Table of Contents
How do you make concrete floats?
The typical concrete mix designer for use as a building material is sand, aggregate stone and cement mixed with water. In place of gravel or sand, mix in fine glass beads. The beads are strong but much lighter than sand and stone. The glass beads are about 10% the density of water which helps the concrete float.
How long do you wait to bull float concrete?
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.
Can you bull float concrete too much?
If you can’t reach the entire slab from the edges with a darby, rent a bull float and handle to use instead. Two passes over the surface with the darby are enough. Overworking the concrete will draw too much cement and fine sand to the top and create a weak surface.
Can you just bull float concrete?
A bull float is used to level and smooth freshly poured concrete. Concrete used for visible projects, such as driveways, patios and sidewalks, often requires finishing. A bull float is a tool used for finishing concrete.
How many times do you float concrete?
Push the bull float in one direction only across the concrete, keeping its front edge slightly above the surface by raising or lowering the handle. Two or three times is enough. Don’t overwork the concrete or you’ll weaken it by drawing too much sand and cement to the surface.
What is the difference between a Fresno and a bull float?
What it is: The fresno may look similar to the bull float, but its blade is made of tempered or “blue” steel. The fresno should only be used following the bull float. Purpose: The fresno is applied after the bull float to better seal the surface of the slab.
Whats the best bull float?
The 7 Best Bull Floats 2020 # Product 1 Bon Tool 12-946 Rock N Roll Adjustable Bracket for Fresno Trowel and Bull Float Check Price Now 2 Qlt By Marshalltown Concrete Bull Float 48″ With Rock It 2.0 Bracket Check Price Now 3 Qlt By Marshalltown Concrete Bull Float 48″ X 8″ Magnesium Check Price Now.
When should you Powerfloat?
A rough guide for considering when to begin power floating is when walking on the surface leaves indentations of 3-4 mm. If the concrete is too wet the machine will tear up the surface, and if it is too dry, it will not be possible to trim high spots or fill low spots effectively.
What is the purpose of troweling concrete?
With every concrete pour troweling is important, because it allows the concrete to continue the process of finishing the concrete and squeezing residual water out of the concrete. Removing any excess water out of the concrete decreases the chances of the concrete cracking.
What may occur if a slab is floated too soon?
More often, premature finishing or improper first (bull floating) or second floating results in trapping rising bleed water and air below the top surface of the concrete (Image 2). When this occurs, the resulting weak or soft zone below the surface causes the top surface of the concrete to flake or scale off.
How do you edge concrete after it dries?
These are the 4 steps in how to smooth concrete after it dries: Remove all imperfections on the surface. Vacuum up all debris and apply the adherent. Apply a new layer of concrete. Sand the surface and wash the concrete. Apply a layer of vitrifier to protect the concrete.
What happens if you overwork concrete?
Never overwork or over finish the surface of any exposed concrete slab. This brings too much fine material to the surface, works out the designed air entrainment*, and will weaken the surface of the slab leaving the top of slab more vulnerable to freeze/thaw damage and sheet scaling*.
What kind of cement is smooth?
QUIKRETE® Architectural Finish (No. 1220-55) is a polymer modified, Portland cement based repair material designed to provide a smooth finish to tilt-up wall panels, precast or poured concrete, and masonry surfaces.
Why does magnesium float on concrete?
Magnesium smooths the surface of fresh concrete and opens the pores for proper evaporation, all without pulling the surface like a wood or resin tool. Extruded floats are made by pushing molten magnesium through a die (think Play-Doh), so the floats are the same profile from end to end.
What is a bull float made of?
Bull Floats are made of Wood, Aluminum, or Magnesium. Darbies are made of wood and Magnesium. Wood Darbies and Bull Floats are used on slab that are not air-entrained or slab that have slumps of less than 4”.
What happens if you dont trowel concrete?
If you haven’t done this before or only done it, a few times you are likely to make two mistakes; troweling too soon and troweling too much. Both of these have the effect of pulling fines and water to the surface. This can lead to a weakened surface, tiny cracks, and a white dusty surface.
What is the difference between a float and a trowel?
Purpose: Used after floating to produce a smooth, hard, dense slab surface. What’s available: Steel trowels look similar to hand floats, except the blades are thinner and the handles are open rather than closed. The key difference among tools is the type of steel used for the blade.
How long before you can walk on concrete?
Please keep vehicles, children, pets, and yourself off of your newly poured concrete for the next 24 hours. After 24 hours, you can walk on your newly poured concrete, but avoid dragging your feet, ‘doing the twist’, or allowing your pets to walk on it as their claws can scuff the concrete.
Why is it called a bull float?
Probably takes its name from the definition of bull—to make one’s way with driving force (Webster’s New World Dictionary). Spend a few minutes on a hot day smoothing concrete with a bull float, and you’ll get the idea.
What is a Darby float?
A darby is a long, flat tool used to smooth in plastering and rendering. It can also be used on concrete floors. It consists of two handles on a flat plate with slightly lipped edges. A darby is similar to a float, except larger. Primarily used in the final stages of wall and floor coatings, a darby is used to smooth.
