180mm vs 230mm

[greek]

most of 180 mm grinders work 8000 to 8500 rpm 230 ones are at 6000 to 6600 will i get a faster cut or grinding with the faster one ?

 

[shenion]

If you calculate the speed of the edge of the disk, they will be about the same.

The larger disks will last longer as they have more material and run cooler.

 

[KemppiFrog]

Do not be tempted to run big discs on the smaller faster grinder. Potentially very dangerous, as they can disintergrate from the centrifugal forces. Usually the guard stops you doing it, but just pointing it out.

 

[Lawnmowerboy]

Will be about the same cut speed wise as it's the surface speed of the disc that makes the difference.

 

[chevy2]

Do not be tempted to run big discs on the smaller faster grinder. Potentially very dangerous, as they can disintergrate from the centrifugal forces. Usually the guard stops you doing it, but just pointing it out.

Well pointed out,
some people that run both 9" and 4.5" grinders fit the worn down 9" discs to the 4.5" grinders once they're worn down to that size to get more use from them, big no no as they're not speed rated for the faster running 4.5" machines.