Building an R1 Powered Seven
A few years ago I got it in my head to build a kit car. After months of searching I came across the Locost concept. In short, quite a few amateur hobbiests around the world have built their own Lotus 7 inspired cars from scratch, following plans available on a variety of Internet sites and published in a book by Ron Champion.
I started gathering parts and finally began building the chassis in July '05. In August '10 the car was titled, licensed and is now street legal. The following blog captures the progress of the build and driving experiences after completion.
I worked on forming the side panels today. In the lotus 7, the sides transition from flat to curved where the sides meet the nose cone. Since I have limited metal working tools, getting the curve without waves was tricky.
I tried a range of things from bending by hand over a curved surface, to rolling over a toy bowling ball (kind of like a one sided English wheel). In the end I took a small piece of a 2x4 and rounded the corners, placed the panel on foam cushions, then pressed and rubbed the 2x4 on the inside of the panel to stetch the metal. This seemed to work the best. The end result wasn't perfect, but not too bad considering the tools I had to work with. I may spend a little more time on the panel, but it's pretty close to being done.
I called to check on the header tubing only to hear it's on back order, not a big deal though since there are plenty of other things to work on.
Yesterday I finished up most of the interior panels. I decided to use 8-32 screws to attach the panels on the tunnel since they will no doubt have to come off in the future. Most of the day was spent drilling and tapping the 106 holes, but who was counting.
Just need to finish trimming and attaching the side panels and the interior will be done.
Today was the first full day working on the car in a while. I finished welding the last pieces to the frame, I think...brackets for the roll bar supports. Also cut and bent the rear interior aluminum panel.
Tube bends for the headers are on order from
http://www.magnumforceracing.com/ubend.asp , thanks to info from Joe Garrison on the Yahoo Locost NA list. I'll work on the remaining interior body panels until they arrive.
I started a job that I've been thinking about (i.e. putting off) for some time, the headers and exhaust. I have the original bike header and was hoping to modify this, but it turns out it's made from titanium and therefore beyond my welding capabilities. So, I'm stuck with building a new header from scratch...
Last night I decided to model the headers in Solidworks in hopes of saving some time cutting and fitting, and hopefully end up with a better result. After about 4 hrs I came to a point where I can say good enough. Each runner is within 1" in length, and I can match the length of the original bike headers by shortening the last straight section. As I fabricate the runners, I should be able to cheat a little bit to more closely match the lengths.
I also finished up the seat belt/harness mounts. Next I'll order the exhaust bends, and work on sheet metal until they arrive.
