Recommended
EEVblog #939 - How Is A PCB Manufactured?
Why people recommend it
Dave Jones' walk through a professional PCB factory, used to show how boards are etched, masked and silkscreened in practice.
Watch for: Pairs with his PCB design for manufacture video
In their words
Have a look at this EEVBlog video to see how this is done in a professional environment: [video] They use paint for the solder mask.
Bimpelrekkie on electronics.stackexchange.com, Jan 2017. CC BY-SA.
