Well the concept is simple enough - grab a heap of steel tubing and follow Ron Champion’s book to build a space-frame chassis. The reality is that the process is far from simple and there are many decisions to be made along the way and problems to overcome.
First step was to decide on the mechanical components that I was going to use as they determine a lot of the design criteria.
I purchased a complete 2006 Mazda MX5 as my donor vehicle and a selection of steel tubing, I was then ready to begin the process.
Second step was to rethink the frame design as Ron Champion’s original design is not strong enough to meet the Australian Design Rules and requires additional bracing and triangulation.
There are many different ideas floating around on how to build the best Locost, so I don’t think that any two cars are really identical. I obtained a great set of detailed plans from Formula Motor Sport in Queensland and incorporated many of their ideas into my chassis. Unfortunately they removed their very realistically priced Locost chassis plans from sale due to the high cost of public liability and professional indemnity insurance.
The original “book” design is also a bit on the narrow side, therefore, like many other builders, I added extra width (130mm in my case), I also extended the length by 100mm in the cabin, 50mm in the footwells and 50mm in the engine bay plus 25mm higher from the scuttle forward and increased the size of the rear “boot” area. My Locost will be very individual and designed to suit my needs.
First up I built a solid timber table with steel legs to provide the level surface required for the space-frame construction, which also gave me a good chance to practice my cutting and welding skills before launching into the serious construction stuff. The top was 20mm chipboard with 90mm x 30mm pine supports glued on the long edges and a steel tube frame underneath.
I don’t plan on detailing the build process in this section as I believe that the many photos on this site will best describe how it developed. I have included some notes with the photos where appropriate. So take a look at the photo albums and follow my project as it grows ...............