# Garage Floor Epoxy Prep



## PinnacleResidential (Aug 10, 2008)

I know that there aren't a ton of painters that get into epoxy coatings. However, for those that do......

I like to follow the following steps:

Power Wash
Degreaser
Power Wash
Allow to dry 24 hours
Grind all problem areas, oil spots, tire tracks, etc
Muratic Acid Etch
Power Wash
Allow 48 hours to dry w/ Commercial Type Fans (4 of them) and 2 dehumidifiers running
Epoxy (2 Coats)
1 coat High Gloss Sealer

Here's my question... I use a 7" angle grinder when grinding problem areas. The next project I have coming up is like one big problem area. I feel that it would be in my best interest to rent a concrete grinder. Has anyone used one? How difficult / easy is it? How much of a mess should I expect? and finally, Where the heck can you rent one? My local rental place doesn't have one, neither does the depot or lowes. Any ideas?


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## vermontpainter (Dec 24, 2007)

PinnacleResidential said:


> Any ideas?


Find the nearest rental franchise and have one of these bad boys trucked in.


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## PinnacleResidential (Aug 10, 2008)

Tough to use? (I know I shouldn't be asking pricing questions but.....) Any idea on what the cost of rental is? A rough estimate is fine - one, two, three hundred?


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## NEPS.US (Feb 6, 2008)

PinnacleResidential said:


> I know that there aren't a ton of painters that get into epoxy coatings. However, for those that do......
> 
> I like to follow the following steps:
> 
> ...


If it's a simple garage floor then:
Way too much to that system. 
Try H&C Concrete 2 part epoxy and follow their instuctions. $100 per kit and one kit does one standard bay. 
Wash Floor with degreaser
Etch
Mop wash
24-48 hour dry time
apply epoxy ...add in anti slip and sprinkles

I have never had a problem with this system ...no tire lift at all.


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## HomeGuardPaints (Jan 17, 2008)

concrete grinders relatively easy to use, but you can only get within 8 inches of the walls so you will need to use your grinder for the extra.


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## vermontpainter (Dec 24, 2007)

NEP

Not to get off topic, but would you believe me if I told you that I even brush these with my 2" Purdy? I get a sweet cross hatch decorative pattern. I go through alot of knee pads.


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## tsunamicontract (May 3, 2008)

what the heck is that Scott? I know BM just sent out a flier saying they have a concrete grinder for rent. Is grinding that beneficial? 
After you etch with acid you need to neutralize it with something basic. Like soap or baking soda. Why power wash before degreasing. I just sweep it out, hose it down to get it wet and then splash on degreaser and start scrubbing. I wonder if a scrubbing machine (like for floors) would work better and deck brushes? I always squeegee the floor to dry it faster. I like to have one person on the PW and one on the squeegee, gets it super clean and dry really fast. Over night drying, patch (the rustoleum patch is impossible to get smooth with a knife, is there a better tool or a better product to use?), let dry for I think it says another 8 hours, then coat.


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## PinnacleResidential (Aug 10, 2008)

I just get nervous about tire pick up. Since using this system, I have never had the issue. Actually, the first time I did it was to my own garage - New Stuff I like to test myself rather than testing on my client's property. When my floor peeled, I used about 6 coats of stripper to get the old stuff off, grinded the rest off, and used this procedure. I know it seems excessive (I have never seen a label that required all that prep) but it makes my feel warm and snuggly inside knowing I could eat off of that floor before I apply epoxy. 

This H&C stuff, where do you purchase? And do they recommend grinding? The one concrete supplier that is known as the best in my area told me never to trust muratic acid over oil stains - He said better safe than sorry so I have instilled my trust in him and it has paid off. I don't mind the little extra work (I charge by the hour) but am curious about where to get a grinder. I don't need a drive behind (it's just a two car garage) but just a simple walk-behind would work fine.


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## NEPS.US (Feb 6, 2008)

vermontpainter said:


> NEP
> 
> Not to get off topic, but would you believe me if I told you that I even brush these with my 2" Purdy? I get a sweet cross hatch decorative pattern. I go through alot of knee pads.


no sprinkles?


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## PinnacleResidential (Aug 10, 2008)

I wonder if brushing is a benefit because is helps the epoxy get into the pores and rough surfaces in the concrete? You know, like cedar siding and decks. Maybe I'm off base but it seems to make sense


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## PinnacleResidential (Aug 10, 2008)

Like I said, I may be wasting extra time by starting with power washing but it's the method I use because it's what worked for me when I did mine. There is one other thing too, By power washing everything off to begin with, I know what was just a light dirty spot that cleans right up and I know what areas will need special attention.


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## NEPS.US (Feb 6, 2008)

See how civil we are now.......

H&C is available at SW ... they have some good stock colors .. Brick Red, Pewter and a beige. Have you looked into getting a floor surfacer for your powerwasher? I am in the middle of ordering one this week from my SW rep. I have to strip a few garages from another painter who used a crappy latex one part concrete paint....$800 buck for the surfacer. Muralo has a nice kit as well. $75 bucks but no sprinkles or grip included and you need 2 coats. The H&C covers great (1 bay per mixed gallon) with a brush and thick nap 9". By far the best I've used. For $100 a gallon it better be.


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## johnthepainter (Apr 1, 2008)

i always grind them nowdays

ive rented 2 different types of grinders

both have been orbital with different types of heads/attachments

my rental co's charge me $100 for the day (typically $150) for the machine

the heads are wear items and cost an additional $35-$50

the results vary greatly between heads,,,,,,,,the scarifier will do a fair ammount of resurfacing/levelling, and adding a considerable ammount of tooth to the floor

one of the heads does a particularly good job of removing old coatings

i can get within 2-3" of the wall with theses machines

as much as i like to use these machines, i was mesmerized by the shot blasters at a pro show,,,,,,,

check out micro-toppings for concrete finishing, and acid stains also,,,,,,,,,the possibilities are endless


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## timhag (Sep 30, 2007)

NEPS.US said:


> See how civil we are now.......
> 
> .


:thumbsup::thumbup::thumbsup::thumbup: Welcome brother.


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## NEPS.US (Feb 6, 2008)

johnthepainter said:


> i always grind them nowdays
> 
> ive rented 2 different types of grinders
> 
> ...


Hey JOhn ....when you grind them how much of the concrete are you cutting in to? Do you skip all washing steps?


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## johnthepainter (Apr 1, 2008)

i havnt done (and probably wouldnt do if asked) a really greasy floor

the floors i have done have been in good condition (most of them are immaculate)

so i grind them and mop them,,,,,no muratic acid anymore

i used to hit them with muratic, but i dont see the need anymore

i dont remove much concrete, just turn it all nice and powdery, and get it looking uniform, and absolutely no polished/burnished or slick concrete left

the scarifyer head WILL remove some material if you want to,,,,,,,,,you could take a gap/uneven crack with a 1/4" lip, and level it out

i thin my first coat with xylene, and i use a nap designed for epoxy


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## johnthepainter (Apr 1, 2008)

and dont tell the rental company this, but>>>>>>

use all of the weights they provide, and then put a box of tile, or somthing heavy on the top of the machine

maybe even stand on it for a stubborn spot


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## NEPS.US (Feb 6, 2008)

thanks John ....never thought of using a grinder ....i like it


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## HomeGuardPaints (Jan 17, 2008)

grinding is the way to go


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## johnthepainter (Apr 1, 2008)

ive been trying some waterborne 2 part epoxies lately (on ceramic tile)

they seem very tough, pleasant to work with

but the clear bases (muralo) take 4 coats to cover

very tough stuff though

im curious whether anyone uses these for floors, and how they perform


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## tsunamicontract (May 3, 2008)

Do you fill cracks and pits before grinding? How much does it grind off?


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## ewingpainting.net (Jun 2, 2008)

Any one ever use Rust-Oleum floor coating


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## johnthepainter (Apr 1, 2008)

yes, fill cracks and pits,,,

you arent removing much concrete,,,,,,just think of it as sanding

just like how woodwork that has mill glaze, and wont accept stain until the polished/mill glazed has the pores opened up with some sand paper

your just removing the hard troweld/polished look,,,,and giving it some tooth


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## tsunamicontract (May 3, 2008)

Right on, Right on. I just did a garage floor and the dam patch flashed and did not smooth out so a good "sand" for the whole thing would probably just look great. What do you use to patch John?


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## ibsocal (Apr 17, 2007)

PinnacleResidential said:


> I know that there aren't a ton of painters that get into epoxy coatings. However, for those that do......
> 
> I like to follow the following steps:
> 
> ...


Look man U are using way to many steps and time to do this.scrub clean oily areas yes but dont need the pressure wash mess/wait dry time.dry out with a propane (large)blow torch local areas .blastrac makes a easy to use shotblaster 110v and grinders with diamond wheels also edge grinders they all are super easy to use and kick a$$.any painter with skills can do it.patch and repair after areas cleaned then add profile to repaired areas.the whole job can be done sometimes in a day and maybe + 1/2 day if u flaked and need to clear coat.they dont make much dust at all if U use the dust collector they come with.edco has good grinders as well but i dont know your area but in san diego most major rental centers carry one or the other.


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## ewingpainting.net (Jun 2, 2008)

So I take it no one has used Rust Oleum floor coating before.


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## vermontpainter (Dec 24, 2007)

ewingpainting.net said:


> So I take it no one has used Rust Oleum floor coating before.


 
Back in the early 80s we did. Buddy of mine had a 79 Capri with a 302, basically a poor mans mustang, with lettered tires and mags. He kept swapping out quarter panels and every time, we would take it in the garage and spray them out with Rustoleum. I always remembered the dusty dryfall on the floor. As an adult, I have sprayed out many a residential concrete floor with the stuff. It works best if you have a can in each hand spraying in overlap patters to avoid cloudy spray can patterns. Occasionally, if it is a big job, I will spray like 20 cans into my pump sprayer, cut it with muriatic acid, acetone and penetrol and spray it out of there. This way you can integrate the etching into the finish steps. I am all about multi tasking. Its a great floor product, ewing. Glad you asked.


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## johnthepainter (Apr 1, 2008)

tsunami,,,i use a self leveling floor patch,,,,it WILL flash under one coat,,,but i 2 coat all of my epoxy jobs

ive never used the rustoleum brand flor epoxy,,,,,,i see a one component system they offer now

ibsocal >>>the blastrac stuff is excellent equipment,,,,,if anyone is looking to rent concrete prep equipment, look for blastrac


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## ewingpainting.net (Jun 2, 2008)

Ver.
I have tried the double spray can method before but I tend to get a heavy over lap. So I'm sticking to the single action.

BTW, when spraying the cans in your sprayer. How do you keep from falling over? Every time I've tried it I get light head and end up waking up on the ground with a huge head ache, even with a respirator on.:notworthy:


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## PinnacleResidential (Aug 10, 2008)

Ok, rented the floor grinder. Grinder worked excellent but was pricey. It was a single head walk-behind model with an attachment for a vacuum. Total price of Grinder & Pulse Vac for the 1 Day rental was $135. Then, of course, I had to buy the diamond head attachment - $125. Total with tax was over $275. I started grinding around 10am and was done by 1:30 - it went that quick. Then, I put the acid on the floor (don't know that I needed to but I already had some left over from the last floor so I did just for good measure. Then Power Washed and squeegied the water out. I've got exhaust fans and dehumidifiers in there running tonight and will be laying the floor tomorrow........

Probably will be grinding from now on since it did such a great job and left a nice rough surface to adhere to.


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## ibsocal (Apr 17, 2007)

PinnacleResidential said:


> Ok, rented the floor grinder. Grinder worked excellent but was pricey. It was a single head walk-behind model with an attachment for a vacuum. Total price of Grinder & Pulse Vac for the 1 Day rental was $135. Then, of course, I had to buy the diamond head attachment - $125. Total with tax was over $275. I started grinding around 10am and was done by 1:30 - it went that quick. Then, I put the acid on the floor (don't know that I needed to but I already had some left over from the last floor so I did just for good measure. Then Power Washed and squeegied the water out. I've got exhaust fans and dehumidifiers in there running tonight and will be laying the floor tomorrow........
> 
> Probably will be grinding from now on since it did such a great job and left a nice rough surface to adhere to.


:thumbsup:grinder good.:detective:full on wash and acid no longer required with modern technolgy and machinery.shot blaster works real good leaves a great anchor tooth profile.U could have just grinded,vacuumed and painted in same day + broadcast flakes if that is what was required then scrape and clear coat the next day,done.


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## Safety Guy (Jul 19, 2007)

We have not acid etched in at least 10 years. We shot blast and hand diamond grind any edges or around equipment. The Blast-trac equipment is awesome!! A bit pricey to buy but the labor saved more than pays for it after a few big jobs. If you are ust doing garga floors rental probably makes more sense than buying.


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## Bender (Aug 10, 2008)

Interesting, I haven't done a floor in 3 or 4 years but the last time we did, we acid etched. I will try blasting next time.
I really like SW Armorseal1000. Is this still one of the better floor coatings?


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## Safety Guy (Jul 19, 2007)

Bender said:


> Interesting, I haven't done a floor in 3 or 4 years but the last time we did, we acid etched. I will try blasting next time.
> I really like SW Armorseal1000. Is this still one of the better floor coatings?


We use alot of the Armorseal 650, I'm not sure we have used the 1000?? Most of the time it is written in the spec what we have to use. SW has a new floor coating out that we have not used yet that looks pretty interesting for newer and high moisture slabs call Aquarmor.


We seldom do garge floors but generally if we put an epoxy down where there is the possibility of U.V damage we topcoat with a urethane. Anyone else do this?? Any problems with the sunlight degrading/fading your floors???


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## Bender (Aug 10, 2008)

From SW website, 


ARMORSEAL® 1000 HS EPOXY 

ArmorSeal 1000 HS is a high solids, heavy duty, two-component, catalyzed, polyamide epoxy coating formulated for demanding marine and industrial requirements. This dries rapidly to a tough, high gloss finish with excellent resistance to alkalies, abrasion, corrosion, and chemical attack.



ARMORSEAL® 650 SL/RC SELF-LEVELING EPOXY 

ArmorSeal 650 SL/RC Self-Leveling/Recoatable Epoxy is a two-component, high performance floor system that provides a high gloss, seamless, hygienic surface that is extremely hard wearing and durable. The coating can also be applied to provide a nonslip texture. This product may be topcoated if required.


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## Formulator (May 28, 2008)

Tsunami,

How did that epoxy shield pro work out?

Carter


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## tsunamicontract (May 3, 2008)

Real slick Carter, HO were very pleased. It really could have used a high building and leveling primer coat maybe or just two coats of it. Shoulda worn my respirator, I had a little cold for 3 days after it. Just the one coat of paint looked pretty uneven gloss wise but when I clear coated it (which covered barely two pro kits on a large area) it looked great, I assume it will help lock down the flakes too. They want me to do their screen porch now. Wish I had thought about grinding though, their concrete was pitted some. I have tons of pictures, I will post some once I get them sorted though and resized for the web.
Thanks again Carter.


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## vermontpainter (Dec 24, 2007)

Nice to see you two have mended the fence.


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## tsunamicontract (May 3, 2008)

vermontpainter said:


> Nice to see you two have mended the fence.


but how much should we charge to paint it?


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## vermontpainter (Dec 24, 2007)

tsunamicontract said:


> but how much should we charge to paint it?


Mending it is the hard part. Painting it is cake. Form can bring some cans.


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## tsunamicontract (May 3, 2008)

I still have a huge box, I am set for a while


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## Safety Guy (Jul 19, 2007)

tsunamicontract said:


> I still have a huge box


You sound like my wife:whistling2:


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## spectrum (Apr 27, 2007)

*Spectrum*

We do alot of residential garage floors with epoxy throughout the year. The one thing I learned the hard way is how serious you need to take the preparation work. After many failures, we have learned to abandon powerwashing and acid etching as a means of preparing the floor. Shot blasting and edge grinding is the only way to go. With shot balsting, the floor will be clean and dry, without soaking it down and waiting for it to dry. The PH won't be off either. You can shot blast and edge grind a 2 bay garage in about 4 hours and then apply the first of a two coat catylyzed acrylic (water borne) epoxy finish that same day. Second coat on day two. We offer color flakes and a clear coat as an upgrade, using a catylyzed urethane as the final non yellowing wear coat over the flakes. Great system! You need to either buy a small shotblaster or find someone to come in and blast for you. The entry level equipment costs about $12, 000. We charge $1.00 PSF for blasting smaller residentail jobs here in Northern NJ. All this assumes that you are not stripping heavy layers of old peeling paint from the floor.


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## tsunamicontract (May 3, 2008)

spectrum said:


> You need to either buy a small shotblaster or find someone to come in and blast for you. The entry level equipment costs about $12, 000. We charge $1.00 PSF for blasting smaller residentail jobs here in Northern NJ. All this assumes that you are not stripping heavy layers of old peeling paint from the floor.


What about water blasting, hooking up a sand nozzle to your PW? Still gets the floor wet but you can add it to your PW for about $150. Does that work?


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## Safety Guy (Jul 19, 2007)

tsunamicontract said:


> What about water blasting, hooking up a sand nozzle to your PW? Still gets the floor wet but you can add it to your PW for about $150. Does that work?


A PW with sand injection will not give you near the blast profile a shotblaster will. I don't think it would work but have never tried it.


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## CApainter (Jun 29, 2007)

I've used Blastrac shot blast 120V that has a splitter to draw from two different circuits. This is convenient when you don't have access to 220V.


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## Formulator (May 28, 2008)

ewingpainting.net said:


> So I take it no one has used Rust Oleum floor coating before.


 
Ewing, 

The Epoxy Shield Pro is almost a foolproof 2 part epoxy system. If you want to sample it, let me know. The waterborne is very good, but requires more prep. I have some pics in the projects section of my parents garage where I used the Epoxy Shield Pro if you are interested in looking at them.

Carter


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## Formulator (May 28, 2008)

johnthepainter said:


> tsunami,,,i use a self leveling floor patch,,,,it WILL flash under one coat,,,but i 2 coat all of my epoxy jobs
> 
> ive never used the rustoleum brand flor epoxy,,,,,,i see a one component system they offer now
> 
> ibsocal >>>the blastrac stuff is excellent equipment,,,,,if anyone is looking to rent concrete prep equipment, look for blastrac


 
We don't have a one component for garages. We do have a 1k for basements. I would in no way recommend the 1 part systems. We generally find that the best 1 part system is not even as good as a bad 2 part system.


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## bikerboy (Sep 16, 2007)

Safety Guy said:


> You sound like my wife:whistling2:


 
Your wife has a huge box? 

(Kidding!)


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## Formulator (May 28, 2008)

Safety Guy said:


> We use alot of the Armorseal 650, I'm not sure we have used the 1000?? Most of the time it is written in the spec what we have to use. SW has a new floor coating out that we have not used yet that looks pretty interesting for newer and high moisture slabs call Aquarmor.
> 
> 
> We seldom do garge floors but generally if we put an epoxy down where there is the possibility of U.V damage we topcoat with a urethane. Anyone else do this?? Any problems with the sunlight degrading/fading your floors???


UV WILL damage epoxy. That is why it is NOT suitable for anyplace that gets constant sun exposure. I'm not into our high performance products much, but I don't see how a urethane over top will prevent the UV damage since I would think that it would just yellow the epoxy underneath.


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## Formulator (May 28, 2008)

spectrum said:


> We do alot of residential garage floors with epoxy throughout the year. The one thing I learned the hard way is how serious you need to take the preparation work. After many failures, we have learned to abandon powerwashing and acid etching as a means of preparing the floor. Shot blasting and edge grinding is the only way to go. With shot balsting, the floor will be clean and dry, without soaking it down and waiting for it to dry. The PH won't be off either. You can shot blast and edge grind a 2 bay garage in about 4 hours and then apply the first of a two coat catylyzed acrylic (water borne) epoxy finish that same day. Second coat on day two. We offer color flakes and a clear coat as an upgrade, using a catylyzed urethane as the final non yellowing wear coat over the flakes. Great system! You need to either buy a small shotblaster or find someone to come in and blast for you. The entry level equipment costs about $12, 000. We charge $1.00 PSF for blasting smaller residentail jobs here in Northern NJ. All this assumes that you are not stripping heavy layers of old peeling paint from the floor.


 
You're all 100% correct. If you can AVOID acid etching and grind instead then you probably should do that. Acid will completely stop the reaction and you can end up with putty or a few soft spots. 

We have had people add the citric acid packet to the epoxy shield thinking it was anti-skid. That completely stopped the reaction and they were in a world of hurt.


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## Safety Guy (Jul 19, 2007)

bikerboy said:


> Your wife has a huge box?
> 
> (Kidding!)


That was kinda the joke I was making, I wondered if anyone would get it:whistling2:


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## MAK-Deco (Apr 17, 2007)

Safety Guy said:


> That was kinda the joke I was making, I wondered if anyone would get it:whistling2:



oh we got it


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## Safety Guy (Jul 19, 2007)

Formulator said:


> UV WILL damage epoxy. That is why it is NOT suitable for anyplace that gets constant sun exposure. I'm not into our high performance products much, but I don't see how a urethane over top will prevent the UV damage since I would think that it would just yellow the epoxy underneath.


We use a tinted urethane not clear. The epoxy would yellow underneath with a clear coat.


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## Bender (Aug 10, 2008)

Anybody ever experience outgassing


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## Safety Guy (Jul 19, 2007)

Bender said:


> Anybody ever experience outgassing


Outgassing and hydrostatic pressure are my favorites!!! I have learned to aask alot of questions with regards to moisture barrier, when it was poured and slab thickness before I even think about putting down a "standard" floor. I also use up alot of calcium chloride test kits.


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## spectrum (Apr 27, 2007)

We experienced a nightmare of outgassing on a huge, old concrete floor that had been used to keep the animals (giraffes I think) for Ringling Bros Circus during the winter. 

Our Calcium Chloride tests revealed nothing because the outgas was _dry._

We ended up sanding over the millions of dry epoxy air bubbles with our commercial floor sanding machine and opening them up to a crater. When we stuck a pin in the crater, we realized the "hole" went all the way to the concrete subsrate. Outgassing for sure. Then, we made a "paste" with silica flour and epoxy primer. On our hands and knees with small rubber squeegees we filled every crater with our home made epoxy paste. 
A light sanding and another full overcoat with 100% solids epoxy and we were DONE . It looked like a dinner plate when we finished. but I lost my shirt on that one.


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## NACE (May 16, 2008)

Outgassing can occur when the 100% solids heats up and expands trapped air in the concrete that expands and come to the surface. A porcupine roller is used to go over the curing epoxy when the bubbles are noticed. Sometimes adding some Xylene to the epoxy will help a little, but mostly you have to watch for it and back roll the epoxy with the porcupine cover. You can sometimes minimze the effect if you prime the floor first. The primer acts as a barrier and marry's the 100% solids to the primer, while the primer is "in" the floor not "on" the floor. It is important to do a moisture test BEFORE you paint and keep a record of it. Three important tests are 1, Curing compounds (new concrete) Test with hydrochloric acid. Insure that the acid bubbles and reacts, and just does not sit there. 2, Moisture content. There are many ways to do this. Either use the simple test ASTM E1907-06a, plastic sheeting method. a 2' x2' section of concrete is taped over with 3 mil plastic and evaluated after 24 hours to see if the concrete darkens. Concrete is a ridgid sponge and will accept a coating system if the concrete is stable at <4% moisture content. Non destructive concrete moisture encounter, (moisture meter, not the 2 nail method with wood meters) or anhydrous calcium choride test. (Good for applications of over 1,000 sq ft) If moisture content is greater than 4%, you risk hydrostatic pressure pushing the film off. Water tables change throughout the year, so it is important to observe not only the date of installation, but exterior drainage as well. 3, Surface profile. Concrete should have a minimum surface profile of 80 grit sandpaper to accept a coating system for most light commerrcial and residential applications. Grinding is the best method. Acid does not create a proper profile and leaves a acid pH that must be neutralized. The Internationl Concrete Repair Institute www.icri.org, has standards for concrete surface profiles. For garage floors, it should be between 60 and 100 grit.
A clear acrylic urethane should be used over epoxy is there is UV exposure as the epoxy will chalk and yellow. This is only an aesthetic issue, not a durability issue. Acrylic urethane are prone to plastisier migration from compounds in both the tires and the urethanes. Some tires, especially high performance tires from Porsche, Audi, MB, BMW will yellow, stain, or ghost a tire imprint into the urethane. This is normal and cannot be eliminated. It can be minimized by using an aggregate or with chips so the the tires do not lay flat on the coating. Floors can be a disaster, and in my opinion should be priced higher because you eventually are going to get a call back or failure, and you should have some margin to cover the repair costs. If you know the prep steps and what to look for, you can have a 90+% success rate, but 10% fail and it is not the paints fault or your fault, they just fail.


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## ewingpainting.net (Jun 2, 2008)

NACE said:


> Outgassing can occur when the 100% solids heats up and expands trapped air in the concrete that expands and come to the surface. A porcupine roller is used to go over the curing epoxy when the bubbles are noticed. Sometimes adding some Xylene to the epoxy will help a little, but mostly you have to watch for it and back roll the epoxy with the porcupine cover. You can sometimes minimze the effect if you prime the floor first. The primer acts as a barrier and marry's the 100% solids to the primer, while the primer is "in" the floor not "on" the floor. It is important to do a moisture test BEFORE you paint and keep a record of it. Three important tests are 1, Curing compounds (new concrete) Test with hydrochloric acid. Insure that the acid bubbles and reacts, and just does not sit there. 2, Moisture content. There are many ways to do this. Either use the simple test ASTM E1907-06a, plastic sheeting method. a 2' x2' section of concrete is taped over with 3 mil plastic and evaluated after 24 hours to see if the concrete darkens. Concrete is a ridgid sponge and will accept a coating system if the concrete is stable at <4% moisture content. Non destructive concrete moisture encounter, (moisture meter, not the 2 nail method with wood meters) or anhydrous calcium choride test. (Good for applications of over 1,000 sq ft) If moisture content is greater than 4%, you risk hydrostatic pressure pushing the film off. Water tables change throughout the year, so it is important to observe not only the date of installation, but exterior drainage as well. 3, Surface profile. Concrete should have a minimum surface profile of 80 grit sandpaper to accept a coating system for most light commerrcial and residential applications. Grinding is the best method. Acid does not create a proper profile and leaves a acid pH that must be neutralized. The Internationl Concrete Repair Institute www.icri.org, has standards for concrete surface profiles. For garage floors, it should be between 60 and 100 grit.
> A clear acrylic urethane should be used over epoxy is there is UV exposure as the epoxy will chalk and yellow. This is only an aesthetic issue, not a durability issue. Acrylic urethane are prone to plastisier migration from compounds in both the tires and the urethanes. Some tires, especially high performance tires from Porsche, Audi, MB, BMW will yellow, stain, or ghost a tire imprint into the urethane. This is normal and cannot be eliminated. It can be minimized by using an aggregate or with chips so the the tires do not lay flat on the coating. Floors can be a disaster, and in my opinion should be priced higher because you eventually are going to get a call back or failure, and you should have some margin to cover the repair costs. If you know the prep steps and what to look for, you can have a 90+% success rate, but 10% fail and it is not the paints fault or your fault, they just fail.


Great post!


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## Bender (Aug 10, 2008)

Damn NACE!
Did you google that


Outstanding info:thumbsup:


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## Safety Guy (Jul 19, 2007)

Great Post, pretty much sums it up. I like the 10% failure rate comment. I would love to have the time to go back and review what our failure rate is overthe last 10 years.


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## daren (Jul 5, 2008)

Bender said:


> Anybody ever experience outgassing


I sometimes have outgassing after mexican food.

sorry I couldn't let that pass with out a pun.


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