For this assignement, I have decided to make a mold in order to produce chocolate cat! The master mold will be make from extruded polystyrene and machined with a CNC
I have made my design on Fusion360 :
Prepping the mold for casting
I have now my master mold, I can produce the silicone mold. I will set-up 4 pieces of cardboard with to create the formwork around it
Now that's the fun part : I have to find the right amount of silicone to fill the mold. The final mold needs to be at least 10mm thick to ensure that the mold doesn't tear.
I can use Fusion 360 to get the answer but let's try it the old fashion way.
Now that I have that quantity, I also know that I need 12.5ml (5% of the amount of silicone) of silicone hardener I need to put into the mix.
Release and first try of the mold
24H later, It's time to see if everything went fine. I was a little stressed :)
It's time now to test the silicon mold and what's better than chocolate? I will try to produce a chocolate cat from the mold
I'm not a very good cook but let's go!
Lessons learned and possible improvements
Now that I understood and tested the whole process, It much easier to see the flaws of my firt mold :
I should have design the mold in full 3d not in 2.5d
During the design, I have to think how to avoid any sharp line or form,like the tail of the cat, to facilitate the unmolding
I don't need to make the mold so thick, next time I can save some material (quite expensive by the way)
Update
During a review, my instructors have pointed out that my master mold (the cat) was in 2.5d and not 3d.So I have use something in 3d (yeah for the kiwi and thanks Ben!) and the same teps have been taken in order to complete the assignement at 100%.
Once the mold is dry (24h), I will updated the page :)