Review on OCR Concrete Diamond Grinding Grinder by Michael Barry

I bought two 4.5" OCR diamond grinding wheels for $10 (yellow) and used them with a RYOBI AG4031G 4-1/2" angle grinder for $35 US dollars used. I argued that my concrete grinding project would destroy both tools, and I bought Chinaseum's cheapest disposable tools for the job. These OCR brand grinding wheels worked just the way I needed them to. I was expecting bad wear and tear so I bought two. I covered 1000 sq ft of 4000psi glass fiber reinforced concrete with just one wheel - the OCR wheel had 3.3mm of usable material left from the original 4.1mm. The surface feels perfectly smooth with no burrs. I attribute the excellent results to the quality of the $10 OCR cup wheel and my technique of using the $35 RYOBI angle grinder. Wet sanding offers two important advantages: it reduces the amount of dust to almost zero and significantly reduces wear on the sanding pad! This $10 tool lasts surprisingly long when used under constant steam. Conclusion: I will probably never need a 4.5" OCR diamond grinding wheel again. I am extremely pleased with the quality and performance of this relatively inexpensive tool and would heartily recommend it for concrete grinding projects. Added bonus: Chinglish! Who doesn't love Chinglish !