The importance of choosing the right blade for your demo saw

Allcon Demo Saw_IMG

Cutting rebar or reinforcing with a demo saw and abrasive blade is not exactly the safest occupation. Choosing the correct blade is of utmost importance.

Unfortunately, there are many of us who can tell you first hand that the effects of blade failure can be catastrophic to the user and those in the immediate area.

Cut off saws vs demo saws

Metal cut off saws (electric) and demolition saws (petrol) are very different beasts. Aside from the fact that they are powered differently, they also operate at very different speeds and require different blades.

If you were to put a demo saw blade on a cut off saw, you would not notice much difference apart from it cutting slower. However, putting a cut off blade on a demo saw is a recipe for disaster.

Simply put, a cut off saw operates at around 4000RPM, a demo saw operates at 4700RPM. If you work out the sums, the cutting edge of the blade is travelling at over 300km per hour. The force generated by the additional RPM can cause a standard cut off blade to shatter, potentially maiming the operator or anyone in the vicinity.

It’s therefore easy to see that using the wrong blade can be a massive health and safety issue. Get it wrong and you could hurt yourself and others. The financial ramifications of getting it wrong is not something anyone would like to think of, so let's avoid the above and get the right blade for the right machine and job.

How do I know which blade is safe to use for my demo saw?

There are two things to check – the RPM rating and the thickness.

Firstly, the maximum RPM of the blade is normally printed on the outside of the blade. For cut off saws the RPM is usually 4400RPM. For demo saw blades, it’s usually 4800RPM. If the RPM is not printed on the blade, do not risk using it.

Secondly, demo saw blades are generally thicker than cut off blades. Depending on the blade size of the saw, cut off blades are around 2-3mm thick whereas demo saw blades range from 3.8mm to 4.4mm.


So next time when you’re ordering blades for your demo saw, just check what the RPM rating is. If you’re being offered a cheap product, there may be a reason why it’s cheap. It may save you dollars, but this is hardly worth the risk of injury.

Need expert advice on demo saw blades? Talk to the team at Allcon

We’re a family business with over 100 years collective experience in specialist concrete construction products, so we know the hard truths about concrete.

To view our selection of abrasive wheels for grinders and demo saws, simply click here or to get in touch with us, call us on 1300 255 266.

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