We have a 8" pedestal grinder at school, I refused to use it because one of the wheels is so out of balance the machine visibly shakes. As its an academy I cant change it (despite having a certificate) Instead the service providers sub contractor has to do it, they come back every year & say its Ok, I tell them its dangerous, I have told the top brass why i wont use it. This has been going on for 4 years! But i aint using it & nor is anyone else. Such is progress!