What segmented masonry blade for a circular saw?

[isidore12]

I need to cut brick pavers, 50mm thick.

I have two circular saws: one 165mm and one 185mm diameters, both with 20mm bore.

It has been surprisingly difficult to find a (segmented) masonry blade for either of my circular saws.

It is possible to have a smaller blade (6, 6-1/2 or 7 inches), and a bore of 22.2mm (7/8 inches) using a reduction ring.

Would you have anything which would fit?

Thank you

[JacobZ]

Hi @isidore12,

The reason you’re struggling to find a suitable blade is that manufacturers don’t typically produce concrete or masonry blades specifically sized for standard circular saws. Most diamond blades are designed for angle grinders or dedicated concrete saws, which use different bore sizes and higher RPM ratings. This is intentional to prevent people from fitting them to tools not engineered for masonry work.

You should not attach a concrete-cutting blade to a standard circular saw because circular saws are not designed to handle the stress and conditions of cutting concrete. Concrete cutting generates intense heat, dust, and vibration, which can quickly damage a regular saw’s motor, bearings, and guards. Most circular saws also lack dust suppression or cooling systems, so silica dust can clog the vents, overheat the motor, and pose serious health hazards when inhaled.

Instead of looking for a blade to fit your circular saws, I'd suggest using an angle grinder, or hiring a Demolition Saw as they are designed for this work and thus have the accessories for it.

Let me know if you have any further questions.

Jacob

[isidore12]

Thanks for the advises

Yes, I am always concerned with safety, cuts and toxic dust.

I use PPE including face respirator, cut-resistant gloves and safety goggles.

I also attach a Dewalt wet and dry Vacuum to the circular saw with a HEPA Filter.

In those conditions, do you think there is still a safety risk?

I would prefer avoid a Demolition Saw as the blade is much more exposed.  

I found that turbo diamond disk, which actually fits:

https://www.bunnings.com.au/diablo-diamond-disc-7-diamond-turbo-cut-off_p0719414

[isidore12]

Another possibility is to use a Manual Block Splitter.

It can be rented or bought for around $400.

It may not be able to handle small cuts.

[JacobZ]

Hi @isidore12,

I still wouldn't do it. The manufacturers of circular saws would not recommend it, and neither would I. Standard saws are not made to cut concrete.

I missed that you were cutting pavers when I first read your post, which makes me realise that a Brick Saw would be your best option. It is set up for wet cutting and has a slide that runs the paver through the saw itself, which is much easier to manage and with the relevant precautions still in place, much safer.

I think this would be the best option that would combine ease of use and safety.

Let me know what you think.

Jacob

[isidore12]

Yes, it makes much more sense, and it looks much safer to use

I was wondering if there was a place where they would do the cuts for me?

I have about 14 cuts to do at most. Instead of bringing the gear home, I'll bring the 14 bricks to the shop...

[Noyade]

Morning @isidore12 

"I found that turbo diamond disk, which actually fits:

https://www.bunnings.com.au/diablo-diamond-disc-7-diamond-turbo-cut-off_p0719414"

This is just an amateur's experience. But 15 years ago I wanted to cut a 4" X 24" piece from a concrete sheet (15 mm thick).

By chance, a 'supermarket' had on clearance ($50) a wall chaser.

With the supplied spacers you could reduce it to one blade - 125 mm diameter with 1,700 watts (2.5 HP)

I thought it was gonna cut the concrete sheet like a hot knife through butter.

In the end it would been faster to cut with a butter knife.

I can't explain the physics - but the machine was hopelessly inadequate.

Hence my thought is to seriously reconsider that 7" cutter attached to your, what is essentially, a wood saw.

Instead, go with the brick saw mentioned above.

Cheers.

[MitchellMc]

I’m not aware of any businesses that routinely offer cutting bricks for you @isidore12. One option could be to contact a professional paving installer, as they might be willing to cut the bricks for a small fee.

Alternatively, you could hire a handy person who already has the right saw and experience to make the cuts. Services like HiPages or Airtasker are good places to find someone local who could help.

Mitchell