Planning stage - epoxy on garage floor

[cwrandolph]

I am putting my plan together to epoxy coat on my garage floor. The floor has an old coating of paint which will need to be removed. I bought a 7” diamabrush for my side grinder and plan to chip away at the old paint as time permits. I want to fill the contraction joints prior to coating the floor. Here’s where I need some advice: The contraction joints in my floor are saw cut and, in some places, one side of the joint is slightly higher than the other. If the joint is filled it seems that the sharp corner of the high side will be visible. I feel like I need to grind down the high side a bit to break that edge and blend it to the other side. What tool should I use to do this? A diamond cup wheel on my side grinder? It doesn’t seem like the diamabrush is the right tool for this – maybe it would even get damaged hitting the edge of the saw cut. Would a diamond cup wheel leave gouges? Any advice is appreciated.

 

[Wileel]

Diamond cup on your angel grinder will be the ticket! That little thing is a monster and will remove TONS of material

 

[NitroShark]

And be sure to get a dust shroud and a proper vacuum. Lots of dust will be created.

This is what I use for that.



.

 

[sweetk30]

i just got my norton 4" diamond cup double row grinder wheel off ebay brand new for about 30 bucks shipped . lowes wanted 70ish + tax at my local store .

15 of them on evilbay now starting at 24 / 30 / 35 each all with free shipping .

and i ground down a 2ft long section in my shop were the slab shifted years ago and it made a TON of dust even with a 42" barn fan blowing behind me on high out the 10ft x 10ft shop door open .

but as said this thing eat that concrete for a snack and didnt even flinch at it . make sure you have breathing and FULL face mask for dust and flying chunks . and hold on to the grinder it will eat fast .

 

[cwrandolph]

Thanks for the advice. I will look into getting a diamond cup grinder. I have the Diamabrush dust shroud so that should work with the cup grinder as well.

 

[massarogi]

I got a DEWALT DWE46153 Surface Grinding Dust Shroud Kit, 5" and it worked perfectly, picked it up on amazon for 199.

 

[Armorpoxy]

Seems like you have the correct tools. A Diamabrush is fine for light grinding, and prep, but not for heavy grinding or 'leveling', for that you need a true diamond cup wheel or similar tooling.

Agree, please everyone wear dust masks when grinding.

 

[sweetk30]

Agree, please everyone wear dust masks when grinding.

friend of mine is in the trades business and in new york i guess the rules have changed and they now have ********* rules with cutting / grinding concrete . he and his other co workers had to go to a class to prep them for the new stuff coming down the line .

if wet work tho its fairly stright forward easy still . the dry / dusty work has gone crazy .

 

[LegacyIndustrial]

This is the new norm.
Hepa vacs attached to any dust creating tools.

 

[bobj49f2]

What are you using to fill the expansion joints? I have an existing floor in the pole building that came with the house I bought three years ago. I am insulating and heating the building. The floor, while in good condition has a gritting texture, now smooth like a finished concrete floor and I want to epoxy coat it but fill the joints first.

 

[cwrandolph]

What are you using to fill the expansion joints? I have an existing floor in the pole building that came with the house I bought three years ago. I am insulating and heating the building. The floor, while in good condition has a gritting texture, now smooth like a finished concrete floor and I want to epoxy coat it but fill the joints first.

First - I learned that the saw cuts are called contraction joints. I've always called them expansion joints. I haven't bought anything to fill them yet but I'm planning to go with "Legacy's Gel Crack Filler". This stuff is somewhat flexible so, hopefully, it won't crack as the floor expands & contracts.