When it comes to grinding and polishing concrete, many of you may know that it can be done wet, or dry. But why the option? Is one better than the other?
It is obvious that different circumstances require different actions and decisions, and different people have different preferences; but what factors contribute to those actions, decisions and preferences when it comes to Wet or Dry Concrete Polishing?
This blog is going to take a closer look at each option and discuss when and why they might be used.
THE WET PROCESS
The Wet process is the oldest way of grinding and polishing concrete. Many people prefer the wet process for the simple reason that it has been around the longest and they learned to grind and polish concrete using this method.
The wet process uses water, which is relatively accessible in the geographical locations where that method is preferred.
The water cools the diamond tooling by acting as a lubricant and reducing friction. Depending on the tooling you’re using, this can help extend the life of your tooling by reducing the possibility of melting the resin or having it glaze over. It also helps with the dust by wetting it down. This means that you are protected from breathing in the respirable dust particles, like Silica, that are exposed during the grinding process.
Although using water does help prevent the user from being exposed to large amounts of respirable dust particles, it creates a slurry like paste on the concrete surface which needs to be cleaned up and disposed of appropriately. In some locations and instances, the slurry can be recycled to be used for things like road mix.
There are a few reasons people prefer wet grinding and polishing vs. dry, but there are also a few disadvantages that have caused some concern.
Many feel the large amounts of water used for larger jobs when wet grinding or polishing, can be very wasteful if used in situations where dry grinding is possible. With the rising amount of globalized water issues, it seems like an unnecessary option for many circumstances.
You can’t achieve the same shine with wet polishing as you can with dry, so for situations like decorative flooring, or when you're looking for a high shine finish, it doesn’t make sense to use the wet polishing method.
Additionally, although it does wet down the dust particles so they can’t be inhaled by the user, the slurry that is left over is time consuming to clean up and not always easy to dispose of. As a result, environmental issues are an increasing concern, and efficient disposal of the slurry caused by wet polishing is becoming somewhat of an issue.
THE DRY PROCESS
Grinders and Polishers are now compatible with Dust Extraction Systems that can be attached right to the machine and collect the dust as it’s being made. Appropriate dust extraction systems with certified HEPA filters will ensure that all of the dangerous respirable silica dust is filtered out of the air so it is safe to breathe.
Not only does this ensure a safe work environment but it also cleans as you work, so you have a more even and clean surface for grinding and polishing and it eliminates the extensive cleanup after you’re done. This saves you time and money.
Many agree that the wet process unnecessarily consumes a lot of water, making it an environmental concern. Many opt for the dry process for this reason. Furthermore, you get a much better shine and finish when using the dry process, it’s impossible to get the same finish when using water.
When using a dust extraction system alongside as you grind, not only are you eliminating that aspect of cleanup immediately, but it will be easier to dispose of the dust and debris quickly, efficiently and safely making it a much better option from a business standpoint.
Some claim that if the concrete is super hard it is still best to use the wet method to start, and switch to dry after the first few steps, but many people don’t understand the importance of the appropriate tooling. With the new technology, manufacturers have been able to create tooling for hard concrete that withstands the temperatures and won’t melt or glaze over. If you’ve properly tested the hardness of the concrete and are using the appropriate tooling, you shouldn’t have any issues.
Some believe that the wet process is a lot less expensive and affordable because a dust extraction system is an additional cost to purchase. Firstly, Dust extraction equipment can often be rented to save some money if the initial cost seems to be too high. Secondly, the amount of time and money you’ll save in clean up, will pay for the dust extraction system faster than you may think.
SO WHICH IS BETTER?
The choice between wet and dry grinding and polishing tends to be based on preference. Sometimes people will choose to do a bit of both by starting with wet and switch to dry, but it still won’t turn out quite the same because of the slurry created by wet grinding is composed of abrasive particles which will affect your process, plus you’ll still have to clean up the slurry in-between the grinding and polishing steps, which takes time. So not only will it take more time and effort you won’t end up with the same standard finish.
Technically, with the advancements in tooling technology, there is no longer an advantage to the Wet process. Again, it really is a preference, but most people are moving towards the dry process for various reasons.
The dry process is safer because you don't have the debris, water or slurry on the floor of your workspace which can cause slips and the dry process elimates the dust immediately from the workspace and filters out the toxic respirable particles through the HEPA certified filter in your dust extraction system. It's also cleaner, and more efficient, resulting in a better more polished finish. With the improved, appropriate tooling you won’t have to worry about them glazing over or melting at high temperatures. However, in certain cases, with super hard concrete, some may still prefer the wet process, initially at least, but it’s not necessarily mandatory.
If you are unsure about what to do or how to begin a job, feel free to reach out with any questions or concerns and one of our product specialists would be happy to help.