Alethiometer Prop Build – His Dark Materials BBC

Having finished watching Series 3 at Christmas time ’22, I remembered just how much I liked the Alethiometer prop from the BBC adaptation of the His Dark Materials book series.

This incarnation of the Alethiometer was brought into existence by Michael van Kesteren. I really like the idea he has of the Alethiometer being a tool, and how he thinks about props and how the devices he designs would be used and even taken apart and cleaned.

In preparation for trying to make one, I internet stalked Michael and the production to try and find all I could about the Alethiometer prop. This allowed me to start piecing together an understanding of the device.

With reference screenshots and other information on hand, I started a new parametric design in Autodesk Fusion 360. When trying to re-create a prop I find that using parameters allows me to adjust my design easily if halfway through I find something that lets me know the prop is actually twice as big as I thought.

At the time of writing I’ve been away from this design for a long time. In using my DIY CNC machine to try and cut the brass case, I found it had become very inaccurate and started designing and building a new one. I’m still only about 50% the way through the design. I’m pretty sure I can fabricate the brass case after some experimentation with soft and silver soldering. The cases in the photos below required quite a bit of clean-up on a belt sander to look good and left them very dimensionally inaccurate.