Rotary vs. Planetary Grinders: What’s the Difference?

There are two main types of concrete grinders, there’s rotary and planetary. The difference between the two is how the grinding discs are situated at the base of the grinder. It’s good to know the differences between the two types to be able to choose the correct grinder for the job.

Planetary Grinders

The base of the planetary grinder is set up with one large main disc with three smaller discs mounted to the larger disc. The smaller discs rotate at a different rate of speed than the large disc. The smaller discs are all in the same plane, so they all are in contact with the floor at the same time. The larger disc is not in the same plane so it does not make contact with the floor.

Planetary grinders are typically lighter weight than rotary grinders, this makes them easier to maneuver. They are made to move across the floor in a straight line pretty easily, which puts a lot less stress on the operator. Due to the lightweight build of the planetary grinders they work a lot better on not very aggressive jobs like smoothing down a concrete floor or preparing a floor for an epoxy coating or overlay. Planetary grinders can also be used for polishing concrete, but it is suggested that a more experienced operator use it for this type of work.

Rotary Grinders

There are many different types of rotary grinders, but it is easy to identify that it is a rotary grinder from the disc configuration. The discs include a large that rotates along the base that directly grinds the floor. There might also be several smaller discs along the base that rotate in the opposite direction. They smaller discs can be on the same plane or they may overlap. If the rotary grinder has several smaller discs there will not be a large central disc like you will find with a planetary grinder.

Rotary grinders are quite a bit heavier than planetary grinders. They do not have belts or pulleys like planetary grinders do. Because of the way these grinders are built they are very heavy which allows the grinder to reach faster rotational speeds than planetary grinders can. The weight also causes the grinder to be difficult to maneuver, which requires more training to operate. The weight can also be taken advantage of by experienced users by completing more intensive tasks at a faster rate, such as preparing a concrete surface by removing layers of paint or heavy mastic. Rotary grinders also polish concrete better when used by an experienced operator. (Click here for more information about concrete grinders.) (Click here to surface prep equipment.)

There are so many creative and custom options for finishing concrete, but first and foremost important is the concrete itself. At Custom Concrete Creations we have state of the art equipment and a properly trained team with years of experience. Custom Concrete Creations is a premier contractor serving the Omaha area as well at the Midwest. Give us a call or send us an email for your custom concrete finishing needs today!