CHICAGO -- Bean there, not done yet.

Plans to complete Millennium Park's Cloud Gate sculpture -- popularly known as the Bean -- by Memorial Day have stalled because buffing the seams of the stainless steel sculpture is taking longer than expected.

The city plans to partially unveil the sculpture on Friday and the tent covering the rest of it will be removed gradually as sections are polished, officials said.

The 110-ton stainless steel sculpture has been hidden from the public's view since January so workers can polish and grind the seams in its 168 plates to a mirror-like finish.

The delay "will allow us to bring the finish on the sculpture to the 'absolute perfection' that it needs," said the work's sculptor Anish Kapoor.

The sculpture's north end -- or about 20 percent of its length -- will be exposed to the public on Friday.

During the work, visitors will be able to watch through clear plastic windows as crews polish the Bean. Some workers will be suspended from harnesses and others will lie on their backs polishing the sculpture's lower portions.