As you can see from the photos, the watch towers are based on a similar design to that used as the look-out post in the gantry system. In fact the whole wall system is based on a scaled up version of the look-out post.
As such the work to develop the walls was very simple. It got more interesting when I moved on to designing the door. I decided I would make it a movable door so that a player could have it open, closed or indeed open and close it during a game (as the patrol makes a dash for the door while the horde of bugs advances on the fort).
The door frame is build up of three layers, the outside, the inside and a spacer layer between. The doors have simple runner attachments at the top that sits over the inside wall. So that the door always closes in the correct position I have included a small stop in the middle at the top of the inside wall, which stops the doors passing the halfway mark.
Most of the fort is built in 3mm MDF, however, the look-out posts on top of the watch towers, the wall walkways and the stairs are 2mm MDF and the spacer in the door wall is 4mm (to allow the door to be painted without jamming).
Just as a little extra, a friend of mine is working on a 28mm scale Ork Gargant and asked me to knock up a circular saw for him, this was the result:-
Note: The minis in these photos are the the 28mm figures I sculpted for Defiance: Vital Ground!