Why do I keep etching driveways?

I have a 4400 PSI, 4.2 GPM machine. I have a 16in Whirl-a-way with 25030, outputting 2000 PSI (checked with pressure gauge). I don’t move overly slow. What am I doing wrong? I don’t understand. Any help would be appreciated. Thank you.

That doesn’t look etched, 2000psi is really low pressure even for residential concrete, looks more like the typical surface cleaner “stripes”… get some tips to bump up to 2500/2700 psi.

Thats one of your problems, move slower, overlap a bit, and go perpendicular (or do two passes in different directions) to the line of sight. Are you pre-treating? How about post-treating? What % SH are you using?

3% Post treat, lines still there. I did use 25025 and go slow, but then this happened:
I changed to 25030 and tried to go faster.

What percentage are you pre-treating with?

Not pre treating

how many nozzles are on your SC? It matters if it is 2 or 4 when selecting nozzles.

If you are running your surface cleaner and see grey, that is cream coming off and that is etching. If there is no grey runoff then it is likely that you are going too fast or not rinsing enough.

Watch racer’s SC video, tons of useful info on it. I almost never pre and post treat. I hit it with the backpack blower, then I apply my HW mix and get it wet, let it sit a minute, then run my SC. If the drive is drying I give it a shot again before the SC hits it.

Thats the issue… put that 3% down first, then surface clean with overlapping passes… you may still need to go vertical and then horizontal or in a circular motion to avoid some stripes, anything thats left hit with 1ish% post treat and don’t rinse it off.

So why did the 3% not work?

I also had another driveway, same street as the second picture I sent, and it etched as well. Slow, 2000 PSI, 25030. Is it just weak concrete?

How new are the houses?

17 years old. This is actually my neighborhood lol. I washed my driveway with the 25025, no etching. It makes no sense. Yet those 2 did

Are you sure it’s etching? Personally, I’d like an -online- education about how to tell if it is etching or just stripes. Anybody got any good links/videos on the subject?

I highly doubt 2000 psi etched 17ish year old concrete… unless those two houses got new driveways around two years ago I just find that hard the believe. Go back and pre-treat it and run the surface cleaner vertical and horizontal in two passes… post-treat if you still see lines.

Do us a favor and get a close up pic of the stripes and in between. I mean like within a foot close.

Tanner, you’re doing so many things wrong. go watch my video. First go perpendicular to line of site. Now that you’ve got your tips right, hopefully around 2500-2700 psi at the gun, go slowly. 95% of my drives I make 2 passes., Sometimes 3 if really dirty. A hw mix is plenty for pre-treatment and 99% of the time good for post-treatment. Make sure you rinse often and rinse enough, you don’t want dirty water to dry. Just like most washing 60%+ of your time will be spent rinsing and use some pressure either with your ball valve or one of your medium high pressure tips Most people don’t charge enough for concrete to do it right, so try to rush thru it. Make sure you really clean it and don’t just rely on chems. Your goal should be that you don’t have to use any post treatment and it still looks good.

PS: In that first pic you posted, if you had gone right direction, that drive would look great.
What part of country you in?


you want to rinse before it dries also. pretreat, let it dwell at least 10min. then surf clean, but rinse within reason. I think I still see green on concrete.

I live in PA. When you say “right direction,” do you mean horizontal? I will definitely watch your video. I’m just scared of going slow and etching something again. I believe that second picture I posted was a clogged tip. That was with 25025 (2600 PSI). The second driveway I did that I believe etched, on this same
street, was with 25030, so probably 2000 PSI. I can’t figure out why that happened. I don’t have a picture of that, but there were similar lines to the
second picture. I ended up going in circles over it. I know for a fact that it was etched because there was gray runoff. However, it doesn’t make sense with such low PSI.

I would have to go back to the home. I know it’s hard to see. I can’t post the full resolution ones. Here’s another one though:
The customer was satisfied thankfully.

That second picture I posted I believe was a clogged tip. Okay, so let’s assume that’s correct. However, that second driveway (on the same street) had the
same problem. Went very slow, post treated 3%. Saw those lines, similar to the second picture. I know it was etching because I saw the gray runoff. This was with 25030 tips, and the first driveway on the street (pictured) was with 25025

Not entirely sure

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