Once cement is poured to form a sidewalk, porch, or other concrete surface, trowels are used to smooth and level the cement as it dries. On small concrete surfaces, hand trowels are used, but trowel machines exist to finish larger surfaces of concrete slab. These trowel machines are also referred to as power trowels, power floats, and helicopters. There are two types of trowel machines --- those that are walked behind and pushed, and those that are ridden.
Choose The Right Type
To use a trowel machine correctly, it is essential to choose the right machine. Walk-behind power trowels are less expensive and easier to transport than riding trowels, because they weigh less. Another advantage is that they allow the operator to see how the concrete is being finished so that mistakes can be seen right away. A disadvantage is that they require considerable strength to push, and they take longer to use than riding ones. Riding power trowels are easy and comfortable to use; little effort is required to operate one, and they work faster than walk-behind trowel machines. Downsides are that they cost more and are cumbersome to transport. It also is easy to overlook defects in the cement when using a riding trowel machine because the operator's attention is focused on what is ahead as he drives the machine rather than the actual concrete that is being finished.
If possible, pour the concrete on a day that is cool but humid. Of course, this is not possible in some climates, but hot, dry weather causes the concrete to dry out before it has the time to cure properly. You should also make sure there is no rain in the forecast; if there is, reschedule your project for another day.
Turn on the machine to make sure it is working properly before the concrete is poured and you need to use it. Read the instruction manual in advance. Check the levels of oil, water, and gasoline in the machine. Gather all your supplies. Nothing can ruin a project like having the cement dry while you scramble to get the machine to work or figure out how to use it.
Timing is Everything
Finding the right time to begin finishing the concrete with a trowel machine requires patience and diligence. Start using the machine when the concrete is dry enough that you hardly leave a print when you step on it; if you sink more than a quarter of an inch it is still too wet. If you push the concrete with your fingers and feel it getting firm, it is time to start the machine.
Use a Float Pan
A float pan, also called a pan float, is a large metal disk with an edge that curves upward, and clips that allow for it to be attached to a power trowel. Attach the float pan to the machine, and go over the floor once before using the machine on the floor directly. Doing this will level the floor and get the concrete ready for the actual finishing.