Here's a quick sketch of what's in the workshop at the moment. It's the test-rig that will be connected to the biggest rocket ever fired in Britain. The huge tank will be filled with HTP and pumped into the rocket by the Cosworth formula 1 engine.
I did the sketch in pen, then photographed it and added the colour with the iPad. Works pretty well as a process - saves booting up the old desktop and scanner - I'll be doing it again.