Substrate Technology
+1 (815) 941-4800
+1 (815) 941-4600 (fax)
1384 Bungalow Rd.
Morris, Illinois, U.S.A.

I have scratches everywhere in my polished concrete! Why?

There are many possible reasons for this to happen. Here are a few possible causes:

1: Poor Execution of the Work

In many cases the operators of the machines have either gone too fast for the tools to properly process the surface of the concrete; or, in other cases, they may have completely missed spots of the floor during different phases of the polishing process. Work discipline during concrete polishing is of huge importance because for the surface of the polished to look consistent and scratch free, the whole surface must be processed equally by each grit of the process.

Another common error during execution is not cleaning the floor between the polishing steps (vacuuming or wet scrubbing) and not keeping the area closed to other traffic. Forgetting either of these requirements can lead to the same condition ”“ contamination!

2: Diamond Quality

Depending on the supplier of the tools, there is the possibility that the tools are mislabeled or made under conditions of low or no quality control. One possible problem that can occur during manufacturing is contamination of the diamond products by reusing molds or presses that have residues from other diamonds being made.

You can imagine the problem that could occur if a 30 grit diamond crystal gets into the mixture of a 200 grit tool. Diamond manufacturing is an art and not all manufacturers are created equal and none are held to any quality standard by any regulating body whatsoever.

For this reason, consumers are encouraged to do their research before buying that next “Super Terrific Happy Pad” that will “ALWAYS” work. Any reputable supplier will connect you with references of the product’s use and results.

3: Improper Application or Machine for Tool Purpose

A. Using a diamond tool made for concrete on marble is like using a wire brush to clean your fingernails! It will do the job but not without doing some damage. Many diamond manufacturers tell customers that their tools can be used on concrete, marble, and terrazzo surfaces. There is no way this is possible since the chemistry required of the tools for these varying surfaces must be different if the highest possible result is to be achieved for each. This is not my opinion, but is a fact.

B. Another problem for improper tools for a given purpose could be using the wrong bond of diamond tool. Generally speaking, hard concrete needs soft bonded tools and vice versa. It is not really this simple, but the philosophy is generally correct and commonly accepted by all quality diamond manufacturers.

C. Finally, the machine chosen to run the tool must have been considered by the manufacturer when the tool was made. As an example, a tool that is made to perform on a rotary machine with head pressure of 450 pounds (200kg) and 350RPM, can never be expected to perform the same on a machine of half the weight and half the speed. The machine and the tools must be made to work together if predictable results are possible. The best way to fix scratches in your final floor is to not allow conditions for them to be created.

In advance of any project commencement, you need to make sure that:

  • Your diamond supplier can be trusted and has references of tool success on real projects.
  • The tools are made to do the work intended on the machines that will be used.
  • Your work team is fully trained to use the machines and tools properly.

© Substrate Technology, Inc.

The above is a general guideline for why scratches most frequently occur or appear in a polished floor surface. For any clarification of the above or to discuss your unique situation, please do not hesitate to contact STI or any of its authorized dealers for more help and advice. We are all here to supply you solutions that save you time and make you money.