Epoxy - The Next Step

[Reflex]

After posting here a few weeks ago, I received some excellent advice on how to proceed with my floor. To recap, I have a new 2200 square foot shop/slab with a smooth/burnished finish. I've decided to go the extra mile and epoxy the floor. I was fortunate enough to find several people here who know what they're doing and pointed me the right direction. Here's where I am.

I have purchased primer, epoxy, and urethane from Legacy Industrial and have ground the floor. Grinding the floor is where I'm running into some questions/issues.

I tried the 25 grit Dimabrush (dry) and after getting less than 10 square feet done in an hour, I decided to go another direction. I ended up using a Lavina 21" machine with 30 grit diamonds (single button) and did the grind wet. Clean up has not been nearly as tough as I thought it would be and there was 0 dust.

Upon completing clean-up I have discovered two things:

1) I have multiple low spots that are in a line roughly every foot and a half or so. This appears to be due to the way the crew moved the screed board. The low spots/lines are anywhere from 1/32 to 1/16 deep. The Lavina machine would not get down into these areas so they still appear dark with only a few scratches on the surface.

2) I'm not sure I've opened up the slab enough. After 18 hours of grinding, there are areas where I'm quite sure the grinding was done properly, however there are several (like the low spots) where I'm not sure I've got it done properly.

My general thoughts/solution is I'm thinking that maybe I should go back with the Dimabrush (this time wet) and see if it will get into the low spots. If it takes a significant amount of time, so be it.

My questions are:

A) Do you think using the Dimabrush (wet) will get down into the low spots?

B) I'm making the assumption that the Dimabrush will cut better wet; is that true?

B) When complete, the floor will still have low spots, they'll just be properly prepped. Will I see "waves" in my floor?

C) What's the best way to tell if the floor is properly ground/prepped?

Pictures are below.

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Thoughts?

Thanks,

Reflex

 

[Shea]

Due to the flexible blades of the Diamabrush it will be able to access the lower spots without a problem. Before you do that however, test some of those questionable areas with the water drop test. If the area where the water hits turns darker and gets absorbed right away then you are good to go as it. If it just sits there and doesn't absorb or takes more than a minute to do so, then go ahead and run the Diamabrush over it.

The Diamabrush will cut a little better wet, but usually it's not that big a difference. For your floor it might be the difference you need.

In terms of the wavy floor; If you are using color flakes you will see it less. The more flakes, the less you will notice.

 

[Reflex]

Shea,

Many thanks for your input. Did the water drop test, dark spots absorb water, but not quite as quickly as I think they should. Going to hit it with the Diamabrush (wet) to make sure I get the proper prep done.

Again, thanks.

Reflex

 

[mnavillus]

Due to the flexible blades of the Diamabrush it will be able to access the lower spots without a problem. Before you do that however, test some of those questionable areas with the water drop test. If the area where the water hits turns darker and gets absorbed right away then you are good to go as it. If it just sits there and doesn't absorb or takes more than a minute to do so, then go ahead and run the Diamabrush over it.

The Diamabrush will cut a little better wet, but usually it's not that big a difference. For your floor it might be the difference you need.

In terms of the wavy floor; If you are using color flakes you will see it less. The more flakes, the less you will notice.

Shea--is right on track...its hard to tell how bad the existing waves in the concrete without having eyes on it, however from the pics it does not look substantial. 100% full broad cast, blended flakes will assist to minimize the appearance.

Pro tip--Additionally, you could apply the epoxy primer "slightly" thicker in an low area to help flow out a minor discrepancy.

Diamond grinding the floor was the right step! Regardless of which tool you utilized you got to the finish line!

I think your done with that process from what I see in the pics. If there are suspect areas... than try the water test mentioned by Shea above...FYI: You can hand scratch a small area if its needs more prep..


good luck!