8. Moulding and casting¶
This week I worked on design a 3d object (with some limitation due to the number of axes of the device and the bit size) and creating and moulding it, then casting it. In addition, tried a molding material and reviewed its safety and properties.
Group Assignment¶
In this assignment, we worked on trying and testing different for moulding and casting. I worked specifically on Art Coating Epoxy (Resin).
Resin (Art Coating Epoxy)¶
Safety¶
1- Good ventilation (or use a Respirator).
2- Gloves and Safety Goggles.
3- Protective Clothing.
Process¶
I looked at the container of the material to get the process of preparing it:
1- Put part of Hardener (B) to each 3 parts of Resin (A), preferably Starting with part (B).
2- Mix them well for at least 3 minutes, transfer it to another container and mix again.
3- Pour the Mixture into your project. It will start to level on its own. You can pop the bubbles using flame.
Cure time¶
48 Hours in room temperature.
Work time¶
40±3 minutes, in 23±2 ℃.
Mix ratio¶
3A:B.
End result condition¶
Hard result.
Other materials¶
Individual Assignment¶
Design:¶
I’ve first made the design using fusion360 from this picture:
Milling:¶
Milling is done using the device:
Roland SRM-20 | Desktop Milling Machine
It is controlled using a Computer:
1- Specifying Model size and Orientation:
2- Type of Milling:
3- Creating toolpath:
4- Preview Cutting:
5- Setting Origin point:
6- Start Cutting:
First Try Failed: Because that the depth of material wasn’t chosen correctly, so all the around of the designs was cut.
Retry:¶
workpiece size changed from 10 mm to 8 mm:
Roughing bit: ball of size 2.38 mm:
Finishing bit: flat of size 0.79 mm:
Moulding:¶
I choose the silicon rubber material:
and followed the instructions written on the containter:
Mix ratio: A:B=1:1
Safety: Silicon is safe in general. But maybe injected silicon move through the body, and this will cause serious health problems. So to be safe, we need to wear gloves.
Process Mix part A and B evenly 1:1, and then pour it in vacuum to get rid of bubbles. Then, pour the mixture into a mould and let it dry.
Pouring the mixture:
I take it after about two days:
Casting:¶
I used resing to make the final shape I want (Cast):
Mix ratio: Resin:Hardener=10:6
Safety: Wear gloves and have good ventilation (or wear a mask).
Process Mix part Resin and Hardener according to ratio 10:6, stir the mixture for 3 minutes. Then, pour the mixture into a mould and let it dry.
Acknowledgement¶
I take the mix ration, safety and process parts for moulding and casting, from Batool and Hussain group assignments, respectively.