After graduating high school in Milwaukee, Dave entered the jewelry trade in Chicago as a stonecutter. In 1939 he met his future wife, a vivacious young woman named Edna Ruth Jaenke, during a fireworks show at Soldier Field. Married in 1940, they moved to Southern California soon afterward. During World War II, Dave built military aircraft at Lockheed Aircraft Company in Burbank, working as a tool and die maker.

Dave and Edna raised four sons - John, Larry, Tim, and Steve - in Tujunga, at the northern edge of Los Angeles. On family excursions, they introduced their sons to the archaeology, history, geology, mineralogy, and architecture of the West.

In the late 1940s Dave returned to jewelry making and founded "Shoup Jewelers" in downtown Tujunga. Dave and Edna fell in love with Hawai'i during their first visits in the 1950s. When Dave was offered a job at a small jewelry company called Maui Divers, the family moved to the islands in 1965.

In 1968 Dave opened his own fine jewelry manufacturing business, "Jewels of the Pacific", on Ena Road in Waikiki. Dave was creative and successful, and built a steady clientele for his custom-made pieces. Many famous and not-so-famous people came to the store to talk with Dave and buy his distinctive work until he closed the shop in the late 1980s. He continued making jewelry at his home workshop in Kahalu'u until a few years ago.

Dave and Edna lived on a Chinese junk at Ala Moana Marina until 1972, when they built a house in Kahalu'u overlooking the sea. Their house has always been a gathering place for their family and friends.

Dave loved traveling and visited the mines of Australia, Sri Lanka, and Brazil in search of gemstones, often with one of his sons. He had a passion for Japanese and Chinese antiques and was an avid reader of history. Dave was generous with his time and expertise, and was a friend and mentor to many young jewelers.