[5] He frequented the Uptown Community Workshop, a gathering place for black artists and writers such as Langston Hughes, Richard Wright and Jacob Lawrence.

Starting in 1936, he went to DeWitt Clinton High School in the Bronx, where he worked on the literary magazine The Magpie as a writer and artist along with peer James Baldwin.

From 1940 to 1943, a work scholarship to the Art Students League made it possible for him to study painting with Vaclav Vytlacil and lithography with Will Barnet, who became his friend.

Blackburn was also later able to study at Stanley William Hayter's influential Atelier 17 in New York, an experience that contributed to his desire to open his own print shop.

Among the many artists who have worked with Blackburn at the Printmaking Workshop are Elizabeth Catlett, Charles White, Nadine M. DeLawrence, Vivian Browne, Emma Amos, Otto Neals, Ernst Crichlow, Samella Lewis, John Biggers, Ed Clark, Mavis Pusey, Vincent Dacosta Smith, Camille Billops, Melvin Edwards, Mildred Thompson, Benny Andrews, Betty Blayton, Aminah Robinson, Romare Bearden, Kay Brown, Dinga McCannon, Leonora Carrington, Roy DeCarava, Sue Fuller, Eldzier Cortor, Faith Ringgold, Betye Saar, Faith Wilding and Jack Whitten.

[11] His commitment to sponsoring minority and third-world students and developing community programs profoundly influenced younger printmakers, who seeded similar workshops around the United States and internationally.

[9] He returned to primarily working at the Printmaking Workshop on a full-time basis after a printing accident in 1962, in which a stone by Robert Rauschenberg was broken, shaking Blackburn's confidence.

Smaller selections of the Workshop's prints have been placed with the Schomburg Center for Research in Black Culture and El Museo Del Barrio, New York.

During the 1970s, he participated in a community art space called Communications Village operated by printmaker Benjamin Leroy Wigfall in Kingston, NY.

Blackburn's early work at DeWitt Clinton High School, where classmates included artists Burton Hasen, David Finn and Harold Altman, was exhibited at the Metropolitan Museum in 2009.