If you want to polish a concrete slab, apply a fresh epoxy coating, or revitalize it in another way, you need to start with a clean slab, which often requires removing an existing sealant or another type of coating. However, it’s important to weigh the factors surrounding the project to determine how long it will take, what tools are necessary, and any steps you need to take to get a better end result. To help you better understand how to remove Cure & Seal from a concrete slab, watch the video below or read on for more detailed instructions.
Understanding the Project
In this particular case study, we were asked to assist with removing an older coating of Cure and Seal from a 1,000-square-foot concrete slab. This is a water-based acrylic polymer that acts as a liquid membrane to protect the surface and harden the slab. The contractor was planning on using a single disc grinding tool, which may have taken him well over a single day just to remove the coating, but we came in, took stock of the concrete, and came up with a plan to do the job quickly without cutting corners.
Factors That Affect Surface Preparation
It’s important to consider a wide variety of factors that determine the tools you’ll need, the work involved, and the time the task will take. This includes:
- Hardness of the concrete: Grinding a hard slab requires soft bond diamond tooling, a powerful grinder, and more time to complete the task whereas a softer slab may require densifying, harder bond tooling, and more care to avoid chipping or over grinding.
- The coating on the slab: A mastic coating or thick epoxy layer will need more aggressive grinding tools than a thin epoxy or urethane coating. In some cases, a shot blaster may be ideal for removing a thinner coating, especially if the slab needs to be profiled first.
- Condition of the concrete: A bumpy or uneven slab will require additional passes over certain spaces to create a level surface.
In this instance, we were working with a very hard slab that earned a Mohs rating of 7 using a scratch test. Additionally, this was a thin, yet penetrative coating that would require more work to remove, plus the concrete was uneven in places and required additional leveling.
Choosing the Right Tools for the Task
To do this job correctly, we used the Prep/Master Jr. floor grinder. While it’s our smallest concrete grinder, it has the power and performance to tackle difficult jobs in small spaces, making it perfect for this project. We paired it with 30 grit medium bond diamonds from Substrate Technology Inc. and used a light water mist to improve performance while minimizing dust.
Typically, the Prep/Master Jr. profiles a slab at a rate of about 600 square feet per hour, but as we mentioned above, the slab determines the speed, and the hardness, coating, and undulations slowed the process. However, we still completed the preparation in right around three hours while still achieving professional-quality results!
Shop for Surface Preparation Equipment Today
If you’re in need of high-quality surface preparation equipment, we have everything you need to do the job right. Shop our large selection of equipment, tooling, and more, including concrete grinders, or learn more about our products by speaking to a product expert at (815) 472-9711 or by filling out our contact form. We would be happy to educate and guide you any way we’re able to!