Another Epoxy-Coat Project

[snorvet]

After seeing all the amazing epoxy floors on this board, and voiddweller's recent thread, and recommendations from other guys, I decided to go with Epoxy-Coat. I ordered 2 kits yesterday.

Here's a before pic

My floor is 5 years old with no sealer, but contains fiber mesh mixed with the concrete

Here's the process (after I finish wall painting)

1. Clean floor
2. Sand / scarify / grind floor & rinse
3. Acid Etch & rinse
4. Apply first coat epoxy
5. apply second coat epoxy and chips

My first question is this: I called the local rental place. They have gas powered concrete scarifiers, and electric drum and orbital sanders that will rough up the concrete.

They say that the scarifier is normally used to remove pavement striping, etc, and will grind 3/8" if you go slow enough when using it. He said it would probably work if I went fast enough. I certainly dont want to take 3/8" off. This wont get into edges and corners very well.

The drum sander comes with a selection of sanding pads that get as rough as 20 grit. Gets into corners and edges ok.

I know it may be tough to tell without seeing these things, but which tool do you think would be best?

 

[bmwpower]

I would not use a scarifier. I've seen their results and they seem to be very agressive. I would use an orbital sander for sure. It should help maintain a "smoother" final finish, but will still rough up the surface like you want. It will also do a better job of removing the fibers from the surface, too. Unless you're trying to level out a very unlevel floor, don't use a scarifier.

 

[zman]

Ditto on not using the scarifier.. You'll end up with a very rough uneven surface... I'm trying to figure out why you feel the need to sand or scar the floor, it looks in good shape and should only need a really good cleaning...

 

[krooser]

I used the orbital to get the little fibers off the surface.....If it takes you over 1/2 hour, you're screwing off!

 

[snorvet]

thanks guys - it's unanimous - no scarifier. I'll rent the sander. I was worried about the scarifier because it seems it would be agressive and expose a lot of fiber. The floor seems very smooth now. thats the only reason I want to rough it up a little. everyone says preparation is the key so i figured I'd sand and acid etch.

Krooser - this garage is so small (22x24) - it shouldnt take a half hour.

 

[REFLEXX]

I was told (and am renting) the square floor sanders that take a 12x18" (or so) sheet. My local Home Despots rent them. 60-80 grit for a nice finish.

The round orbitals will not get into corners (if that matters to you)

I hope to be doing this in about 3-4 days!!!

PS- I painted the floor in my storage room (12x14ft) with Behr Concrete Paint. I'm glad that I'm not going to do the rest of the shop that way. It's a dull, ugly finish that shows every bump and void. But it was only $40 in materials.

 

[snorvet]

Reflexx - You're right on the sander. My rental place is suggesting a drum sander that sands a rectangle . That seems like it would be better in the corners. I hope to be doing mine next weekend.

 

[voiddweller]

I totally agree that the scarifier would be a big mistake. From what I can see, your garage does look to be about ready for the application.

Did you do the 'drop of water test?' If not, place a drop of water on the prepped floor and see how long it takes to absorb into the surface. If the water just sits there, you will need additional prep on the surface. If it soaks in, you are all set.

After diamond grinding, I used a 'pole/drywall sander' in the corners and was satisfied with the result.

Good luck with your project!

 

[snorvet]

I totally agree that the scarifier would be a big mistake. From what I can see, your garage does look to be about ready for the application.

Did you do the 'drop of water test?' If not, place a drop of water on the prepped floor and see how long it takes to absorb into the surface. If the water just sits there, you will need additional prep on the surface. If it soaks in, you are all set.

After diamond grinding, I used a 'pole/drywall sander' in the corners and was satisfied with the result.

Good luck with your project!

Thanks, keep us posted if you have any new developments with your floor - even though you're done

I'll have to try the drop of water test after i clean the floor, but yesterday I had the door open while it rained and the water kinda sat there and made a muck with the drywall dust.

 

[voiddweller]

Thanks, keep us posted if you have any new developments with your floor - even though you're done

I'll have to try the drop of water test after i clean the floor, but yesterday I had the door open while it rained and the water kinda sat there and made a muck with the drywall dust.

I know exactly what you mean. When I spoke with the tech at Epoxy-Coat, he told me that would happen if I attempted to wash it.

When I finished sanding and grinding, I swept out the garage 2 or 3 times, mopped it, and swept it out again after it dried.

I took my finger and wiped it on the surface. It was pretty much clean at that point...

 

[snorvet]

I know exactly what you mean. When I spoke with the tech at Epoxy-Coat, he told me that would happen if I attempted to wash it.

When I finished sanding and grinding, I swept out the garage 2 or 3 times, mopped it, and swept it out again after it dried.

I took my finger and wiped it on the surface. It was pretty much clean at that point...

I think I'm going to pass on washing the floor - I'm going straight to grinding/ sanding. Should be doing the grinding/sanding this weekend. I got my Epoxy-Coat delivered today. I may wait til mid-May to put down the epoxy. I heard its best if done at a warm temp.

 

[REFLEXX]

Snor,

I just got off the phone with the lady at Epoxy-coat. I wanted to confirm with her before I got started myself. She said "sanding with 80-100 grit is just as good as etching. You just save yourself 6 hours having to wait for the floor to dry" "make sure the floor is dust free, no mopping" "vac/broom then apply"

I also asked about expansion cracks. She said to "NOT fill them in with caulk or anything. The epoxy will split if expansion occures and might start to peel up"

That's what I'm doing today too!

 

[bajones9181]

Snor,

I just got off the phone with the lady at Epoxy-coat. I wanted to confirm with her before I got started myself. She said "sanding with 80-100 grit is just as good as etching. You just save yourself 6 hours having to wait for the floor to dry" "make sure the floor is dust free, no mopping" "vac/broom then apply"

I also asked about expansion cracks. She said to "NOT fill them in with caulk or anything. The epoxy will split if expansion occures and might start to peel up"

That's what I'm doing today too!

I'm about to do epoxy-coat on my floor as well. My floor has no expansion joints but there are a few cracks in the concrete from the ground heaving. Are these cracks ok to fill in caulk or epoxy?

 

[snorvet]

Snor,

I just got off the phone with the lady at Epoxy-coat. I wanted to confirm with her before I got started myself. She said "sanding with 80-100 grit is just as good as etching. You just save yourself 6 hours having to wait for the floor to dry" "make sure the floor is dust free, no mopping" "vac/broom then apply"

I also asked about expansion cracks. She said to "NOT fill them in with caulk or anything. The epoxy will split if expansion occures and might start to peel up"

That's what I'm doing today too!

Reflexx,

Thanks - I'm on my way to look at the sanders at the rental place. I have no expansion joints or any cracks.

Bajones - good question on the cracks - I dont have an answer, but I hope we get one because I'm going to do my attached garage later, and it has cracks and saw-cut expansion joints

 

[snorvet]

Havent sanded the floor yet, but sanded corners and edges with my palm sander. It's doing a great job getting paint and drywall compound off the floor. But I've got a spot where I think I spilled gas or gas/oil mixture several years ago. Grinding and sanding isnt changing the color of the spot, but it feels the same as other sanded areas, maybe a little smoother.

After I rent the drum sander, I plan on etching the whole floor. Should I do something else with this spot first? I don't know if a cleaner will take off the spot if grinding and sanding won't.

Here's the spot.

 

[bmwpower]

Havent sanded the floor yet, but sanded corners and edges with my palm sander. It's doing a great job getting paint and drywall compound off the floor. But I've got a spot where I think I spilled gas or gas/oil mixture several years ago. Grinding and sanding isnt changing the color of the spot, but it feels the same as other sanded areas, maybe a little smoother....

If you've spilled something there before, you should degrease it first. Does water bead up on the spot?

 

[snorvet]

I had water on my shoes that didn't evaporate from the spot as fast as on the clean part of the floor. So I scrubbed it several times with simple green. This morning it looks about the same as yesterday. I'm going to try it again.

 

[bmwpower]

I had water on my shoes that didn't evaporate from the spot as fast as on the clean part of the floor. So I scrubbed it several times with simple green. This morning it looks about the same as yesterday. I'm going to try it again.

I would recommend trying something a little stronger than simple green, maybe a solvent, followed up by a stronger degreaser/detergent like the Behr stuff from Home Depot.

I used acetone on some spots of my floor, followed up by the Behr degreaser stuff.

 

[snorvet]

Thanks, I'll pick up some extra strength stuff today

 

[snorvet]

rented a shotblaster yesterday. It roughed up (and cleaned up) the surface real well. I may have to do more hand grinding along the edges.

 

[bajones9181]

Floor looks good! Where did you end up getting the shotblaster from? How much did it run if you don't my asking?

 

[snorvet]

Floor looks good! Where did you end up getting the shotblaster from? How much did it run if you don't my asking?

i got the shotblaster from sunbelt rentals in joliet. it was expensive but they were the only place i could find one. $389 for one day + $72 for 2 bags of shot.

 

[snorvet]

Yesterday I acid etched per the Epoxy-Coat instructions that call for diluting 1 quart of acid into 4 quarts water. It didnt etch very well, since I think it was too diluted.

 

[BubBud2]

Snorvet,
did you ever get the darkened spot off the floor? I've cleaned some old spots in my garage with brake clean before. I know that NAPA stores have concrete cleaners available also.

 

[snorvet]

BubBud2-

First I took the shotblaster to the spot and it ground it down and lightened it a little, but then I poured concentrated acid on it and scrubbed it and I cant tell where the spot was now.

Thanks for the brake cleaner / NAPA store idea - I have a bunch of spots in my attached garage i'm going to deal with

 

[JBL]

Make sure you check for hydraulic moisture issues before painting. If there is not a vapor barrier under the concrete the paint will lift regardless of how well you prep it.

 

[snorvet]

Make sure you check for hydraulic moisture issues before painting. If there is not a vapor barrier under the concrete the paint will lift regardless of how well you prep it.

I dont think that hydraulic moisture will be a problem. I cant remember if the concrete guys put down a moisture barrier, but I live in a very dry sandy area. I dont even have a sump pump for my basement

 

[voiddweller]

Hi Snorvet,

How is the project going? Any updated pics?

 

[snorvet]

I acid etched and rinsed a week ago, and it took a week to dry. I grinded the edges last night, because it didnt look like the acid etch did anything.

today's epoxy day. I'll have pics tonight or tomorrow morning.

 

[04 Navi]

That's interesting that you waited for it to dry. When I used the Griot's garage paint they wanted to floor damp right after the etching. Mine stayed down awesome for four years and then we moved.

 

[snorvet]

That's interesting that you waited for it to dry. When I used the Griot's garage paint they wanted to floor damp right after the etching. Mine stayed down awesome for four years and then we moved.

I've seen other epoxy instructions that say to apply it damp also. But the epoxy-coat instructions said make sure its dry so I ran fans and the heater for 5 days

 

[snorvet]

The first coat is down. Here is a pic of the Epoxy-Coat Kit

I mixed two parts A to one part B about 3 quarts at time in the big bucket. First I cut in the edges with the brush. Then poured a little bit on the floor in sections, squeegied it around, and then rolled it. Did everything per Epoxy-Coat instructions. The plastic epoxy stirrer in the kit broke while mixing, so I had to use a metal paint mixer bit with my drill. The floor was very absorbent and I had to apply the first coat thin to stretch the kit to cover the whole floor (about 500 sf). Had to do the application with the doors closed since the Cottonwood seeds are flying around and they were starting to float into the garage.

Here's a pic of the first coat.

 

[bajones9181]

Snorvet, did you put on the 2nd coat today? If so how many hours did you wait between coats? If you have more pics please post them. I'm going to be starting my floor tomorrow. Hopefully the overnight lows of 48 degrees don't give me any problems with the epoxy.

 

[snorvet]

Bajones, I dont think the 48 degree nights will be a problem. Its about the same here. I had the heater on for a week at about 70 degrees to dry the rinse before putting down the epoxy. I got bubbles in the epoxy from the warmer concrete emitting air - at least thats what I read on some website. So I think its best if the concrete is at the outdoor temperature. I didnt want to apply the second coat in 16 hours like the directions say due to the bubbles. So I waited until it hardened and I'm going to give it a light sanding before the next coat.

Also dont care for the taupe color - it really looks like gray. So I'm going to get some more flakes and really cover the floor with flakes. I also read that someone did this and then applied a clear coat over the flakes. I'm going to look into the clear coat idea today, sand tonight, and probably apply the second coat tomorrow morning.

 

[bajones9181]

Let me know if you find anything out on the clear coat. I was thinking about putting a UV resistant clear on top since this floor will see a lot of sun in the afternoon hours when the door is open.

From what I gather I thought you would get bubbles (outgassing) only if the epoxy was applied in direct sunlight or if the slab was in the process of warming up. Sounds to me like you already had your slab warmed up and it was cooling off. I read that if you thin your first coat then it will help with the bubble problem. I will call today to verify that.

Did you get any fish-eyes in the areas that had oil spots before?

 

[snorvet]

no problems in the areas where I had the oil spots. Also, it seems like there are far less bubbles along the edges where I used the brush. The bubbles are two different types. One is clusters of 1/16" diameter bubbles in groups about 1/2" diameter (fish-eyes). I have maybe 5 of these clusters where I applied it thicker. The other clusters (hundreds of them) very in size up to 1" diameter and really dont look like bubbles - its probably clusters of microscopic bubbles-unless its pieces of the roller coming off. But I didnt notice any roller fuzz. These bubble bumps are easily sanded down.

I'm going to sand, and then apply the second coat in one of the closets first just to see if the roller is the problem.

 

[bajones9181]

Snorvet, after doing some reading last week I decided to pick up some shorter nap rollers. I picked up a few Pro Classic Mohair blend 1/4 nap rollers from Lowes. They say they are for smooth surfaces and are used for enamels, urethanes and epoxies. Something like this may work better than the 3/8 nap rollers that come with the kit (especially for your 2nd coat). I found a lot of good info on http://www.epoxyproducts.com. I will update my thread late tonight once I get the first coat down and let you know how these rollers worked out.

Quick question - Did you see the bubbles immediately or after it cured?

 

[snorvet]

Bajones,
Bubbles came on immediately. Thanks for the roller advice. I'm going to the hardware store now for a better roller. I picked up 4 packs of Rustoleum flakes today to add to the mix. I'm going to sand first and hopefully get the second coat down tonight.

 

[bmwpower]

For some other good rollers, check out:

http://www.garagejournal.com/forum/showthread.php?t=2222

 

[bajones9181]

Snorvet, I had the same bubble problem you experienced when I applied tonight. I also agree that the taupe looks grey. I posted some pics in my thread. Hopefully you had luck on the 2nd coat. I need some hope!!!