I have a grinder with a Dewalt diamond cup wheel I have been using to remove cosmetic issues on the floor of my basement before staining the floor. I am grinding the whole floor. I am about 1/2 done and need to get the diamond cup off the grinder but I am unable to do so. It is a reverse screw, yes I know I am turning it the right way, I've taken it off twice before.
I have also tried spraying some WD-40 in the threads and tried holding the lock with one hand and striking the wheel with a mini-sledge to loosen the diamond cup. Its still not coming off. I have a dust shroud on the grinder so I can't get a wrench on the back of the diamond cup. I can't take the dust shroud off without 1st taking off the cup. Any ideas how to get this thing off?