Abstract: A brake spider for a braking system on over the road trailers. The brake spider is to be welded to a tubular axle of the vehicle and is of composite construction. An inner annular member is formed from a pair of rolled, semi-circular steel plates which are joined end to end to form a circular hub. An outer member is cast from ductile cast iron. The inner member includes apertures disposed about the circumference and extend through the hub such that the cast iron fills the apertures and mechanically interlocks the two members together as a composite of cast iron and steel. Because the inner hub portion is steel, it can readily be welded to the vehicle axle. A method of casting the spider of this construction is disclosed including an alternative which uses hollow tubular steel, pierced to form apertures, and sliced to provide the circular inner member.