I have always just used the worn down 230mm disks on my 115mm angle grinder without the guard.

But as I am getting older I hope to be getting wiser and have decided I would like to work more safely and set example for the younger ones.

I have lots of these and it breaks my heart to though them away.

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Is there any easy way to quickly get them to the right size so you can use the with the guard in place?