At the end of secondary school a baccalaureate party would be organized where graduating students would be allowed to wreak havoc with water guns, flour, eggs on younger students along with other festivities. I couldn't find a satisfactory water gun at supermarkets so I ended up making my own. There were several things that I wanted in my water gun:

- high capacity with continuous stream (as opposed to a cannon- like design)

- long range

- adjustable debit

- robust

There are many online tutorials making water guns out of PVC piping from the US. Unfortunately I was unable to get my hands on PVC pipes and PVC glue in the EU due to regulations on the PVC additives (environment and toxicity). The only pipes available at local hardware stores here were PP and PE pipes. PP and PE are unreactive and as a result proper chemical bonding agents aren't readily available to consumers. I had to therefore go for a mechanical sealing method. After many tests exploding seals, I eventually found a solution that could withstand up to 2 bars of pressure. 2 bars might not sound like much but achieving this with non pressure rated pipes was very difficult.

I managed to keep the  pipes together by silicone gunning the seals and binding all the pipes together with a steel ribbon under tension. Due to the "O" shape of the tank the steel ribbon would counter the expansion of the resevoir and thus preventing leaks or explosions.