Hubert Massey fresco in Cobo Center nears completion

It sounds totally counter-intuitive. You paint onto wet plaster?

But that, of course, is how frescoes have been crafted from Leonardo da Vinci to Diego Rivera. Hubert Massey’s Cobo Center mural, “Detroit: Crossroad of Innovation,” is no exception, hewing to the ancient, time-consuming technique.

“I actually love the process,” said Massey, beaming. “Frescoes last for thousands of years. They say 60 years after it’s painted, a fresco is 60 years richer in color.”

He peers up at the black-and-white drawing 30 feet tall and 30 feet wide before suggesting that his assistant “fog it up a little” by spraying moisture on the plaster where the 60-year-old Detroiter will paint shortly.

“The wall,” said Massey, who started life as a commercial sign painter, “is really drinking today.”

You’re probably familiar with the artist’s work, whether you realize it or not. Among many other local projects, Massey designed the colorful mosaic on the Bagley-Mexicantown pedestrian bridge, as well as the one on the College for Creative Studies parking structure at Frederick and Brush.

The black-and-white rendering now being painted in Cobo looms on a wall just outside the Grand Riverview Ballroom, and it is a visual explosion of perspective and movement.

The “Spirit of Detroit” rises at right, magically towering over the Ambassador Bridge. A Native American woman points the way to Canada for escaping slaves. Centered at bottom, a woman in dreadlocks spreads her arms wide to join hands with city and suburbs.

As of last week, Massey — who works from 7 a.m. to sunset, unless Cobo’s got a convention — had painted the upper left-hand corner, a fragment of sky with clouds that almost seem to fly off the wall.

But he’s still got four-fifths to go before finishing, he predicts, by early June. Here’s what that will entail, day in and day out:

Massey’s superimposed a grid of thin straight lines, and paints in methodical progression, square by square. But before he can pick up his brush, he’ll trace each square’s design on tracing paper, and perforate the lines he’s just drawn with tiny holes.

“A long time ago they used pins on sticks,” Massey said, “but now they make them using electricity.”

Next, his assistants will apply two wet coats onto the square in question — the first of brownish plaster, and then lime mixed with marble dust on top of that.

Inevitably, of course, this obscures the drawing on the wall.

That’s when the tracing paper gets tacked back over its square, and Massey gently rubs a small bag full of charcoal dust over the perforations, recreating the lines obscured by the plaster.

He then paints black outlines and all necessary shading.

“Once I’ve got the depth and tonality I want in the shading,” Massey said, “then I paint over that with color.”

Any giant fresco based in this city inevitably invites comparison to Diego Rivera’s monumental “Detroit Industry” at the Detroit Institute of Arts.

This is particularly the case with an artist like Massey, who trained in the 1970s with Lucienne Bloch and Stephen Dimitroff, who’d both apprenticed with Rivera.

In comparing their respective styles to Rivera’s, Massey called the Mexican giant’s technique “a little more linear and flatter than mine. That’s his style and the way he did things.”

mhodges@detroitnews.com

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