He worked as an assistant to the sculptors Charles Niehaus, Olin Warner, and Daniel Chester French before opening his studio in 1904.

[3] His steadiest income was derived from the sale of small bronze reproductions of his larger works, such as Descending Night, originally commissioned for the Panama–Pacific International Exposition, San Francisco, 1915.

He became the sculptor of choice for the architecture firm McKim, Mead, and White and designed sculpture for their Manhattan Municipal Building, Madison Square Presbyterian Church (completed 1906 and demolished 1919), Prison Ship Martyrs' Monument, and Pennsylvania Railroad Station (completed 1910 and demolished 1963), all in New York City.

[7] Elsewhere he created the dramatic frieze on the Elks National Veterans Memorial in Chicago and executed sculpture for the Post Office Department Building, the Jefferson Memorial, and the interior of the U.S. Supreme Court, all in Washington, D.C. Weinman's non-architectural works include the Macomb and the Maybury monuments in Detroit.

[9] Weinman collaborated with Polish American sculptor Joseph Kiselewski to create a sculpture on the Bronx County Court House in New York City in the early 1930s.

[10] Weinman was one of 250 sculptors who exhibited at the 3rd Sculpture International held at the Philadelphia Museum of Art in the summer of 1949.

His figures typically wear classical drapery, but there is a fluidity found in his work that is a harbinger of the Art Deco style that was to follow him.