Daily Archives: May 20, 2007

Victoria Day weekend

Despite best intentions it all comes down to a mad rush to finish building the car. This drizzly long weekend is all about constructing the axle mounting system. Things to keep in mind are:

-axle alignment

-accounting for any flex in chassis, or eliminating flex

-provisions for axle adjustments

Our car is designed so that the axles are a sub-assembly of the main chassis. Other car designs may have the axles and mounts as integral with the chassis – so the above points may have been taken care of already.

My approach in axle design differs slightly from what is outlined in the “soapbox construction manual” (linked in share box on sidebar) in that I am discounting the need to account for axle flex in the mounting system. There will be some flex in any system, but I theorise that with beefier axle members and pneumatic tires, road shock will be taken up mainly by the tires rather than the axle itself. If you are using solid tires and solid wheels then road shock will be translated almost entirely into axle flex.

Consistent with this approach is our goal to eliminate (or at least reduce) any chassis flex. As a side note, the photo of the Canamera/BC Cancer Agency car shows a very low ground clearance. I am sure the designers have done their homework on the shape and angles of the launch ramp and speed bumps, but it looks close to the limit before grounding out. In their case chassis flex would be quite unfavourable 🙂