Skip to content

8. Moulding and casting

This week I worked on moulding and casting. Milling the mould implemented using a CNC milling machine.

Cast Materials

Cement Maerial

Maerial Name


Precautions for safe handling

Protective measures: Put on appropriate personal protective equipment. Avoid exposure by obtaining and following special instructions before use. Do not get in eyes or on skin or clothing. Do not breathe dust. Do not ingest. Wear an appropriate respirator when ventilation is inadequate. Keep in the original container or an approved alternative made from a compatible material. Empty containers retain product residue and can be hazardous. Do not reuse containers. General advice on occupational hygiene: Eating, drinking and smoking should prohibit in areas where this material is handled, stored and processed. Workers should wash their hands and face before eating, drinking and smoking. A key to using the product safely requires the user to recognize that portland cement reacts chemically with water to produce calcium hydroxide which can cause severe chemical burns. Every attempt should be made to avoid skin and eye contact with cement. Do not enter a confined space that stores or contains portland cement unless appropriate procedures and protection are available.

Casting Process

In order to achieve workability for casting, a more typical w/c ratio used to cast concrete is 1:0.5+ (100g cement : 50ml+ water). This ratio can change depending on a variety of factors including the use of vibration or the addition of chemical admixtures.

Cure Time

Curing time of cement is typically 24-48 hours.

Work Time

Depend on the amount, generally 30 minutes.

Mix Ratio

Tipically w/c ratio used to cast concrete is 1:0.5+ (100g cement : 50ml+ water).

Cured Material State

Cured Hard

Cement Casting

The amount used was 3grams of cement and 1.5 grams of water, where it has satisfied the ratio of 1:0.5 Adding water I have mixed the cement and water I have used glitter to decorate my cement I have added the mixture to the template and leave it for 24 hours to dry

Group Assignment

My colleagues’ works:

Hanan’s research Ali’s research Yousif’s research Mohammed’s research Melad’s research Sara’s research Hafsa’s research


3D Design

The star is designed using tinkercad website.

Note that the laser cutter has the following dimension limitations:

I have added a built in star shape from tinkercad with dimension: X=50mm Y=50mm Z=8mm

From export I have download my design

Star TinkerCad link

Laser Cut

Export the stl design file into SPR Player Adjust the origin in the center I have used double sided tape to stick the wax on the board I have created the toolpath with the size of the model Here is the PN used by the machine Note that you have to wash it and clean it from waste before the moulding step


For the mould, I have used GR silicon with a/b ratio of 1:1, where I have used 23 grams of each It takes 24 hours to dry


I have used soap for casting

Another casting material 10 grams of resin mixed with 6 grams of hardener


I haven’t had any problems this week But it required accuracy in ratio and fabrication procedures

Hero Shot

Design Files

moulding moulding

Last update: June 18, 2022