Week10

Molding and Casting

I decided to create mold and cast an Adinkra symbol, Gye Nyame. I used a 2D SVG that I already had for making jewelry. I wanted to create the symbol to create the symbol in 4 different sizes for jewelry making. 
The dimension of my wax block was 152 mmx 76mm x152mm so i had to design a 3D model of the symbol to use for the mold.

I used Tinkercad to create my mold for this assignment. I made a box and extruded it using the dimensions of my wax block (152 mm x 76 mm x 152 mm). Next I made small box that was 100 mm x 40 mmX 100mm and then inserted the box into the larger box and used the hole function create a hole pocket on the topside of the larger box.
I imported the symbol using an SVG file that I created in Inkscape.
I placed for symbols inside of the hole in the box and then extruded the symbols to 25 mm and group all features together. I added a slanted walls on the all sides of the interior box. I grouped all features together and saved the STL file. I imported my model into VCarve to generate the code for the Shopbot.

I loaded the STL file and defined the rough and finishing toolpaths and deed rate.

I used a 1/8 up-cut, 4 flute, end mill in the tool path parameters and in the Shopbot. I downloaded the a gcode file and uploaded the file in the Shopbot Control System software and ran the job. Next, I fixed the wax block on the ShopBot Table using double sided tape zeroed X, Y and Z and launched the roughing toolpath and finish toolpaths.

Here’s the result:

The end mill was too large and some of the details of the design. Next time I will use a 1/16 up-cut, end mill to ensure that all details of the design are cut out.

I used Omoo 25 to make the cast. I poured equal amounts of parts A and B in seperate cups and stirred for about 30 seconds.

I put the mixed compound into closed container connected to air compressor to extract air and gas from the compound. I left the compound in the container for about 30 seconds until it rose and then related the air valve and repeated the process once. Next, I poured the compound into the wax mold. Although the data sheet indicated that the compound would be cured in 75 minutes. I checked the cast the next day.

Here is the end result.

Design Files - 3-D Model - V-Carve - Shopbot