Darbying or bull floating should be done immediately after "screeding", or after the concrete has been tamped if tamping was done.This process should be finished before excess moisture or bleedwater appear on the surface.

The purpose of darbying or bull floating concrete is to level ridges and fill voids left by the screeding operation. It should also slightly embed the coarse aggregate to make subsequent finishing operations easier.

Be careful when using these tools not to close up or seal the surface of the concrete, which may cause blistering or scaling.

Use a bull float for areas too large to reach with a darby, though it may produce a wavier surface.

Floats

Purpose: To level ridges, fill voids, and smooth the surface in preparation for troweling. Floats also can be used to work in dry-shake color hardener. Unlike trowel finishing, floating won't close the surface, which is important at this stage to permit water to bleed out. A float also helps bring paste to the surface by pushing down the coarse aggregate.