Saeed's Week 16

Assignment

Group Assignment:
- Review the safety data sheets for each of your molding and casting materials
- Make and compare test casts with each of them
Individual Assignment:
- Design a 3D mould around the stock and tooling that you'll be using, mill it (rough cut + (at least) three-axis finish cut), and use it to cast parts.

Evaluation Standards

Link to the group assignment page
Review the safety data sheets for each of my molding and casting materials, then make and
compare test casts with each of them
Document how I designed my 3D mould and created my rough and finish toolpaths for
machining, including machine settings
Show how I made my mould and cast the parts
Include my design files and ‘hero shot’ of the mould and the final object

Output Preview

Fusion360 MODELA Player 4

Group Assignment

The Mold material

We found some of Silicon Rubber and Hardener in the lab's inventory. It seemed to be purchased from a local distributer because the package had Arabic writigs.

I tried mixing the materials in using the ratio written on the package (100A:1B) and it failed to harden. I re-tried to mix it using a (10A:1B) ratio, and it got right after around five hours.

The Casting material

We also found a Solvent Free Transparent Epoxy in the inventory.

I tried mixing the materials in using the ratio written on the package (2A:1B) and it became totally hard in five hours.

The safety instructions were written in Arabic on the package. It says:

The work area must be well ventilated
Protective gloves and safety glasses must be used
If anything got spilled on hands, it must be washed very well
If it reached the eyes, it must be immediately washed, and a doctor must be consulted
It's a bad idea to smoke or eat while handling these materials
The package should be stored in a temperature less than 35°C

Mold Design

I've never done molding before. I decided to make a simple design where I can try the concept without worrying too much about the design.
I opened Fusion without a plan and began sketching. I came up with this simple blade design; where I lofted surfaces between a point and a rhombus.

I sliced the body in half in order to build the mold around it.

I built the mold by extruding a bottom, four walls, and two registration pins. It made a mistake where I made the walls equal the same height of the top point in the design. The walls should go higher that the design in order to have the poured material covering each point in the design without getting spilled over the edges.

I finally combined the two molds in a single body in order to have it manufactured in single process.

Mold Fabrication

I used MODELA PLAYER 4 to generate the toolpaths and operate the machine. I opened my saved and it appeared in that weird wire-frame view.

I used a 1/8'' ball end-mill for roughing and 3/32'' ball end-mill for finishing. Those end-mills were not defined in the software. I added them by opening the Add/Remove Tool wizard.

I created two new tools and defined their diameter.

I then selected the material that I'm going to mill. It's modeling wax.

After that I defined the model orientation and origin.

Next. I made sure that the model setup is okay. I didn't change anything except for the margins around the model.

The model setup is now complete.
The next step is to define the process to do. It starts by defining the roughing process. I changed the end-mill, toolpath type, and speeds according to the settings shown in the following screenshots.