Molding & Casting

Group Assignment

Link for the group assignment

Individual Assignment

For this week I used 3 essential materials for the 3-Steps mould and casting

Polystyrene FOAM® density 30 Kg/m3:

ZA 22 MOULD : RTV silicon rubber.You can find the Datasheet of This silicon

Choclate /paraffin wax …

Safety :

ZA 22 MOULD : The preparation is not to be considered hazardous in accordance with directive 88/379/CEE and subsequent amendments.

Designing the Mold

For this week I'm going to do a design for a biscuit piece because I want to test it with chocolate. So the first this I do is to create the sketch

Then I create do form >> revolve

Create Symmetry >> mirror

Select faces >> edit form

The next step is to design the external part that will contain the material.

Moving now to the CAM , set the configuration , Create new set up to define the stock and set the work coordinate system.

Then,to do the 3D contor operation.Click 3D >> Adaptative clearing

Then I set set the configuration , choose the tool

Then I simulate the job to check if there is any problem like collisions,.. and you can also have an estimation on the machining time

You can find HERE the fusion file of my design

Milling the Mold

As a result of the CNC job, we endup with something like this.

Preparing the plastic mold

Take the two bi-component products supplied by Zhermack (base and catalyst) and shake before use. Weigh an equal amount of catalyst and base (im my case ,after calculating the volume I mixed 75ml of silicone with 75l of catalyser). Once the product is weighed and it is assured that the base and catalyst are equal, the two components areinserted in a recipient and mixed thoroughly. It is important to check while mixing that no residue remains on the base and sides of the recipient. Mix energetically until the colour of the product is homogeneous.

Mix energetically until the colour of the product is homogeneous. Once the product is mixed it is poured, preferably 30cm above the recipient into the mould.

The setting time or cure time (time the silicone needs to vulcanize) is about ST at 23°C 60 min start counting from the mixing process.And after 60 minutes, we can start de-molding.

Casting

For the casting ,As I said I will use choclate and also paraffin wax. Lets start by the chocolate , it is important to mention that this type of silicone is not food safe, it is necessary to use a alimentary silicone but since it is not available in our country, we chose to use this silicone, so the cholocate used is not for eating. . Moving to the kitchen, I used chocolate bars that I bought when I bought my goods. To prepare them, I'm going to put them in a water bath. When the chocolate starts to become liquid I poured it into the mould.

Then I put him in the fridge for an hour. and this is the final result

Moving now to the paraffin wax , to know more about this material I watch this video explaning the process of the production of candles

I repeated the same process but on a small enough quantity for my piece.

After 5 minutes , this is the final result