No matter what I do, I still get faint stripes on aggregate and brushed concrete. 4/4 machine, Ultra Clean 16", 2502 and 25025 tips, pre and post treat. I had to go over each section again vertically to fade them some. Trust me, I don’t outrun the cleaner, fairly slow and methodical.
I have three GP Hammer Head surface cleaners all on identical pressure washers. The oldest cleaner started to leave stripes about two years ago. Changing the tips, adjusting the swivel and replacing the skirt helped some but did not fix the problem completely. Even with pre/post treating, you would always have to walk slower than the other machines and go over areas twice. I replaced the bar underneath it a month ago and now it’s like new. The nozzles on the bar sit at the perfect angle to apply enough down force to clean while spinning. If the nozzles or angels are off a fraction, It will cause the cleaner to leave stripes. I had to stop one of my guys from running off the corners of sidewalks. He was letting the nozzles nick the concrete.
I found a technique on a forum a long time ago to prevent stripes 100% of the time because like you I had to go over it twice.
Push the surface cleaner forward an arms lenght, move to the left 6 inches or so, pull back, move to left 6 inches, push forward and so on till you make your way across the driveway. Move up to the dirty spot and repeat back. You can push forward and back realtively fast. The surface cleaner seams to clean the best on the edges. You’ll see every 6 inches it gets cleaner and by the time the surface completely passes where you started it will be clean. No need to go back at another angle. Best part is you can push and pull pretty fast. I found it takes the same amount of time as walking slow up and back.
Just went to change out my tips from #5s to #2s for the rented hot water unit I’m using on Monday. I hadn’t noticed any stripes but I had noticed some shimmy. Bet this thing will work a lot better without a chunk of metal in in one side! The filter exploded internally and got into the tips. Now I have to find a Hp filter before Monday…
I need to make one because it sucks trying to explain it. It takes me about the same amount of time and I don’t have to go back over perpendicular to the path I just walked to get rid of the stripes. It is the only way I will allow my employee to clean concrete because doing it twice is a waste of time.
I use a 4 gpm, 4k psi machine. If you are using a 8 gpm with 4 nozzles I don’t think you have this problem.
Try this method for a driveway and see how long it takes you. You will get zero stripes and moving the surface cleaner back and forth faster makes me feel like I am moving faster. Pluse you only have to go over it once. I hate surface cleaning because it’s boring and I can’t standing walking so slow. It drives me nuts.
Sure, nozzles will get clogged without a filter. But not often. If it happens clean the nozzle. Runs better without the restriction. No need for one on turbo either, but about half of mine have them. If they come with them when I order them they stay on, if they don’t, I don’t add one.