Week 14

After thinking for a long time about what model I wanted to create, I decided to go again with my favorite “Granny” model 😄

The reason I was thinking so long is that I really don’t like working with 3D software, and I couldn’t get Fusion360 running on Ubuntu.

Anyway, since “Granny” only existed in virtual form, this was a good chance to bring her to life and have her always with us. One thing I really like about FabAcademy is that I can both program and physically touch what I create. Now it’s time to touch “Granny” 😄

For that, I took only the face of “Granny” from the image, removed the background, and used an online 2D to 3D tool to give it a 3D effect. Then I opened it in Blender to refine it, because the online conversion created a lot of rough surfaces.

So I switched from Object Mode to Sculpt Mode, then used the Smooth tool to clean and refine the surface.

Here is a short video of the process — and sorry to all Blender gurus, it’s my first time using it 😄

I am happy with the result, I even opened “Granny’s” breathing 😄

Then I pushed “Granny” into the cube so that only the back layer remains outside.

After that: Selected the cube, Opened Modifiers, Add Modifier → Generate → Boolean

Used the eyedropper to select the “Granny” object

Now the result is visible. After confirming everything is correct, I deleted the “Granny” object.

After that, it was ready for printing to get the mould. I printed it using a 3D printer.

For casting, I first used silicone material.

I used Best Mold 10, which is a two-component liquid silicone.

According to the instructions, the ratio should be 100:2 (A:B).

I mixed: 50g of A and 2g of B

Before pouring the material, I also decorated “Granny’s” hair with flowers 😄

It was written that I should wait 12 hours, but I couldn’t wait and removed it after 5 hours 😄

Here is the result. As we can see, even though I carefully fixed the nose in Blender, the silicone didn’t reach that part, and now we have a nose-less Granny 😄

But we don’t get sad — I decorated “Granny” using threads 😄

Now I needed to think what else I can pour into the mould to get my “Granny”. From our Group Assignment experiments it was already clear that gypsum would not come out from my mould, and the rubbers are expired — they work, but with difficulty.

So I decided to use biomaterials. I’ve always been interested in creating things with biomaterials, and we also have a Fabricademy instructor in our lab, who has been specializing in this field for more than two years and has many amazing works. Here is Erika Mirzoyan amazing page.

I asked her to help me create a material that would not dry too much over time, so my “Granny” would not shrink and deform. She suggested using one of her experiments, which is clay-based. The good thing about this material is that we can always melt it again and create a new form. She also mentioned that every time you melt it, the quality becomes even better. So now I have a really nice material to melt and bring my “Granny” back to life again.

Here are the components Erika used to create this material.

• Gelatine 12g
• glycerol 10g
• water 60ml
• clay 5g
• few drops of soap

I divided this piece into several parts, added water, and started mixing it continuously over heat.

When I felt that all the big chunks had melted, it was ready to use. Since it cannot become perfectly homogeneous, I ignored some small lumps and used a filter to pour it into the mould.

Here is how it looked after pouring, and after leaving it overnight, I could feel it had dried, so I removed it.

It turned out just perfect. I’m really happy both with the mould and especially with Erika’s material ❤️

I also did some experiments with “Granny”, trying different forms in the lab 😄

These photos are taken one day later — you can already see how much it shrank, and also small cracks appeared, and it became drier.

This photos after 2 days.

This photos after 3 days.

This photos after 4 days.

Granny with CNC machine

I wasn’t fully satisfied with this result, so I also tried to create the “Granny” mould using a CNC milling machine. It was not an easy or fast process, so here is how it went.

Since I worked on the 3D model in Blender and it doesn’t generate G-code, I exported it as an .svg file to use with mods.org.

I opened “G-Code Mill 2.5D STL”, selected my SVG file, then selected a 1/16 end mill (1.5875 mm), calculated, and checked the result. I chose this size to gradually reach a clean final result without damaging the mould.

Here is the result — you can already see the rough shape of “Granny”. The CNC machine took about 40 minutes. I’m satisfied 😄❤️

Then I generated another .nc file, this time changing only the end mill size to 1/32 inch (0.79375 mm).

After calculating and checking, I sent it to the CNC machine, changed the tool, kept the same XY coordinates, and re-zeroed Z.

Here is the result — “Granny” became more clear. This also took about 40 minutes.

The final step was to use a 1/64 end mill, but this time I opened “G-Code Mill 3D STL” for a more detailed result and set the tool size to 0.396748 mm.

After calculating and seeing the 3D preview, I understood this would take a long time… and I was right — it took 12 hours 😄

But it was worth it. It looks so good that honestly, I could leave it empty and still be happy 😄

I poured the saved biomaterial again after melting it with water. But this time I added too much water, so it will take longer to dry. Since I can’t wait too long, I removed it after 5 hours.

Because I planned to pour it into wax, I waited some time before pouring, but it seems I waited too long — it became harder to pour, and I noticed air bubbles inside after removing it.

Still, the wax version turned out more detailed.

So now we have two bio-Grannies 😄

This photos after 1 day.

This photos after 2 days.

This photos after 3 days.

I will continue experimenting and try to create more “Grannies” with different materials 😄