I was recently pointed to this blog, British Reaction Research, detailing the progress of blogger and rocket engineer, Carl, as he builds a liquid-fueled rocket engine.
Not just your normal amateur liquid rocket engine, Carl is attempting to make an aluminium tube bundled engine. For those not familiar with this construction, the engine is built up of multiple tubes, shaped to achieve the desired coolant velocity and usually brazed together to form the rocket engine.
The latest update delves into the testing process in order to use these tubes in the bundle.
I have been looking into the forces required to break a hypothetical aluminium test piece, in order to come up with a set of dimensions that keeps the pressure needed within acceptably safe limits.
Make sure to follow the British Reaction Research blog as there is a ton of information in there all amateur builders will find very useful, and stay up to date with the latest on the tube bundled engine!