Introduction: Sand Casted - Knife Holder
My first trial of sand casting technique combined with 3d modelling and 3d printing.
I modelled the imagined object in Rhinoceros, printed it using Ultimaker 3d printer and casted it in aluminium.
The final result did not turn out quite as expected. Still, the combination of techniques can give great results when done with precision and with a bit of practice. I am sharing my test.
To follow the same process you will need :
Rhinoceros 5 ( or any other compatible 3d modelling programme)
Cura or Slic3r
3d printer (FDM principle)
Sanding paper or a file
Burner / blowpipe
Frame / box / (filled with sand)
PLA or ABS filament
Step 1: 3D Model
Download the file ( you can try using the exact same as I did or alter the dimensions of the gaps to avoid the mistake in result that I got )
Print the model using a 3d printer.
Step 2: Surface
Depending on the chosen filament, thickness of the noozle and settings in 3d printing software your model will have a certain surface texture that you may want to avoid having on the casted model.
In case you want your aluminium model to be as smooth as possible use a sanding paper or a file on a 3d printed object.
Step 3: Prepare
Fill the box with fine sand capable of keeping the form and prepare other tools.
Use a tool to make sand surface flat and solid. The model will be placed on top of it.
Step 4: Imprint
The position in which the model is placed before casting depends on its geometry. We want to both leave a good imprint of its shape in the sand and think of how we are going to pull it out after the imprint was made.
I made two wholes screws or sticks can be inserted into to help with pulling out of the model.
Step 5: Melting Aluminium
Fill the iron pot with aluminium and melt it using a burner / blowpipe at the right temperature.
Aluminium will melt relatively quickly. Its melting point is around 660 °C.
If you are making multiple models and need to keep the metal liquid between pouring, place the pot in the workshop's oven.
Step 6: Casting
Pull the model out of the sand and fill the imprint with liquid aluminium.
Wait for it to harden.
Step 7: Result
After the aluminium has hardened take the model out and rinse with cold water.
The reason my model did not turn out as intended are some of its narrow gaps that had sand stuck between them. To optimize your version you can widen the gaps or make some of your own alternations in software.