Hey guys. I've been doing some research on epoxy floor coatings and came across this great site. I had a question about using muriatic acid to etch the floor. I've never used the stuff but from what Ive heard it's pretty nasty. When I'm washing this acid mixture out of my garage what will it do to my sealed asphalt driveway and grass? The last thing I want to do is ruin my sealer or kill my grass. Thanks for any help!
Muriatic Acid Question
- Thread starter AMarkham
- Start date
LegacyIndustrial
ALLIANCE MEMBER
You will not be using this material at full strength. Read the label for the dilution ratio, call the manufacturer if it is not listed. Also... wear the proper PPE.
It may hurt the grass but should be ok on the driveway if you flush it with a lot of water.
AlphaGarage
Well-known member
Muriatic acid is one of the most hazardous products in the hardware store, but after you're done etching it isn't that bad.
You'll probably dilute it with water, start with a test 2 parts water to 1 part acid, when applied it should sizzle but not smoke.
On the concrete it works by interacting with the calcium in the concrete, that interaction cuts its strength.
You leave it on the concrete, as it sits it interacts with the oxygen and that weakens it.
You should neutralize it with a baking soda/water mixture, that further weakens it.
Finally you rinse it off with running water, which weakens it even more.
So in the end it's not near as strong as it was in the bottle. BUT it still may have some kick, so try divert the run off away from landscaping. If that's difficult to do, then consider a 2nd baking soda application before the rinse and rinse with lots and lots of water.
As always be sure to carefully read package instructions and warnings.
You'll probably dilute it with water, start with a test 2 parts water to 1 part acid, when applied it should sizzle but not smoke.
On the concrete it works by interacting with the calcium in the concrete, that interaction cuts its strength.
You leave it on the concrete, as it sits it interacts with the oxygen and that weakens it.
You should neutralize it with a baking soda/water mixture, that further weakens it.
Finally you rinse it off with running water, which weakens it even more.
So in the end it's not near as strong as it was in the bottle. BUT it still may have some kick, so try divert the run off away from landscaping. If that's difficult to do, then consider a 2nd baking soda application before the rinse and rinse with lots and lots of water.
As always be sure to carefully read package instructions and warnings.
Thanks guys. Anybody here ever used Seal Krete Clean-N-Etch instead of a muriatic acid mix? Here is a link:
http://www.sealkrete.com/clean_n_etch.htm
http://www.sealkrete.com/clean_n_etch.htm
GirlnAgarage
Well-known member
Get it on there, do what you need to get the floor cleaned then rinse well and you'll be fine. It'll probably pull off any paint though.
I've used it a number of times for some gunsmithing projects and it'll be fine on steel. Again, rinse well.
Harley Guy
Member
AMarkham: I laid down epoxy on my garage late last summer. I poured the muriatic acid full strength on my 30 YO concrete floor. It worked great, I used a wire brush on the end of a pole to scrub it in. I have a sealed asphalt driveway also. The only problem is the acid takes a thin layer of concrete off (of course). When i rinsed it out the door it left a fine white coating on my black asphalt. I washed the driveway many times it still has a chalky look to it. Not sure how i could have prevented it. I will have it resealed this summer.
I thought I would just throw this out there for those whom may not know this. Muriatic acid is dilute hydrochloric acid (HCL). HCL is extremely corrosive, that's why it's diluted with water (and used as muriatic). Be careful with that stuff! 
Sam Navarro
Member
The most important things to remember when using muratic acid is that it only works upon first contact. The way that I tell customers to apply it is in a pump up sprayer working in circles, do not mop it on. Also PLEASE make sure that you neutralize it atleast twice before coating. If you have any more questions please let me know.
Cheers,
Sam
832-618-0447
Cheers,
Sam
832-618-0447
i have used muriatic acid for lots of stuff at work (we get it free from a contract with chemical supplier) it is realy bad stuff if you get it in places you do not want it. a spray is a good idea as stated befor but you should get a cheap throw away or a good one with a PVC internal parts, the prayers we get only last one use then the isides of the pump and sprayer valve are gone. if it was me i would use the stuff right out of the jug, spray half let set for the time to pound a beer rinse and repeet on other half. as long as you over rinse every thing and dont breath the fumes you will be fine. you might also want to think about other stuff in the garage that may need to be coverd or set in a differnt room for the day.
4.0 Rambler
Well-known member
Another way to spread the acid water mix is with a plastic watering can. Caution don't use a gavenised one. Cheaper then a sprayer and will last for more then 1 job.
PhatTractor
New member
- Joined
- Feb 3, 2011
- Messages
- 3
Water down your grass and asphalt before you use the acid, this will help reduce any of the damage from spillover. Also dilute the acid with water.
pima67
Well-known member
Let me 2nd, 3rd, 4th and 5th what Sam N. said: use a sprayer. I tried a sprinkler can but it didn't give even coverage and etch. I had to redo it using a poly sprayer.
Always add acid. Never add water to acid add the acid to the water. Don't use it straight on concrete. It will leave unwanted contaminates behind as it etches and becomes PH neutral.
Most times you will find a 30% or so + or - 10% will work. Plan on having enough room in the mixing container to hold a 50/50 mix with enough room to tune a bit. this gives you some freeboard.
One way to mix acid for etching. YMMV. Add some acid to the water and test. Test by dripping the mix on the concrete. You want to see a strong bubbly white fizz with little if any white smoke. Too strong will be a light to fully yellow fuzz with white smoke. Too weak will be little fizz. Keep adding more acid a little at a time until you get to the active white fizz level. The acid will loose its ability to etch as it works and combines with the base in the concrete. After a while you will have a salt water of sorts. It is important to wash this solution off. Have a water hose with a lever type sprayer ,ready nearby at all times to wash any acid or mix that gets where it is not intended, like on you.
Most times you will find a 30% or so + or - 10% will work. Plan on having enough room in the mixing container to hold a 50/50 mix with enough room to tune a bit. this gives you some freeboard.
One way to mix acid for etching. YMMV. Add some acid to the water and test. Test by dripping the mix on the concrete. You want to see a strong bubbly white fizz with little if any white smoke. Too strong will be a light to fully yellow fuzz with white smoke. Too weak will be little fizz. Keep adding more acid a little at a time until you get to the active white fizz level. The acid will loose its ability to etch as it works and combines with the base in the concrete. After a while you will have a salt water of sorts. It is important to wash this solution off. Have a water hose with a lever type sprayer ,ready nearby at all times to wash any acid or mix that gets where it is not intended, like on you.
kywildcat
Well-known member
Thanks for the Info Vice!!
slip knot
Well-known member
Dont want to come across as the GJ safety council here BUT Muriatic is some fairly strong stuff. at the very least you need to wear some acid goggles to protect your eyes. I'd also recommend gloves and rubber boots and clothing that your not concerned about getting holes in. and use lots of ventilation.
BTW I found muriatic works great for cleaing rusty tractor carbs. I work on older ford tractors and they have cast iron carbs, any water that gets in there sets up rust like crazy. a few minutes soaking in muriatic and it looks brand new.
BTW I found muriatic works great for cleaing rusty tractor carbs. I work on older ford tractors and they have cast iron carbs, any water that gets in there sets up rust like crazy. a few minutes soaking in muriatic and it looks brand new.
I read on the bottle I got that is works great as a fertilizer in moderation and it has the properties of fertilizer that they make bombs from. I cant remember, it starts with Hyxxxx something. I have handled high concentrate Miratic acid alot at a chemical plant I worked at for many years and it is some bad stuff if your not careful. I have seen it eat through metal over time. I would definitely wear eye protection and old clothes.
Read and Follow the instructions and life will be good.
I used the Muriatic Acid to remove ATF and oil from my carport when trying to
clear base housing. The stuff I purchased was touted as swimming pool cleaner.
I used it straight from the container (a plastic bottle) pouring it on the floor. I then used a broom to squeegee the floor. Worked fine, last a long time...
I used the Muriatic Acid to remove ATF and oil from my carport when trying to
clear base housing. The stuff I purchased was touted as swimming pool cleaner.
I used it straight from the container (a plastic bottle) pouring it on the floor. I then used a broom to squeegee the floor. Worked fine, last a long time...
This is a great thread for those, like me, who are about to etch their slab prior to using an epoxy. In other posts I've read that the acid etch actually makes your concrete slab weaker. That seems to be an extreme view since the muric acid is diluted and only comes into contact with the surface concrete.
Can anyone debunk this, or elaborate so that I can keep it in perspective?
Thanks.
Can anyone debunk this, or elaborate so that I can keep it in perspective?
Thanks.
NextCoatings
Member
Acid etching is designed to soften the surface to allow for better penetration of coatings. Most home owners will never use their floor enough for it to matter. If you don't want to deal with acid and want the best prepped surface, you can go to your local equipment rental store and rent a floor grinder and knock it out in a couple of hours. A scored surface will give you better adhesion and will also bring to life any weak or damaged areas that need to be addressed.
steel 35
Well-known member
johnson1975
Well-known member
bringing up old thread ....
I am about to seal my concrete floor in my pole barn ( 30x40). The barn is about 6 months old and I have been very careful to keep floor clean. Concrete does have some areas with dirt and some areas where rubber tires have left marks on the floor.
I was planning on pressure washing concrete - however I am curiuos if the etching will clean the concrete during this process? If so - It will be much easier to simply rinse the floor VS trying to pressure wash it.
thoughts?
I am about to seal my concrete floor in my pole barn ( 30x40). The barn is about 6 months old and I have been very careful to keep floor clean. Concrete does have some areas with dirt and some areas where rubber tires have left marks on the floor.
I was planning on pressure washing concrete - however I am curiuos if the etching will clean the concrete during this process? If so - It will be much easier to simply rinse the floor VS trying to pressure wash it.
thoughts?
AlphaGarage
Well-known member
Muratic acid will not necessarily clean the floor. It's not like in the movies where everything acid comes in contact with goes up in a whiff of smoke. Acid has no effect on many things, including dirt, grease, and oil.
I would try cleaning any heavy stains, pressure wash, etch, pressure wash.
I would try cleaning any heavy stains, pressure wash, etch, pressure wash.
Edger
Well-known member
My guess is that it will ruin your grass and stain your driveway. You may prevent that if you neutralize it, wet it and wet vac it up before rinsing. Hire a water blaster too and use a detergent on the sealed drive every 15 mins to wash off the residue while you are blasting the floor to rinse it.
Elite Crete Australia
Active member
If you diamond grind the floor you can do away with the acid etching process. You can rent the tools if you don't already own them.
johnson1975
Well-known member
I will look into renting the equipment and compare my options.....
LegacyIndustrial
ALLIANCE MEMBER
Concrete begins to neutralize the acid immediately.
Unless you are shooting the acid out of a fire hose it shouldn't do too much harm.
The baking soda is a good fail-safe measure.
Unless you are shooting the acid out of a fire hose it shouldn't do too much harm.
The baking soda is a good fail-safe measure.
Neighbor and me are both doing our floors at same time (same builder of homes at same time). I used the etching acid solution from Sherwin Williams - phosphoric acid-based etcher and he used muratic acid. We both had same results and chalky finish which we used a power washer to remove. I did paint half my garage tonight with the Shield Crete (and flakes) and will now add the clear glaze to seal it as I think i could have probably rolled it a bit heavier in places and after all this work I want to protect it.