Epoxy-coat adventures

[thrasherx]

Long-time lurker here looking for some advice before I dive-in headfirst with a full-kit of Epoxy-coat. My garage is close to 400 ft^2, and is 7 years old. Here's what I've accomplished so far:

Swept
Leaf-blew
Paint thinner on paint stains
Scrubbed with dilluted TSP
Rinsed
Pressure washed to remove paint
Let Dry
More TSP
Simple Green
Dish soap
Rinsed
Pressure Washed

After all of this, I still have remnants of oil spills and paint stains. I picked up some more chemicals yesterday in hopes of avoiding diamond grinding. I have an angle grinder with a DeWalt diamond wheel, but it tends to be agressive and I don't want to make more work for myself. I have a few small to medium oil stains, a few latex paint spills, minor rust spots, a few tire marks (not sure if from oil or something else) and pinoles/imperfections in the concrete.

Oil stains:
I bought more powder and liquid TSP. My first approach of slightly diluting then leaving on the stain for a few hours didn't pull up much oil. Should I go with the liquid TSP?

Latex paint (see picture):
At this point the stains are faded and likely removed from the surface. Will mineral spirits do the trick in wicking up the rest?

Rust:
I've read that muratic acid will eliminate rust spots. Will these impede the epoxy's ability to bond with the concrete? If I do the acid etch that came with the Epoxy-coat kit, do I need to pre-treat this with muratic acid?

Tire Marks (see picture):
Do I need to grind these spots? As stated previously, I'm not sure what material is embedded in the concrete. It could be rubber, or possibly some oily substance.

Concrete Imperfections (see pictures):
Some of these are divits smaller than a dime, and 1/2" deep. Others are spots where the polished surface has been chipped. I have a few concrete filler products, as well as a small bag of Quikrete. I've read that Liquid Nails is acceptable for filling holes, and that the Epoxy bonds. I also know I can just fill with Epoxy, but I'd prefer to fill before I coat the floor, as I'm not sure how much extra I'll have to spare. The worst-case situation seems to be Quikrete followed by the diamond wheel. Thoughts?

Thanks for reading this post. I've been searching the forums, and reading as much as possible. I've put ~10 hours into surface prep thus far, and am determined to create a good profile for the epoxy. If diamond grinding is the only option, I'll just have to bite the bullet. I'm not 100% confident that acid etching will cut through the stains that remain. What's the community's advice on how to procede?

 

[LegacyIndustrial]

You need to grind that floor. Post grinding fill any divots, cracks, etc... with a gel epoxy crack filler.

Bondo will do it in a pinch or a tight budget.

 

[thrasherx]

You need to grind that floor. Post grinding fill any divots, cracks, etc... with a gel epoxy crack filler.

Bondo will do it in a pinch or a tight budget.

Thanks. That's obviously not what I wanted to hear but, in the end, I want to do it correctly.

 

[thrasherx]

On second thought, is there any disadvantage to acid etching, then using the angle grinder with diamond wheel on the spots that didn't get etched? Home Depot is an hour away.

 

[Shea]

You need to grind that floor. Post grinding fill any divots, cracks, etc... with a gel epoxy crack filler.

What he said ^^^^^

I would grind if you can do it. The main reason is because of the tire marks in the concrete. Epoxy will not bond with any silicone that is still in the concrete and acid is not a good product for removing any type of oils. Here's an article about acid etching vs grinding for a garage floor that might shed some light.

 

[thrasherx]

Thanks! On the bright side, I can return all of the extra chemicals that I got.

 

[thrasherx]

After researching my options, this (Clark FM 1700 HD) is the machine that I'm looking to rent. The price is $112 for the day.

Does anyone have experience with this unit? Any idea how long it will take do grind 400 ft^2?

 

[Okolowicz]

I used the Diamabrush. It can be rented from Home Depot with the machine for $100 a day and I would recommend it to anyone. It turns a walk-behind floor cleaner into a grinder. It took me about 5 hours to do a 300 square foot space but I had two coats of paint to remove and a lot of stains. I was going to rent a regular grinder but the reviews of the Diamabrush were to good to ignore and I was very happy with the result.

 

[thrasherx]

I used the Diamabrush. It can be rented from Home Depot with the machine for $100 a day and I would recommend it to anyone. It turns a walk-behind floor cleaner into a grinder. It took me about 5 hours to do a 300 square foot space but I had two coats of paint to remove and a lot of stains. I was going to rent a regular grinder but the reviews of the Diamabrush were to good to ignore and I was very happy with the result.

I just picked up the Diamabrush and noticed it can be used either wet or dry. I have a wet/dry vac. Which is less messy long term?

 

[LegacyIndustrial]

Wet makes a slurry. Dry makes dust. Which would you prefer?

 

[thrasherx]

Here are the results after 2 hours of grinding, and a quick sweep with a push broom. I was able to make two complete passes, one in each direction. After the first pass, I put a weight on top of the floor buffer, hoping it would take more off each time. To my dismay, it didn't seem to make much difference.

There are still some faint remnants of stains. Most of the floor now has some texture, but there are still spots (the darker ones) that are smooth.

I have another few hours tomorrow before I have to return the Diamabrush. Should I give it another pass or two, or plan on cleaning, then etching it?

Please excuse the watermarks; I exported these in a hurry. Thanks, everyone!

 

[LegacyIndustrial]

It appears to be done correctly.
If you splash some water on those dark spots, does it soak in or stand on top?

If sits on top you may have to hand-grind a bit.

 

[thrasherx]

That's great news. I'll check the spots for water after work. Thanks, Legacy.

 

[thrasherx]

The oil stains and tire marks still repel water. I used the hand grinder to knock then down more, but they refuse to absorb. Ideas?

I'm still tempted to acid etch. Are there downsides to etching after grinding?

 

[thrasherx]

After the dust settled (no pun intended), things look less promising. I'm pretty sure the Diamabrush that was rented to me was very dull. What do I do?

 

[Shea]

You have a few different options. After reading your OP again, you may want to try an aggressive degreaser to scrub and let soak into those spots for 15 to 20 minutes. While they are still wet, grind in some kitty litter with the heal of your shoe and let it sit for 24 hours to draw the oils out. You could try Pour-n-Restore as well. Many people have had good luck with that.

Another option would be grind deeper with your hand grinder and then patch over the spots with a polymer modified patch kit.

The third option would be the use of an oil stop primer.

Judging by the look of your "before" pics, it just may be a cleaning issue. I've seen much worse that cleaned up fairly well before grinding and didn't have any issues. The one problem that can be a headache is the silicone oils from tires. They tend to soak in more and are very difficult to remove. Sometimes it requires the deep grinding method followed by the patch work.

Good luck

 

[srode]

I had some spots with oil stains that I could not eliminate completely on my floor. Tried scrubbing with acetone multiple times, hit it with a propane torch (some did rise to the surface that I could remove with acetone afterwards doing this), and a liquid concrete oil spot remover sold at Lowes along with multiple applications of 50% muratic acid to get a more coarse surface for bonding. I was never able to get the oil stains completely removed and it these had some water repelancy still when I applied the Epoxy Coat. When I got to the sections with those spots, I started with the spots working the material into the concrete as best I could with a stiff brush. Then applied my epoxy pouring the entire section and squeegy / rolling per the directions. There was some fish-eye on a couple parts and those I just rerolled a few times until it went away. 2 years later no problems with any spots that had the oil stains and the worst one is right under one of the vehicles normal tire stopping point. I did let the floor cure for a week before parking anything on it. Net, I think sometimes you just aren't going to be able to achieve perfect prep work but it may not cause problems for you down the road. Oil does soak into concrete and sometimes you just can't get it all out. Do the best you can and where spots remain make sure you have a rougher surface to help with adhesion. I am not a pro at this but I can say this approach worked well for me.

 

[thrasherx]

Thanks all for the advice and encouragement! When I do put down my epoxy, I plan on backrolling as many times as feasible. I got 2 18" rollers, but I'm not sure I'll need them.

I got some Valspar oil removal product, similar to pour-n-restore, and applied it last night. It's thick like a milkshake and dries into a powder. The directions suggest that, if the first application is insufficient, you try scrubbing in the gel with a stiff nylon brush. I went ahead and did it for my first application. I left it overnight and through the next day. When I came back and checked on it, there were still some wet spots, presumably where the stains were the worst. I swept up and rinsed with a pressure washer, as the product instructs.

As I was rinsing, I could tell that the water was not penetrating any better. I have another bottle, but am hesitant to use it based on my first results.

I've hit the spots with the diamond wheel on the angle grinder enough that the pebbles below the skim coat are visible (forgive my lack of concrete terminology).

I only have an hour per day, a few days a week, to work on it. I don't want to rush it, but I'm also losing steam. At this point, I'm considering some kind of primer coat. I'm not sure which ones are good, or if it matters since it won't be my topcoat. That way, if there are fisheyes, they can be taken care of before the final coat. Also, while I'm at it, I'm considering a clearcoat. I've invested too much time and energy into this project for the results to be subpar.

Any suggestions on a good primer and clearcoat?

 

[thrasherx]

Apparently HD gave me the wrong finishing wheel the first time. To make up for it they allowed me to rent the correct one for free.

After a single pass:


After the second pass (perpendicular to the first):


The amount of dust that was generated by the machine:


Finally, the texture does not seem to e that of sandpaper. I won't know for sure until I wash away the dust, but it feels smooth. Should I attempt a weak acid etch, or leave it be? See the last pic for an idea of the texture.

 

[LegacyIndustrial]

Absorb water readily?

 

[thrasherx]

Most areas absorb water ok. The stains still repel. I'm temped to do a coat of primer to work out the imperfections with a cheaper material.

 

[LegacyIndustrial]

Did you try a very light grind in those areas?
An abrasive disk would work good, then prime .

 

[thrasherx]

I've grinded the areas fairly thoroughly with a handheld diamond wheel. What primer would be good? I'm ready to be done with this project.

 

[thrasherx]

Here's where I'm at to date:

-Majority of stains removed, still a few more to go.
-Debating whether to grind, prime, or go straight for the base coat.

Here's a quick and dirty water absorption video. YouTube color corrected it, so don't blame me

 

[thrasherx]

No pressure, but I have to decide by tomorrow if I'm going to rent an EDCO diamond grinder. Obviously, I'd like to avoid it if possible. Thanks!

 

[LegacyIndustrial]

No pressure, but I have to decide by tomorrow if I'm going to rent an EDCO diamond grinder. Obviously, I'd like to avoid it if possible. Thanks!

Tough to see, very blurry.
Looks like the water is being absorbed though.

I would be using a primer.

 

[thrasherx]

Thanks, Legacy. Does anyone have primer recommendations? We have a Benjamin Moore store here, but no guarantee it's local. The big box stores probably have something. I've read people use ~35% solids epoxy for primer, or thinning out some of their base coat. Since my garage is close to 400 sqft, and Epoxy-coat rates their full kits as 500 sqft of coverage, it's an option, but not a great one.

 

[LegacyIndustrial]

Not sure if BM has anything. They don't make epoxy per say.
We have some equitable options if you can wait.

http://legacyindustrial.net/cart/standard-epoxy-coatingprimer-p-103.html

 

[Okolowicz]

Benjamin Moore Has several options that will work. The Super Spec P35 has been used successfully as a primer with epoxy-coat by others on these forums. Also, Sherwin Williams Aquapon 35 has also been used successfully as a primer.

Bear in mind that not all BM stores carry the Super Spec line so YMMV

 

[thrasherx]

At this point I can stand to wait another week. I'll be price-checking and calling around tomorrow. Thanks, all.

 

[thrasherx]

I bit the bullet and applied epoxy this weekend.
The oil stains refused to lift completely, even after a final vigorous scrubbing of dish soap and hot water. Luckily, Legacy Industry's primer went on without a hitch. No problems with the application other than debris
Next I applied the base coat of gray Epoxy-Coat and flaked to desired pattern. Finally, the clear coat was back rolled and non-skid was added. I special ordered non-skid from Epoxy-Coat that is finer then what comes in the kit. Instead of broadcasting over the entire garage, I decided to skip the two spots where cars would be parked (I'd read the annoyance of bare skin and sharp anti-skid).
In the end, it turned out great. Not perfect, but I have to remind myself that it's just a garage.

The recessed lights were also installed last weeks. Whew.





Now all I need is to paint and fix/reinstall the stairs.

 

[19psi]

Looks good! I think I'll start painting mine this week.

 

[Ed Litsch]

That looks great!! You did a great job.

 

[burleyfarm]

Nice job.

 

[thrasherx]

Thanks for the compliments! My wife and I are so glad to cross it off our to do list. We're coming up on a year of home ownership and are wondering if the list will ever end.

Any recommendations on sealing the cracks around the perimeter? I'm not sure if there's a specific silicon that bonds with epoxy.

 

[LegacyIndustrial]

Thrash: great job. Glad our product performed well for you.

 

[rugerlady]

Floor looks really good, wish I would have been on here sooner to help!

 

[thrasherx]

Another GJ member and I helped each other. So glad to have it done. I walk out to my garage several times a day just to admire it. Great products!

 

[thrasherx]

My kids managed to put a few hairline scratches in the clear coat. Should I bother trying to fill them? Would I need to hit it with 80 grit sandpaper and re-roll or could I attempt to fill in with something like q-tips?