Ceiling concrete finishing - GIF

Ceiling concrete finishing.

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Previously:

Filling a concrete mixer from a distance - GIF
Forming concrete stair treads - GIF
Four man wet concrete object retrieval technique - GIF
Making concrete door moldings - GIF
Pouring a concrete roof - GIF

So... they lined the forms with plastic water than using from oil. Perhaps that would allow them to apply a decorative coating for a finished surface?