Systems and methods for manufacturing articles of footwear including a sole structure

A method of forming a cushioning element, the method comprising:

• placing a first sheet adjacent to an outer surface of a first mold portion, the first mold portion including a first mold cavity;
• pressing a portion of the first sheet into the first mold portion and into the first mold cavity with a forming tool, wherein at least a portion of the forming tool is extended into the first mold cavity, and wherein the forming tool includes a foam material having a compressive strength in a range of from about 90 MPa to about 97 MPa or a service temperature in a range of from about 149° C. to about 204° C.;
• applying negative pressure to the first mold cavity to draw the portion of the first sheet into the first mold cavity;
• after applying negative pressure to the first mold cavity, placing a second sheet adjacent to an outer surface of a second mold portion, the second mold portion including a second mold cavity;
• pressing a portion of the second sheet into the second mold portion and into the second mold cavity;
• applying negative pressure to the second mold cavity to draw the portion of the second sheet into the second mold cavity;
• and
• joining the second sheet to the first sheet to form the cushioning element.