Below is a short video showing the inner workings followed by some pictures with descriptions:
For this project, I attached a modified Swinging Log Trap piece (with the top sections cut off) to the middle section of a standard "T" corridor piece using pins and glue. This was to extend the length of the hallway that will house the motor, gears, and electronics.
|Section showing the pins before it's attached to the main corridor. This was actually a Swinging Log Trap|
piece before I cut the top sections cut off and covered the holes with putty. Sorry for the crappy photo...
|The extension piece (shown above) was glued to the main corridor section.|
The white putty still needs to be painted.
Next, I took a standard Dwarven Forge secret door piece and carefully cut the floor section off, leaving only the wall frame and secret door. The wall frame was inserted in the opening of the main corridor then glued in place. Putty was added in the gaps then shaped and painted to match the surrounding wall. I made a false backing piece to put behind the opening so that the hardware can't be seen when the trap wall is extended.
Using some scrap pieces of Dwarven Forge from a previous project, I constructed a long, straight piece and attached it to the back of the secret door. This "arm" piece is what pushes the wall out and back.
|Close-up of the corridor with the frame of the secret door opening installed in the "T" section of the main corridor.|
|Same piece, but with the secret wall installed - ready to be UNLEASHED!|
|Same piece again showing the wall partially extended with the pushing "arm" behind it.|
Now to get that wall extension thingie electronicized (my new word)!! Inside the extended corridor section, I glued down a small, flat Lego plate on which a Lego motor was mounted. The motor is controlled by a motor driver circuit that turns a worm gear to extend the DF "arm" which, therefore, extends the secret wall.
|The Lego motor (inside the DF piece) with the worm gear attached. The motor|
driver circuit is also shown with some wires attached.
When the worm gear spins, it moves the "arm" back and forth. I glued a magnet on the "arm" so that when it moves near a small reed switch, the switch closes and the motor reverses direction causing the wall to move back to the original "start" position.
There's a pushbutton switch mounted on the back to trigger the whole mechanism. A slide switch lets the DM control how far the wall travels outward before retuning (either full extension or half way to avoid hitting any miniatures in its path).
|View of the inside before the motor is installed. The circuitry is mounted inside|
on the left wall and the wires to the reed switches can be seen on the right.
To hide the hardware and electronics, I constructed a lid and back end piece out of resin and painted them to look similar to typical Dwarven Forge passage pieces (or at least as best I could!).
|Top cover to hide the hardware stuff (before being painted).|
|Back end cover showing a pushbutton switch to trigger the trap (top right), a slide switch to choose how far|
the wall extends into the corridor (bottom right), and a plug for the power (bottom left).
I hope you enjoyed this tutorial. Stay tuned. I'm close to finishing a few more projects so there'll be more stuff coming soon.