I got the Porter Cable grinder from Lowes & the diamond cup wheel from HF. They even gave me discounts I didn't know about & applied coupons to stuff that I didn't know had coupons. The clerks were very friendly & helpful this time.
I forgot to take a picture of my friend when he was all geared up, but he had safety glasses (I made sure to get him some with red on them- red is his favorite color), red & black impact gloves, face shield, dust mask, & gel knee pads. He really liked the knee pads & said he can use them at work (he fixes arcade machines so he has to kneel down a lot). He got to keep all the gear but the face shield (which he said should stay here with the grinder). I used the little 3-gallon shop vac - geared with a dust mask and aviator's goggles. I caught some chunks of debris that flew off & got as much dust as I could. It wasn't quite as bad as I thought it would be. Went back and swept & vacuumed after the dust had time to settle more. Only problem with the shop vac is that it blows air and makes the dust fly more. I have the sheet vinyl lying flat again for now. I was worried it would get marks from being bent & stepped on while rolled over, but it just went back into place. I will need to adjust it more once the floor is smoothed with some leveling patch. I'm thinking of going with Henry 347 just to do a light coat to make it smooth. I know the grinding job wasn't perfect & there was a spot near the corner that got missed, but I wanted to focus mostly on where the toilet will sit.
Here is the before with the botched job (I wish I had removed the cardboard before starting-- but that stuff really got stuck in there-- grinder got it all out though):
After grinding:
It's not perfect, but at least it's not as bumpy. With the patch it should be a bit smoother for the toilet & I might try to fix that one back corner a bit. Didn't want to get too close to the wall with that grinder. I'm not too worried about that corner- I'm going to stick the toilet brush & plunger back there so it won't be a big deal.
The current floor still kind of resembles the surface of the moon, but it's not nearly as bumpy as it was before. The stuff I want to use claims it will dry in 2 hours but I've heard people saying it can take 6 to 8 hours, so I'll be patient & keep cats locked out.