Unbalanced Diamond cup wheel

[Paddy]

I have bought two diamond 4 in dia cup wheels in the last two years. Both have been so out of balance they were not safe to operate. The first one vibrated the screws out of my angle grinder, not to mention my hand felt numb. I took it back

The second one was today. I was mounting on a 5/8-11 to 1/2 in arbor to run it in my radial arm saw. I turned on the saw and watched it reach full RPM. The darn thing wobbled about an 1/8 in and up and down about 1/16. The RAS runs at 3450 rpm vs. 15,000 max for the cup wheel.

Anyone know what's going on?

 

[CalG]

price and country of origin might give first clues.

Stop by a local welding supply and see what is offered there.

"Diamond" cup wheel? Seems like a waste of good abrasive.

 

[Paddy]

Diamond cup wheels are for concrete and other masonry. They work real well at bulk removal. I will try a name brand but any more they are all made in Asia.

 

[radios1]

buy from here. MSC Industrial Supply | Metalworking and MRO Supplies you will NEVER get a defective item from them, they do thorough inspections of the quality of the tools they buy..