Self-skinning cast components having negative space spars

A method, comprising:

• inserting a mandrel including at least one surface feature into a molding tool;
• injecting a self-skinning foam material composition into the molding tool;
• closing the molding tool for a period of time;
• and
• generating an overvolume pressure within the molding tool as the self-skinning foam material composition expands and cures to form a component having a negative space spar formed by the mandrel during the period of time;
• wherein:
• the self-skinning foam material composition forms an internal skin on an interior surface of the negative space spar of the component upon generation of the overvolume pressure during expansion and curing during the period of time;
• and
• the at least one surface feature of the mandrel forms a corresponding internal surface feature on the internal skin of the interior surface and is configured to structurally strengthen the component.

A component, comprising:

• a self-skinning foam material composition;
• an external skin formed on an exterior surface of the component;
• a negative space spar within the self-skinning foam material composition;
• and
• an internal skin formed by the self-skinning foam material composition on an interior surface of the negative space spar of the component,
• wherein:
• the external skin and the internal skin are formed by the self-skinning foam material composition upon generation of an overvolume pressure;
• and
• the internal skin includes at least one internal surface feature formed by a corresponding surface feature on a mandrel and is configured to structurally strengthen the component.