Unfortunately, once you put absolutely ANYTHING on the internet, with whatever passwords and precautions you like, you can pretty much say it's then in the public domain and would then be available to non-Members and Members alike.
If the likes of Microsoft, the big film companies and music labels can't stop their stuff being pirated, what chance do we stand with our little magazine that goes out to just a couple of thousand people?
The only way to stop it being pirated is to not to produce an electronic version in the first place.
This is also one of the reasons why our Machine Researcher and Registrar are completely against any of the Works records being made available in an electronic format. They're too easy to copy and open to abuse by anyone who stands as a Club official for dubious reasons.
Similarly, our Technical Committee are not allowed to hold copies of drawings (except for evaluation purposes). The only people who have full sets of drawings are The Drawings Manager (I think) and The Spares Company. Electronic versions of the drawings are held by an undisclosed Member (not me before you break into my house to try to steal them!).
Hopefully there are secondary masters (and electronic copies where applicable) of both VOC drawings and works records held in separate physical locations? Likewise for electronic copies of MPH held for the future.