After college, he went to work for Nickles Machine Corporation in Ponca City, a business started in 1918 by his grandfather, Clair Nickles. He became the company's vice president and general manager. He also served in the Oklahoma National Guard from 1970 until 1976. A formative experience was the distress his family suffered following the death of his father, Robert, in 1961, when Nickles was twelve years old. The family had to sell off part of the family business to raise cash to pay the required estate tax.