When you’re shopping for a concrete floor grinder, there are several features you need to consider – electric or propane grinders, walk behind or ride-on grinders, etc. However, you also need to consider how the discs move to get the job done – they can either be “planetary grinders” or “rotary grinders.” To help you choose which one is right for you, we’re taking an in-depth look and comparison.

How Do Planetary Grinders Work?

A planetary grinder gets its name due to its similarity to how planets work. There is a large main disc that acts as a central point around which several small discs rotate at different speeds from the large disc. The small discs all grind or polish the surface simultaneously while the large disc doesn’t come in contact with the floor. Think of it like the large disc is the sun and the small discs are the planets orbiting the sun while also turning on their own axis.

Benefits of Planetary Grinders

Planetary floor grinders are generally lightweight compared to rotary grinders. Because of this, they are easier to operate and maneuver, but this also means they are ideal for less intensive grinding tasks, like smoothing a garage floor or opening up concrete to add an epoxy coating. Planetary grinders are also good for polishing concrete and stone, but as this requires more skill, a more experienced operator should be tasked with this type of project.

How Do Rotary Grinders Work?

While planetary grinders use belts and pulleys to move the discs, rotary grinders utilize geared construction. In a rotary floor grinder, there may be only one or two large discs that rotate and directly grind the floor. Other styles may have smaller discs that are on one plane or overlapping planes. Unlike a planetary floor grinder, a rotary grinder will either have one or two large discs or several small discs – not both.

Benefits of Rotary Grinders

Rotary grinders are generally significantly heavier than the planetary style which allows them to be used for more intensive tasks. Rotary floor grinders are generally used to remove thick rubber coatings, heavy layers of paint, or quickly polish a floor. Because of the weight, they are harder to operate and generally require more training and skill, but once an operator is comfortable with how they handle, they can complete difficult tasks more quickly.

Choosing a Planetary or Rotary Grinder

If you’re trying to determine which option is right for you, you have to consider the types of jobs you typically do and the skill level of your operators. If you primarily need a grinder for light tasks, like residential use, a planetary grinder, such as the Airtec BS-650-EL may be right for you. On the other hand, if you have an experienced crew or can spend time with training and you will be using a grinder primarily for heavier tasks, a rotary style like the Prep/Master 3030 may be better to get the job done.

Contact Us for Your Concrete Floor Grinder

At Buy Manufacturers Direct, we have a wide selection of floor grinders to choose from, so you’ll be able to choose the one that’s best for your business. To get a quote or learn more about which one is best for you, reach out to our experienced customer service team today at  (815) 324-8071 or by filling out our contact form to get started!