Furze Platt Greenpower Racing

Pictures showing (left) the bubble cooling in the open oven.

Right, Miles removing the bubble from the backing sheet.

The bubble and body being tried on the chassis

                                                          bottom  The finished body

The whole thing was then heated for 3 hours to 100 Celsius. Air was then blown in between the plastic and the MDF backing and the bubble formed through the mould,  when it reached the correct size it was then allowed to cool.  The air was fed from a compressor to give the volume required and to avoid chilling the plastic it was passed through a copper coil inside the oven to warm the air up before it went into the mould.   It needed over 300 litres of air to blow the bubble.   

The bubble formed beautifully and we then let it cool for several hours before it was moved, at this point it was noticed that it had collapsed at the bottom edge where the plastic was inside the hot MDF.  The reason for this was a small air leak and the hot MDF keeping the plastic soft so as the pressure fell inside the bubble it collapsed about an inch. We simply reheated the bubble and blew it up again, then let it cool but this time kept adding puffs of air until it had cooled down enough for the plastic to hold its shape.  

The bubble was then glued to the light weight plywood body which was painted and graphics added by Fine Signs in Cookham. 

The wiring was tidied up and the over current  warning device was fitted.  

The car was now ready for its first try in competition.

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Last modified: 08/06/09