What RPM to cut granite?

The speed of cutting granite does not have a fixed value, it mainly depends on the diameter of the saw blade. The larger the diameter, the lower the required rotational speed.

 

For professional stone cutting, a more scientific control indicator is linear speed. When cutting granite, the linear speed of diamond saw blades is usually controlled between 25m/s and 35m/s. For granite with high quartz content and particularly hard texture, the lower limit value (around 25m/s) should be taken.

The following is a reference table for the recommended line speed of saw blades with different diameters:

Diameter of Blade	Recommended speed (rpm)	Maximum safe speed (rpm)
110	5200-7300
350	2592	5500
400	2268	3820
500	1814	3055
600	1512	2550
900	1008	1700
1200	756	1275
1800	455
2200	408
2500	327

*Note:

• The rotational speeds in the above table are mainly theoretical values calculated based on "linear velocity=30m/s". In actual use, please be sure to follow the "maximum speed" marked on the saw blade product and never exceed this value
• The above data is for reference only, please pay attention to discernment

 

 

Actual speed cases of different devices
The following are the actual speed parameters of several common granite cutting equipment, which can give you a more intuitive feeling:

• Large bridge cutting machine: This type of professional equipment uses saw blades with larger diameters (such as Φ 350-450mm), and the spindle speed is usually around 6000 rpm.
• Small desktop cutting machine: For example, a regular stone cutting machine with a power of 3-4kw, when using a Φ 350-500mm saw blade, the speed is about 2340 rpm.
• Handheld cutting machine:

The pneumatic tool with a Φ 110mm saw blade can reach a speed of 12000 rpm and is suitable for fine cutting of sheet metal.

There are also handheld models with a speed of 6500 rpm for larger cutting areas.

 

Core Principles and Calculations
If you want to find the most suitable speed for your existing saw blade, you can follow this principle: the speed must match the diameter of the saw blade.

 

You can use this formula to calculate the reference speed:
Reference speed (rpm)=(line speed (m/s) × 60 × 1000)/(saw blade diameter (mm) × π)

 

Substitute the linear velocity of 30m/s into the formula and simplify it as:
Reference speed ≈ 573000/saw blade diameter (mm)

 

For example, a saw blade with a diameter of 180mm has a reference speed of approximately 573000/180 ≈ 3183 rpm.

 

Finally, it should be noted that choosing high-quality diamond saw blades can not only improve the efficiency of cutting granite, but also greatly reduce risks. Choosing Huice diamond granite saw blades can help users improve the efficiency of cutting granite.

When using a handheld angle grinder to cut granite, in addition to selecting the appropriate speed, wet cutting (water cooling) must be used to protect the saw blade and operator's health, and dust masks and goggles must be worn.