Battlestar Galactica Case Mod by Boddaker

The Airlock

Going back to the side panels, for the right hand side I wanted to do something different here for the window as well - the case as a whole has more than the one side that people normally just concentrate on. In keeping with the Galactica theme, I came up with the idea to do a mechanically sliding airlock door.

This proved to be easier said than done, for it took me four redesigns and major alterations to the chassis before I got it to work. Even then having learnt a great deal in mechanical engineering, it was spotty at best. First I used a sheet of clear acrylic as a base, then made a dummy door was laid on top that would curl neatly around the rollers.

The gaps to allow it to bend were the same 5/8" apart that the rest of the case ribs used to again keep the style intact. The idea was that the acrylic with bars added above and below would keep it straight by guiding it back and forth.


My first attempt was a two-door set up, with rollers mounted in their own module inside the hard drive cage, each connected to a servo. In theory, it worked perfectly; the servo would turn the roller onto which the segmented door would roll up much like a roll-up garage door, only sideways. Opening the door (rolling it up) was the easy part, however, making the door close (extending it back again) was a totally different story.

I couldn’t get the servo to push the door back to the closed position because the segments wouldn't translate the force forwards, instead the door would just bunch up at the turn. I abandoned the two-door set up in favour of a single door set up with two rollers: one roller to pull the door open, then other roller to pull the door back closed. Having a servo connected to each roller, I needed to synchronise them up so they would both be running at the same speed, and in the same direction. Again, this proved more difficult than I thought, due to the slight variables in speed for each servo.


One would inevitably turn faster than the other, causing the door to bind, or loosen too much depending on which way the door was moving. Finally I ended up using only one servo for both rollers, simply connecting them with a long O-ring drive belt. This seemed to work the best, even though the rollers weren’t perfectly centred. For reasons beyond my comprehension though, the door still gets mis-aligned after a few open/close cycles. Go figure!