The first finishing tool on the slab pushes down rocks and brings the cream to the top of the concrete surface
After pouring the concrete and screeding it level, it is time to begin finishing the slab, in this case, a small driveway addition. A 3-1/2 foot wide magnesium bull float is the first tool to clean up the surface.
In this video, the bull float has been over the surface once, and then the edges have been shaped with a hand edger. The second pass of the bull float is to remove up the lines from the hand edger.
The magnesium blade pushes the aggregate down slightly, which displaces water and slurry causing it to rise. That's why the bull float brings "the cream" to the top.
When you push the bull float away, tilt the front up a little bit. As you pull it back, lift the back slightly. This keeps the surface smooth without digging in by mistake.
If you find a high spot while floating, you can bury the front a little bit and push the hump around to even it out.
David recommends buying a used bull float rather than a new one because a broken in bull float is a little smoother to operate. The main thing to look for when buying a used bull float is whether the float is still straight without many dings in it.