12. Molding and casting¶
The assignment this week reaquires to design a mold around the stock and tooling that we can use to create shapes in diverse types of materials. It is interesting to mill it using different depths. Previously I have used the image bellow to design the vinyl cut. I decided to use it again to create the mold for then make something that my daughter can play and enjoy it (she loves panda).
I started the assignment drawing the image in a shape using fusion360 using different depth.
I added the necessary parameters for the drawing.
I have added a square in a simple sketch with the dimensions width X width.
Create a extrude for the square which will represent the material we have available to make the mold.
Edited the image using inkscape. Create the bitmap of the image to extract the lines; removed all points not necessary added from the bitmap; and adjusted to keep the same image lines. This is an important step because fusion accept to add SVG files in the sketch that can be used in the designing. This way it was possible to create the shape of panda in the design of the material.
Import the SVG file of the panda into a sketch using the top of the material and turned to fit the center of the material. I had also to adjust the scale to make it bigger.
Create an extrude of the white part of the panda with the depth of thick_mold (first layer).
Create another extrude, now of the black part of the panda with the depth of thick_mold/2 (second layer).
Preparing for milling¶
The generated file from the drawing, it was imported in the software MeshCAM, used to create the file with the paths that will be send to the milling machine. The parameters used is shown in the images. I have used the milling machine Nomad 883.
The resulted mold for the casting has some grooves because of the needle used to mill it. To fix this, I should use a different needle to make the mold more smooth. However, to save time I decided to use the mold with the grooves to make the casting.
The resulted mold from the milling machine can be used to casting the object using different materials. For testing it, I have used a blue silicone that is a flexible material. The material is compoud by two fluids that once mixed, became the silicone. They were mixed in the proportion of 50-50 regarding their volume. The silicone has a ratio of 100-60. When the silicon was hard, i could remove it from the mold and the shape of the panda can be seen.
Burning to remove the bubbles from the casting.