1989 Supercar Concept

Between the V6 Suzuki Coupe and SR1 Speedster projects I produced this one fifth scale concept model for a New Zealand designed Supercar.  I was initially warming to the idea of building a full size Ferrari F40 replica, but decided to look at doing an original design of my own instead.  However, in the ensuing time I ended up collaborating with Fred Onrust to design and construct the SR1 Speedster. (So many ideas. . . so little time!)

The Supercar concept came about through reflecting on New Zealand’s strong motorsport history and the fact that we were also world leaders in yacht and boat-building, so why not a New Zealand designed and manufactured niche market car?  Of course, since that time, the ‘Hulme F1’ supercar project came into being.

To create the concept model, I decided to sculpt it using potters clay, from which I could take a mould to produce a fibreglass shell.  Sculpting in clay was a new, but enjoyable, process for me.  To reduce the amount of clay required, I first made a basic wooden form or plug which had a number of staple nails knocked into it for the clay to key onto.  I fabricated a large sheetmetal tub so I could suspend the finished clay model upside-down into it.  It was then a matter of mixing and pouring a 2-pot urethane compound into the tub to form the mould around the clay.  The tub was lined with plastic to allow the mould, complete with clay model, to be removed from the tub.  The flexible mould could then be peeled off the clay.  By that stage the clay model had done its job and was destroyed in the process.  By placing the mould back in the tub (after cleaning it up) it ensured the mould returned to its correct shape, without any distortion.

The fibreglass shell was then laid up in the mould, before being removed, trimmed and prepared for spray painting and detailing with an airbrush.  The basic form of the wheels was also produced in a urethane mould, taken from a machined pattern, but these were cast in resin using micro-sphere fillers to pad out the volume and reduce excessive heat during the casting process.  The cosmetic holes were machined into the wheels later.

I also produced a one fifth scale model of a proposed chassis design, created from balsa wood (for the main monocoque and rear sub-frame), polystyrene (for a basic motor arrangement) and formed aluminium rod for the upper cage structure.  My thoughts at the time were to use aluminium honeycomb sheet for the main monocoque, but it could have utilised carbon fibre as an option.  It was mainly a styling exercise, but a number of engine and gearbox configurations could have been considered.

It was quite a fun project from start to finish, and below are a few photos of the finished model, and the processes involved.