Thank you @sk1 !
Well, I have been busy the last couple of days, although a lot of it has not necessarily been what you would call progress. Killing two timers, and returning two tanks isnt much fun.
But the new Hypro nozzles came yesterday, and I got them hooked up and did some preliminary testing. This is without timers and no tank, so things will change once the system is complete - I hope for the better.
Part of the āno progressā thing is that these new nozzles DRIP! Possibly even more than the tefens. They do make slightly better looking mist, and they do have a higher opening and closing pressure - both good things. Plus, they have far less ālagā than the tefens did. More on that later.
This is frustrating because Atomizer tells me his Hypro nozzles do not drip, and they dont open until the pressure reaches 58 PSI. Mine open, and start dripping at 30-35 PSI. I dont know if its a quality control thing or they changed the specs or what, but its irritating as heck.
Its not necessarily a deal breaker, but the drips will put a dent in my D2W plans. I wont know how bad until I can run some flow tests with the entire system in place. I wont have the new timer or tank until Thursday it looks like.
Anyway, I hooked up one of the hyproās and ran it by switching the solenoids on/off by hand. Here is a video of that first test. You can see the unwanted drips shooting out at the beginning and end of most of the cycles.
Looking at the video one frame at a time, it looked like the time from the first appearance of any water until the spray was fully āonā was roughly .1 seconds on average.
The shortest time was .07 seconds and the longest was .17, but most were right at .1.
The time for the water to go from full on to full off was longer. The shortest time was .07, and the longest was .2, but two others were .17.
Those times are rough. It was hard to judge exactly when the spray was fully on or just starting to diminish in the small preview window in the editing software. I decided to rig up an LED to turn on/off with the solenoid to get a better idea of the lag times, so I salvaged an LED light panel from an old DIY underwater camera setup.
This is the second test with the LED light.
Looking at this one frame at a time, the mist becomes visible in the same frame that the light turns on up to at most .03 seconds later.
Each frame takes up .03 seconds. That means the nozzles starts emitting spray some where around .03 seconds, or less, after the solenoid turns on. Then, the spray reaches full output after a total of .1 seconds on average.
It takes a lot longer to turn off, but it doesnt seem excessive to me. The average is .17 seconds with a single outlier at .2 seconds - exactly 1 frame extra. So it takes roughly twice as long to turn off as to turn on. Total lag time is around .3 seconds Ā± .03 to maybe .06 seconds.
I have no real clue, but that doesnt seem all that bad to me. At least I hope its not bad 
I think I can get down to a little under 1 second pulses and still have a reasonably good spray quality - I hope.
The key question is how much water am I wasting during that .3 seconds plus the drips? I wont know that until the timer, and tank gets here and I can run some output tests - shooting into a plastic bag.
Well, that assumes my luck changes and the parts arrive on time and in good shape!
One other thing that I was very relieved to notice is that there are fewer drips in the second test than when I did the first test. The only reason I can think of for that, is maybe trapped air - which might add to the lag - is getting purged? No matter why, Im glad to see that. There are still drips, but not as many.
lurking here and loving every step.
