My name is Andi and I'm an engineer here
at Sintratec.
We are a Swiss startup that makes SLS 3D printers.
We have a new machine coming up - the Sintratec S2.
So as you might expect we are doing a lot
of testing with it right now.
To demonstrate the strength of its parts I
designed a functional electric ducted fan
driven by an 800 watts  RC brushless
in runner motor.
Our goal was to see how much power the part could handle without being damaged.
Once the design was done I printed the
part with our strong PA12.
Next I balanced the fan with some lead balls around the rotation axis.
Soon I was able to hold the prototype in my hands that was ready to be tested.
For that I tied the EDF to a metal cord and mounted it onto a rail which I clamped on a table.
With proper safety distance and wearing safety goggles I started the engine and
increased the speed slowly step by step.
However we decided to abort to test at
around quarter to full speed
because were worried about all the powder coming
out of the front.
After investigating it was clear that this resulted from a design flaw
where a small inner area was not
closed.
For the print to sustain the rulting forces stability was a crucial aspect but not easy to achieve.
In my first prototype I left the shell hollow which resulted in the EDF being too soft and pliable.
so I had to enforce the interior walls with additional structures.
After printing the part again we were ready to redo the test.
This time I fixed the EDF onto a more
stable workbench and increased the power again.
But then I noticed an imbalance of its
spinner.
To make sure it was stable I decided to remove it and continued without that.
We also added some smoke to visualize the airflow.
The peak power was about 1,400 watts an
impressive result in my opinion
considering the motor has a nominal
power of 800 watts and the EDF survived
without any damage at all.
I think this test showed the strength of the Sintratec PA12 powder
combined with the efficiency of our S2 makes for very durable prints.
