Need Expert Help

[jimshaw]

We are a company that epoxies garage floors. For years have been etching the floor with acid to create a roughness on the face on the concrete for the epoxy to adhere to.

We would love to stop using acid for another method and hoping that high pressure washers might do the job.

Would a washer with a turbo head, 4000 PSI and possible 4 GPM be able to create a slight roughness on the surface of a concrete floor so that an epoxy paint would bond? If so, would it take oil off the surface.

There are other methods that work well such bead blasting but the machines cost about $8,000 and when you need three of four, the cost would be too great.

If a washer would work, how much PSI and GPM's would it take?

 

[Gwas]

You would need more gpm's for what you are doing. You also do not need to pay that much for a unit. I can steer you in the correct directon for machines. A heavy degreaser will help with the oil...

 

[Larry L.]

How are you appling and removing the acid now,are you doing the work or having it done?

I think the turbo will be to slow,making your bids higher.

 

[Mark]

Jim,

If you are near the Sacramento area, give me a call, I can demonstrate a 5 GPM 5000 PSI pressure washer for you.

 

[jimshaw]

Right now the acid is worked into the cement, let sit then washed out leaving the cement slightly scared for bonding. We do the etching ourselves.

Time is important but not as important as making sure there is a good bond between the cement and the epoxy.

What has been mentioned is not enough GPM's. Is the 4000 PSI good enough but the GPM's should be higher??

 

[Mark]

If the pressure washer is powered by a 13 HP engine you are not getting a full 4 GPM @ 4000 PSI probably closer to 3.5 GPM or less maybe.

The machine I referred to is a Full 5 GPM @ 5000 PSI I think that will work for you and would be happy to demonstrate it at my shop on some old concrete.

I think 4 gpm or less at 4000 PSI with a Turbo nozzle would be too slow.

You might want to try renting a 5000 PSi unit if you are not close enough to Sacramento for a demo.

Call me Monday I can offer suggestions on where you might find a 5000 PSI rental unit.

5 GPM 5000 PSI powered by 24 HP Honda

 

[jimshaw]

Mark

A big thanks. I will touch base with you Monday.




Jim

 

[Larry L.]

Jim in no way am I trying to talk you out of trying the turbo,only trying to understand your problem.

I know you want to get away from the acid,the turbo will not give the bond you need for garage floors for the epoxies.Even though the turbo will rough up the surface you will still need to boil the bottom of the small craters the turbo makes for a good bond.Hotwater would help remove the oil and dirt from the small ceaters which means you may need a different type burner to run the powerwasher indoors.

I don't think you'll get the bond from a turbo as you now do with acid.There may be a faster and better way to apply the acid and a surface cleaner would speed up the job.

 

[jimshaw]

Larry

Right now we don't use a pressure washer. We pour the acid on the ground, buff it in and wash it off.

I was hoping that we could eliminate the acid with high pressure washing. I am not really concerened with oil because over 90% of our business is in new homes with new concrete. If we do have a floor with oil, we use degreasers to remove. If there is too much oil, we turn down the job.

I was thinking "turbo" only because I have heard that it might speed up the washing???????

My only concern is that a washer could produce a floor that would bond epoxy.

 

[Larry L.]

Understand,,

After you learn how to use the turbo its a fairly fast tool on new concrete,on new concrete a surface cleaner(speed) may rough up the surface enough for a good bond without the splash back you'll get from a turbo.

On jobs that you need to acid wash ask Mark to show you the 12v pumps,they're faster than pouring on and saves chemicals.

 

[jimshaw]

Larry

Thanks for all the info.

It is a major decision to make, acid vs. high pressure washer and it seems to me from what I hear is:

On new concrete a high pressure washer can scar the concrete enough to produce a bond with epoxy. A turbo will help speed things up but a surface cleaner attached to the washer will possible do an over all better job eliminating a lot of over splasing with water.

The washer should be in the 4000-5000 PSI range but does how much GPM's it produces make much different??

For older concrete with a lot of oil and scum on top, acid will possible work better.

Is this a fair evaluation????


Jim

 

[Larry L.]

Yes,,

The more gpm the faster you can go,on new concrete a cold water rig will work ok for roughing up the surface.

 

[jimshaw]

Larry

I really appreciate the help you have given me.

I'll touch base with Mark Monday.


Jim

 

[davidwil]

Jim,

Just today I was researching how to go about staining garage floors. Talked to a concrete supplier company about some stains they handle that includes the acid in the stain. Their samples looked great and the process seemed much easier and shorter than most that I have come across. Especially since some processes take 3 work days.

Anyway, one thing that was mentioned about the etching process was that the acid dissolves the portland cement in the concrete and makes the concrete porous so as to make the coating bond properly. Would the etching from a pressure washer create the same effect? Or would water pressure only "rough up" the surface? I certainly don't have the experience in this kind of work but after doing some research and reading all the post here that question stuck in my mind.

If you don't mind telling, what system or products do you use?

 

[Bill B]

To summarize the above, esp. Big Boy's replies, stick with the acid. I'd spend my time optimizing application and handling the acid as opposed to trying to brute force prepare using a PWer.

 

[Bill B]

I forgot to ask. What do you charge per sq ft for applying the epoxy? What % of price is the epoxy itself?

Also, tell me more about staining concrete. Sounds interesting.

 

[DanKes]

http://www.lsepoxies.com/Organo-etch.html

Here's an acidic etch product with a citris odor and no muriatic acid in it. It may be a little safer that what you are presently using.