It could be said the choice of concrete grinding machines is nothing more than a choice of colour and you won’t be too far wrong but in this post I’m going to shed some light on other factors. So lets take a look at what factors we need to consider when looking at the option of purchasing a grinding machine.
Grinding is all about friction. The more friction we create, the more concrete we can remove. What creates friction in a grinder? Weight!
These come in the form of single or 3-head planetary. Typically these are light weight as the motor size is always small due to the single phase current draw. These concrete grinders are used for small areas, such as bathrooms or for general stock removal. For serious polished concrete these type are no good. They will how ever do small areas quite well.
3-phase is where all the fun begins. The extra power lets concrete grinding machines become heavy. A typical machine weight is 350kg to 550kg. With the ability of adjustable weights you can create different downward pressures for the many different situations that grinding concrete brings. Of course with 3 phase brings portable power generators and large power boxes with big leads. If your serious about grinding concrete, this is what you have to do.
Lets cover single heads first. These grinding machines are typically cheap and simple. Their use is for massive stock removal and pin pointing grinding. The operator has to have skill and long hours of operation is hard work. We typically use ours for floor preparation, levelling and the likes.
The next type of concrete grinder is a 3 head planetary. With variation of head direction vs main planetary these are simple machines designed for great polishing. Not generally good for stock removal vs the 4 head as the 3 head design walk over the floor more than resist any dips or hollows. This is what creates a great polishing machine. Also by nature a 3 head concrete grinder is lighter.
4 head concrete grinding machines are heavier and start usually from the 650 range and up. 650 bring the width of the machine. These start around the 440kg and move up in scale. They grind concrete in a serious way. Large downward head pressure creates loads of friction. Friction = great concrete grinding.
When considering what grinding machine might be for you then the above are the main points with the difference in make giving you the other deciding factors.
Balance – How the machine moves and is balanced. How easy it can be moved around from one job site to another. An awkward grinder is no fun to move around. Make sure you move the machine around before purchasing.
Weights – Whats the weighting system like, is it easy to use ? Are they pull on and off weights or are they moveable weights?
Construction – How well are the concrete grinding machines made ? Factors to consider – Bearing, belts, dust shroud, ability to mist water, handle construction. A fine well machine will work time and time again without breaking. Nothing is worse than doing 100 hours on a concrete grinding machine for it to full apart while your in the middle of a time sensitive job. I know, i have been here before with parts breaking that lead to no work being done. All concrete grinding machines require maintenance but in this case, less is more.