Hand floats are specialized tools that are used by craftsmen and laborers who work with building materials like plaster and masonry cement. After the material is initially applied with a trowel, the workers will then allow the mixture to harden enough to remain stationary except for on the top surface. At that point, they use hand floats to smooth the application as much as possible in order to give a sleek, professional appearance. The name “float” derives from the way that the tool glides across the surface of the texture being smoothed out, almost as if it were floating on air.
Hand floats are constructed in varying sizes of up to 20 inches (.5 meters) in length and can be found crafted in metal, wood, and hard plastics. It is debatable which size or length is the most appropriate, and it largely depends on the actual task being accomplished; some craftsmen will use a particular hand float for every project while others will rotate through several depending on the overall size of the work area. There are also bull floats, which are most commonly made from magnesium and have handles that extend their overall reach from 4 to 10 feet (1.2 to 3.1 meters). Trowels are not hand floats—a hand float is designed to quickly remove the coarseness across a large area, while a trowel is used for precise finishing that meets professional standards.
When using hand floats on a concrete slab, the overall timing is essential. If a float is used on the surface too soon, the surface is likely to shift and become distorted, but if too much time transpires and the surface is allowed to harden, then a concrete hand float will become all but worthless. The key is for users to begin smoothing the concrete while it is still moist on the surface, but without too much overall give, and if the timing is off, then additional water can be added to the surface once. Many professionals will work in pairs when it comes to finishing with hand floats, especially on larger projects.
When using hand floats on plaster and drywall, the process is very similar. After the mixture is applied to the drywall, a hand float is used to quickly smooth out the plaster before it has a chance to harden. Since plaster sets much more quickly than concrete and can often be more difficult to work with, a hand trowel is often used directly afterward in order to make the overall appearance look seamless.