Monday, July 20, 2009

Rally Fighter Composites

The word of the day at Local Motors is composites. But not composites in general, composites on the Rally Fighter.


But first a definition of composites:
Composites are materials made from two or more constituent materials with different physical or chemical properties which remain separate and distinct on a macroscopic level within the finished structure. What a composite is composed of depends on the properties and characteristics that are desired. Ideally the "weaknesses" of one are canceled out by the "strengths" of another producing a better material than what the two are on their own.

There are two different composite materials being used on the
Rally Fighter. The first is fiberglass we will create ourselves and the second is a thermoplastic called Fiberforge made by the Fiberforge company.

The body panels on the
Rally Fighter are going to be fiberglass, and the rear fenders and bumper cover are going to be Fiberforge (the dark, almost black material in the rear of the car). Fiberglass:
Fiberglass is made of a glass fiber fabric placed in an open mold and then saturated with a wet resin by pouring it over the fabric and working it into the fabric and mold. The mold is then left so that the resin will cure. Once cured the piece can then be trimmed and removed from the mold.

Fiberforge:


Fiberforge is a fiber reinforced thermoplastic which is slightly like fiberglass, but is much stronger, modern, and easier to create because of the advance automated process.

Fiberforge thermoplastic advanced composites compared to other materials:
* 60% lighter and 600% stiffer than steel

* 30% lighter than aluminum
* 200% tougher than thermoset composites

* 500% stiffer than injection molded plastics

* 60% less scrap during production than sheet goods



Check out the following video of Dave Riha (one of LM's Engineer) explaining the use of fiberglass and Fiberforge on the Rally Fighter.


Also, tonight at midnight is the end of submissions for the Roof Mounted Light Bar Engineering Competition! Come check out the submissions. Vote on the best design!
Tell us what you think!