When very large of areas of concrete floor are to be covered with plastic tiles, maximum evenness of the surface is essential, particularly at joints, if undulations in level are not to become visible. This problem can be overcome by: the channel iron side form is to have an internally threaded sleeve welded to it. A threaded shaft fits in turn into this nut and is held vertical by an L-shaped frame of channel iron which can be staked down for rigidity. The height of the side form can then be adjusted with close precision simply by screwing the treaded shaft up or down. The presence of columns, walls and other obstruction always limits the use of a large scale floor finishing equipment and makes tedious hand finishing necessary. A small side-vibrating machine was built in a site workshop that allows mechanized finishing of even the stiffest mixes right up to obstructions. The machine is powered by a small gasoline driven engine mounted on a low trolley which travels over the already finished and hardened surface of the slab. The leading arm of the machine acts as a vibrating screed and the trailing arm as a vibrating steel float. Joined in the base slab of a floor always present a problem when a granolithic, bituminous, or other topping is to be laid over them. For maximum evenness of the topping, it seems best to from the joint with a wood fiber board having a uniform longitudinal sawcut at its center for almost the full width of the board. The top half of the board, when in place in the joint, can easily be ripped out by means of a hook of reinforcing steel. The topping can then be laid across the joint, and be worked down into it, without the risk of surface irregularity. Also discussed are a new strike-off tool, and sanding concrete slabs.