Pigpen Cipher Decoder Tablet for Escape Rooms

The Pigpen cipher (also known as Masonic cipher, Freemason's cipher, or tic-tac-toe cipher) is a simple substitution cipher which exchanges letters for geometric symbols. There are numerous ways to assign the letter to the grid but this is the most common. Each square inside the grid is referred to a "pen" and the dots are called "pigs" hence the name Pigpen. It is has been around for hundreds of years with evidence of its use as early as the Crusades and is still very popular today with escape rooms.

Tool:

xTool S1 40W Laser Engraver

Software:

xTool Creative Space

Material:

12" sheet of 3mm basswood plywood

clearcoat

Create the grid by drawing four 4"x1/8" rectangles arranged like a tic-tac-toe game. Use the "Combine" tools in Creative Space to unite the rectangles into one object. Make a copy of this grid and place it adjacent to the original. Add 1/8" circles for the pigs as shown in the pictures. Use the "Combine" tools again to unite the circles and grid into one object.

Add letters A-I in the pens of the first grid. Add letters J-R in the pens of the second grid. I used Amita font with 70 pt size.

Create the X by drawing two 4"x1/8" rectangles. Use the "Combine" tools in creative space to unite the rectangles into one object. Make a copy of this X and add 1/8" circles for the pigs as shown in the pictures. Use the "Combine" tool again to unite the circles and X into one object.

Add letters S-V in the pens of the first X. Add letters W-Z in the pens of the second X. I used Amita font with 70 pt size.

Add text for a header. I used the Amita font with a 95 pt. size

I added a border from Creative Space's stock shapes and used the "Outline" tool to create a 0.25" offset.

Set the grids, Xs, text, and border to engrave and the border offset to cut.

Lightly sand any burn marks on the panel, wipe down and apply a clearcoat.

The geometric symbols used in the cipher are the pens of the grids and Xs. Use the tablet to determine which letters correspond to the appropriate symbol.

The main way we use a substitution cipher in our escape rooms is by displaying a coded phrase somewhere in the room. Sometime, we will place the decoder tablet in plain sight in the room. Other times, we will require the participants to complete a task before they can get the decoder. Once decoded, this phrase will give them a clue to where they can find a hidden key to a padlock like in the example above.