speed of the tool. Even the steep amount of the tip had been posible to be increased.
Final model