After three days suspended above downtown Minneapolis, Andy Saczynski is now an official “walldog.”

Since Tuesday, the Florida-based artist has been hand-painting a billboard atop 930 Hennepin Av. S. for Immaculate Baking Co., a brand of scratch baking mixes and ingredients owned by General Mills.

The mural depicts the Minneapolis skyline in a colorful and clever way, although the 36-year-old mixed-media artist admits this is his first billboard — and that he’s afraid of heights. Or, he was afraid of heights.

“The first day I was a little shaky up there,” he said. “After two hours up there, I got pretty comfortable. I got my sea legs, I guess you could say.”

These days, billboards are usually digital or large-scale printing jobs. But at midcentury, it wasn’t unusual to see artists (or “walldogs”) scaling big buildings, paintbrushes in tow.

Saczynski’s work will be finished by Friday, and will remain on display throughout the month of August. He said he was approached after two of his works were selected for Immaculate Baking’s cookie and flour packaging, although his specialty is “assemblage art” using acrylics and found and recycled objects.

The billboard is intended to celebrate a new line of scratch baking mixes and organic ingredients for Immaculate Baking, which was purchased for an undisclosed amount by Golden Valley-based General Mills in 2013.

The billboard measures 40 feet by 18 feet and rises above the former National Camera Exchange building in the entertainment district. The building has been vacant for a number of years and is being marketed for sale by Neil Friedman of Jordan Realty in Minneapolis.