To avoid these ads, REGISTER NOW!

Concrete grinding with DG150

xrox

Member
Joined
Jan 30, 2023
Messages
5
Planning on using a rented DG150 with vacuum attachment to grind our small workroom floor (140sqft) to prep for epoxy. They have many different Hilti diamond cup wheels I can rent with it. Any suggestions on which one I would need for this type of job?
 
To avoid these ads, REGISTER NOW!

FJ4FUN

Well-known member
Joined
Jul 28, 2014
Messages
628
Location
NorCal
Planning on using a rented DG150 with vacuum attachment to grind our small workroom floor (140sqft) to prep for epoxy. They have many different Hilti diamond cup wheels I can rent with it. Any suggestions on which one I would need for this type of job?
If removing a coating use the SPX wheel, if just grinding concrete the P-Universal wheel should take care of it. Check with the rental center for their recommendation.
 
OP
X

xrox

Member
Joined
Jan 30, 2023
Messages
5
Thanks, I didn't get the impression the kid at HD had any knowledge on diamond cup wheel applications. I'm actually rethinking this project as I realized there is no vapor barrier under the slab (this is in a basement). Never had any moisture in 17 years through the floor. However, I've heard it is not good to put epoxy on a basement slab without a vapor barrier.
 

FJ4FUN

Well-known member
Joined
Jul 28, 2014
Messages
628
Location
NorCal
Given the season and the fact that you have not personally experienced moisture issues, this would be a great time to do a simple "plastic sheet tape down test" to determine if there is reason to be concerned. If the test fails the 2nd step would be to perform a simple Anhydrous Calcium Chloride test (which are readily available and inexpensive) or, you could skip straight to the Calcium Chloride test. Either way they're easy to do and will let you know what you've got. Depending on the results, Wolverine Coatings does have specialized primers to address increased levels of Moisture Vapor Transmission.

To perform the Plastic Sheet Tape Down Test:



To see if this condition affects your floor apply a 4’ x 4’ sheet of clear plastic (such as heavy-duty polyethylene) to areas of the garage floor. Tape down all the edges with duct tape and leave it alone for 24 hours. If water droplets appear on the inside of the plastic, or if concrete appears wet (darker in color), moisture is trapped in the concrete floor. If the concrete fails moisture test, please contact us regarding further testing and material options before coating.

With regards to the grinder rental, I really encourage my customers to go to a dedicated equipment rental yard like Sunbelt Rentals. They charge the same, the equipment is typically maintained much better, they have a larger selection of options, and you get knowledgeable support.... ;-)
 
Last edited:
To avoid these ads, REGISTER NOW!
OP
X

xrox

Member
Joined
Jan 30, 2023
Messages
5
Thanks, I can do both tests easily, but I was under the impression that the current insitu moisture level is not the only problem. In other words, is moisture a problem only during application and curing of epoxy, or is moisture at any time (like months after curing) going to also be a problem due to the lack of a vapor barrier?
 

FJ4FUN

Well-known member
Joined
Jul 28, 2014
Messages
628
Location
NorCal
Thanks, I can do both tests easily, but I was under the impression that the current insitu moisture level is not the only problem. In other words, is moisture a problem only during application and curing of epoxy, or is moisture at any time (like months after curing) going to also be a problem due to the lack of a vapor barrier?
Good questions and the answer to both is yes. The tests do represent a snapshot in time which is why I mentioned that this is an ideal time (middle of winter) to check. You had mentioned that in 17 years you've never had any issues with moisture so more as a double check, I'd recommend the MVT testing. It's easy and cheap to do and should give you reassurance that all will be fine. If all checks out, and the MVT tests confirm acceptable levels, I would advise that you grind the floor and put down 10-20mils of our BondTite 1101 primer followed by either one of our flake floor systems or our CFLC if a solid color finish is what you're looking for.
 
Last edited:

Steve_P

Well-known member
Joined
Sep 15, 2010
Messages
5,222
I guarantee I don't have a vapor barrier beneath my basement garage slab and it was no issue with epoxy. It dried in a few days and the only issues I had were from hot tires doing very limited damage where the car was parked in the first week or so.
 
To avoid these ads, REGISTER NOW!
Top Bottom