Mack was born in Minneapolis, to a family that had never been directly involved in art. However, he was creating and selling oil portraits by the time he was in high school. At only 17 years old, he was already employed as a draftsman for a company making bronze dedication tablets. There, a crucial moment occurred which would change his life forever. Portraits are the most difficult image to create in relief. When a poor quality relief portrait for a memorial tablet created by another artist was submitted to the company for approval, Mack thought he could do a better job. He gave it a try and it was instantly accepted. He immediately quit his job and began a career as a commissioned relief sculptor.

Deeper than Bas-Relief and more unique than traditional sculptures, Mack's ingenious creations have created legions of collectors and fans around the world. Besides creating hundreds of works in traditional cast bronze, he has also gained experience with more modern substances, including resins, urethanes, epoxies, silicones, and acrylics. Working in different materials and trying new methods, Mack has gained increasing confidence in his abilities.

Mack is a colorful character as well, wearing a fresh red rose bud on his lapel every day. Though he will not reveal the personal reason why he began the practice some years ago, the red rose has become a symbolic trademark. Presenting them at gallery openings, he has become the largest non-commercial buyer of roses in the world, requiring tens of thousands of them each year.