FC-Architecter wrote: ↑Mon Jul 23, 2018 12:34 am
I do not know if it worked because the propellors are solid but the cylinder is transparent.
As TheMartkster wrote, you applied transparency to Cylinder before applying the Boolean Fuse. The Fusion keeps the colour and transparency of the original shapes. Another way to get rid of the transparency of the cylinder part of Fusion is to define a different colour than default grey.
FC-Architecter wrote: ↑Mon Jul 23, 2018 12:34 am
Also I seem to have 3 extra helixes.
You don't. Those are the 3 helixes you created and used for the Sweeps. They are just not hidden automatically by the Sweeps. Contrary to PartDesign, some Part operations don't automatically hide the objects they are based on.
Now, you haven't completed the model.

R-frank in his original video deletes the 2nd and 3rd sweeps and shows how to replicate them using
Draft Array.