Making molds out of sand (…and sunlight)

Hi everybody,
this pretty dated video is always inspiring.

I think that this could be a good way for making molds for metal.
At the end also sand (glass) is a good “plastic” material, relatively easy to find…
In many developing countries sun is pretty accessible and sand too…
What do you think?
Another good alternative would be to feed the 3d printing process with a syringe filled with clay…

The process shown in the video results in a very porous surface, which makes plastic stick to the walls of the mould and make it impossible to remove without destroying the mould. If you could fully melt the sand to a glossy surface the adhesion problem would go away, but it would not be a very strong material and the work involved in making the mould is simply not worth it. If you want a cheap option for moulds you could try concrete.

Ok, try it and let us know the results.

Thanks Olivier!
absolutely true, but in some cases, imagine for example the lost-wax technique, the mold is for a single use…. in some cases it’s worth… 🙂
Beside that, the mould can be smoothened with a grinding tool.
another option is to use a torch, the torch glasify the surface and makes it glossy smooth…
We can try…
let’s call for a challenge on that 🙂