Summary
Concrete floors require preparation before applying a paint, high-performance coating system, stain or a concrete sealer. The preparation usually involves cleaning the surface to remove oil and other unwanted contaminants then “profiling” the concrete by etching with acid or by mechanical abrasion.
If the concrete does not have heavy oil contamination, Great Lakes Laboratories Clean ‘n Etch will provide both the cleaning and the profiling in one operation.
For concrete with heavy concentrations of oil or other contaminants, clean the surface first with Great Lakes Laboratories All Purpose Prepaint Degreaser and then apply the Clean ‘n Etch for final cleaning and profiling of the surface.
New concrete may have been treated with a “cure & seal” to slow water loss during curing. Clean ‘n Etch will remove many of these compounds. Test by applying a drop of Clean ‘n Etch to the surface. If small bubbles appear, the Clean ‘n Etch is reacting with the cure & seal and will remove it. If no bubbles appear, Clean ‘n Etch will not remove it.
If the concrete has been steel-trowelled, the surface will be very smooth. This finishing technique works fine cement particles to the surface creating a very hard, dense finish. Steel-trowelled floors require a 1:1 mixture of Clean ‘n Etch with water and may require multiple applications to achieve the desired profile.
Equipment
- Plastic sprinkling can or 3 gal. plastic garden sprayer
- Push broom with natural or synthetic bristles
- Water for rinsing
Usage tips
- Work in 10’x10′ sections. Working in larger sections may prevent rinsing before the solution begins to dry resulting in white, powdery residue.
- If available, use a squeegee or wet-dry vac to remove the etching solution before rinsing.
- Do not apply the solution with a mop. Mopping smears the solution over the surface and does not supply enough solution uniformly for effective etching.
Optional Equipment Usage tips – Continued
- We do not recommend using a scrubbing machine as the brush or pad may be contaminated and may not provide sufficient agitation of the surface.
- Long-handled squeegee
- Wet-dry vacuum
Method
- Dampen a 10’x10′ section of the floor. A little water on the surface helps activate the etching solution.
- Apply the Clean ‘n Etch solution so that a uniform film covers the section to be treated.
- Allow 5 minutes contact time.
- Using the pushbroom scrub the solution into the floor working in one direction and then scrub across the surface at 90° to the first direction.
- Allow the solution to remain on the surface for an additional 2 – 5 minutes.
- If available, use a squeegee to remove the etching solution before rinsing. Otherwise, rinse using plenty of water. Scrub the surface while rinsing to insure complete removal of the etching solution.
- Move to an adjacent area and repeat the process.
Troubleshooting
- A white haze, white streaks or white, powdery dust on the surface after drying is caused by waiting too long before rinsing or by inadequate rinsing. The white powder is a combination of cement particles released from the surface and a precipitate byproduct of the etching reaction, insoluble calcium phosphate.
Remove as much as possible by sweeping, scraping or vacuuming. A light dusting typically will not show through a clear coating and will not affect adhesion.
- Look for areas on the treated surface that are darker or glossier than the rest of the treated surface. Water beading or breaking on these areas signals that the surface is not ready for coating application and should be treated again.
- If water soaks into the treated surface without beading or breaking and the surface has the degree of profile specified by the coating manufacturer, the surface is ready for coating application.
- Neutralizing the surface after etching is not required because Clean ‘n Etch is self-neutralizing. Once the bubbling stops, the remaining mildly acidic solution is easily removed by thorough rinsing.
For Technical Assistance Call:
1-800-888-1105