He was known for his gritty, social realist works depicting urban working-class scenes of New York City and New Jersey.
By age 14, he was studying in Orange, New Jersey with August Schwabe, who introduced Grabach to the Newark Sketch Club.
Grabach continued to paint and draw in his spare time, and he enrolled at the Art Students League of New York where, commuting from New Jersey, he took night classes, studying with Kenyon Cox, Frank V. DuMond, and George Bridgman.
Although he continued to work as a silverware designer — for the firm Rogers, Lunt and Bowlen — his primary interest became his art.
During this time, he painted — in a style not unlike that of John Twachtman’s — several impressionistic winter landscapes of the Connecticut River and New England countryside.
Returning to New Jersey in 1915, Grabach aggressively strove to increase his visibility in art circles by exhibiting widely.
[4] During his daily trips into the city, he became fascinated with the “washdays” of Tuesdays when tenement apartment dwellers strung their laundry on lines from buildings and trees.
Notable works of this period, which encompass aspects of Americanism, social relevance, contemporariness, and visual stimulation, include the paintings Wash Day in Spring (1921) and East Side, New York (1924).
As the 1920s waned and the Great Depression unfolded, Grabach’s breezy, decorative urban scenes began to evolve.
[5] Increasingly concerned by social conditions, his paintings became more melancholy and political, often featuring a somber palette of grays, dark greens, browns, black, and muted reds.
In 1939, Grabach's horse race painting, Taking the Hurdles (c. 1938), was accepted for display at the IBM pavilion at the World's Fair in New York.
Becoming more insular he turned to the Munich School of the nineteenth century for inspiration, drifting away from the art circles of New York and elsewhere.
In 1932, due to the financial hardships of the Great Depression, Grabach accepted a position teaching life-drawing classing at the Newark School of Fine and Industrial Art.