Whether you need to cut a concrete slab or a wall, it’s prudent that you have the know-how of cutting concrete with a circular saw. You start off by marking off the cutting path after which you slowly guide the circular saw into the concrete block until it reaches maximum speed. After around every 45 seconds, you rinse and repeat.
Cutting concrete blocks can be a daunting task, especially if you prefer taking care of your place on your own rather than hiring a contractor. Luckily for you, we have this guide below, walking you through every step of cutting concrete blocks with a circular saw.
However, before we get into the details of the exercise in the discussion, we must take into account the assorted questions that need to be addressed for a successful cutting of concrete blocks with a circular saw, such as the type of circular saw and the blade to be used along with it.
Type of Circular Saw to be Used for Concrete Cutting
The type of circular saw that you use for cutting concrete blocks doesn’t really have a significant effect on the process. However, whichever one you go for, make sure that its RPM is above 3000 for a high cutting speed.
What Sort of Circular Saw Blade Should You Choose for Concrete Cutting?
The blade is the most integral component of a circular saw since it is the component that actually comes into contact with the concrete shape to be cut. With the wrong blade equipped to your concrete saw, it is as good as useless.
There are several blades, made up of a variety of materials, available in the market. Here are the three most useful for the purpose of concrete cutting.
- Masonry Abrasive Blade
- Diamond Blade
- Wet/Dry Cutting Blade
Masonry Abrasive Blade
Of the three types of blades mentioned above, a masonry abrasive blade is your choice if you’re looking to get your hands on the most cost-effective circular saw blade. However, its mediocre rate of revolutions in cutting concrete coupled with the fact that it deteriorates far too frequently makes it ineffective if you’ve got plenty of concrete cutting jobs at hand.
Resort to it only when you need to carry out a quick concrete cutting job.
Diamond Blades are not made entirely of diamond. Rather, only their teeth are made up of the composition of diamond and another reinforcing metal. Being the strongest material on earth, a diamond makes for extremely efficient blades that do not wear easily though are relatively far more expensive than the other two options.
A diamond blade for a circular saw is definitely your best bet if you have a lot of concrete cutting jobs to take care of, whether you’re a homeowner or a contractor.
Wet/Dry Cutting Blade
Diamond blades become extremely hot when cutting concrete. To remedy that, wet and dry cutting blades come into play. These blades have the same structural components as diamond blades with slight modifications.
Talking about the wet cutting blade, it is a blade possessing no teeth and while using it to make a cut, a low stream of water must be added. As a result, the blade will be lubricated during cutting and silica dust won’t be released.
As for the dry cutting blade, with its segmented teeth, its design allows it to dissipate heat. Though the long span of this type of blade makes it a reliable option for concrete cutting, it releases silica dust in high amounts during the cutting process. Therefore, it must be used with a dust mask on.
How to Cut Concrete Blocks with Circular Saw
Now that you have gotten a bit of an idea about the type of circular saw and its blade, let’s head into the main highlight of this guide which is the process of cutting the concrete blocks.
- Chalk for marking the desired cut
- A good-quality circular saw
- The right blade, that is not dull to avoid kickback
- Protective gear (respiratory mask, safety goggles, etc.)
- The concrete block(s) to be cut
Step 1 – Put on the Safety Gear
As mentioned before, you are expected to encounter dust as well as noise. The dust is detrimental to your respiratory system and eyes. So, the use of a dust mask and goggles is mandatory here. Similarly, as a countermeasure for the loud noise generated by the entire cutting process, make sure to wear ear protection beforehand. Also – be sure to check out our guide on how to prevent circular saw kickback!
Step 2 – Mark the Spot Where the Desired Cut Needs to Be Made
Before you practically engage with the concrete blocks, you should plan out the cutting process and you do that by marking the concrete blocks with a chalk line. This chalk line will help you guide your circular saw through the desired path.
Step 3 – Adjust the Circular Saw
Set your circular saw at the appropriate ripping size (according to the thickness of the block) and align it with the marks you made. Once that’s been done, launch the circular saw and allow it to reach its maximum RPM.
Step 4 – Begin Cutting
Gently commence the cutting exercise by leading the circular saw into the concrete block. Avoid exerting extra pressure on the tool, keeping in mind that it is the blade, in actuality, that is cutting the block and not the effort you’re making.
Step 5 – Get Yourself an Extra Pair of Hands for increasing Water
This step is applicable in case you’re in possession of a wet cutting blade. The concrete cutting exercise is bound to release significant heat as well as dust. To cater to the mounting temperature of the blade and eradicate dust, water is used.
Step 6 – Stop the Blade After Every Short Interval
While conducting the concrete cutting exercise, it’s imperative to halt the circular saw nearly every 45 seconds. Not only can the continuous cutting overwork the blades, but also, it can generate high amounts of heat, resulting in unwanted outcomes.
General Safety Tips
If you are an amateur working with a circular saw, you are essentially putting your safety at risk. Therefore, it is imperative that you take into account the following tips while handling saws:
- Dress appropriately, as stated before.
- If the blade is taking a while to make a cut, sharpen it.
- Keep the workspace free of other materials as they can cause retractile forces which can make your job more tiring.
- Avoid touching the revolving saw blade and remain patient to the point when it is motionless.
- After the task is finished, turn off the blade and clean it.
- Never use a saw when drunk as a diluted judgment can prove to be harmful to you and your loved ones.
- If you’re in doubt about a particular saw activity, seek professional consultation to be absolutely sure.
- If you need to cut a reinforced concrete, the best approach is to hire a contractor because you will encounter rebar, cutting which may cause cracks to develop in other parts of the reinforced concrete as well.
- For a block of thickness more than 15 cm, try cutting the block from both sides and then, use the sledgehammer to split the block.
Simply put, there are several considerations that must be made for cutting the concrete blocks with a circular saw.
For starters, you must choose a circular saw with a good enough RPM. Then comes the most important part of choosing a blade, for which you have three options: masonry abrasive blade, diamond blade, and wet/dry cutting blade.
If you have a flexible budget and you’re looking for high productivity, diamond blades or wet/dry cutting blades are your go-to options whereas if your budget is a bit tight but you still need to carry out quick concrete cutting activities, a masonry abrasive blade will work just fine for you. In any case, you just need to follow the steps detailed in this guide to make the desired cuts.
An important thing to keep in mind is that if you’re inexperienced in working with saws, you need to accept that some concrete cutting tasks are beyond your level of expertise and for those tasks, you should acquire the assistance of a professional.