SYDNEY Harbour is about to become a "huge bathtub", complete with a five storey-high Rubber Duck, all in the name of art.

One of the quirky highlights of Sydney Festival 2013 will be Dutch artist Florentijn Hofman's Rubber Duck, set to enter Cockle Bay as part of the Day One - The Arrival on Saturday afternoon.

The Rubber Duck enjoyed a dress rehearsal early Thursday morning ahead of its official launch.



Sydney Festival production manager Mick Jessop has been overseeing construction of the giant toy-like sculpture for the past nine months.



The Rubber Duck - made of a PVC material similar to jumping castles - was constructed in New Zealand by a company that specialises in sewing stadium rooftops and large sails.



"He's about 15m high by 15m wide and he's about 18m long," Mr Jessop said of the duck.



"It took three people three weeks to sew it - it's about 6km of stitching.



"Twenty-five to 30 minutes is all it takes (to inflate), that's using four blowers."



Spectators won't notice it from the shore, but the Rubber Duck, weighing in at 500kg, will be sitting on a 10-tonne barge, hidden by the surface of the water, to ensure it doesn't take flight in the event of high winds.



Just getting the duck into the harbour involves several tug boats, the opening of Pyrmont Bridge, plus a break in the monorail service.



"I got to go inside it and see how it goes up and down - it's like being inside a big yellow bubble," Mr Jessop said.



"We're using these beautiful heritage-restored tugs, they're going to push in the duck, these tugs are going to be completely dwarfed by the duck.



"It's going to look like a huge bathtub."

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