The equatorial sundial is one of the tradition sundial designs. The gnomon, the piece that casts a shadow is lined up with the axis of spin of the earth. To do this the whole assembly needs to be able to tilt back and forth depending on where on earth the sundial is used.
In the picture on the right you may be able to make out the angle is set to just over 50 degrees, this is the latitute where we are.
Once the angle is set up right it is simply a matter of lining up the sundial on the North/South line and waiting for the sun to come out. Works a treat! This prototype had the time spot on when the sun peeped through the clouds this afternoon.
Layout and colour next. A subscriber exclusive I think.