Ike's Prototype Project - My first laminar nozzle

Here is the first working prototype of my laminar nozzle.

Since I live in an apartment and don't have a workshop of my own yet the whole thing was constructed using nothing but a hack saw and a cordless drill. So it's a little rough but I'm pretty happy with how it turned out.

The nozzle is made from 8" PVC and has a tangential inlet on the bottom that I cut with a hole saw. The two end plates are made from 1/4" plexiglass and sealed using threaded rods and #8 screws. I bought a sheet of neoprene rubber off eBay that I cut into squares and used as gaskets between the plexiglass and PVC. That helped to make up for the uneven cuts left on top of the PVC by the hacksaw. The brass nozzle I purchased from John (works great! thanks!) and secured in the plexiglass hole I cut using loctite epoxy. I'm pretty impressed at how well it holds actually.

Here are a few pictures of the result with the pump at a little less then half output:


My nozzle and the great PVC primer smears lol


View of the top plate plexiglass, gasket, and the brass nozzle.


My arch! I was very pleasantly surprised that this was the result of my first test. I expected water explosions and chaos. It doesn't look to bad, a bit jittery though. Low-pass filter is next up on my build list.


Back view of the laminar arch.


And the required hand behind laminar stream shot. The refraction of my hand in the stream is pretty cool looking!


I tried the nozzle again later tonight with the pump at full output and got an arch about 7' x 13' ! The problem was that it started breaking up about 4' from the end. I think this was mostly due to the pump jitter which I am hoping a low pass filter should fix. We'll have to see. My other thought is that I have some doubts about how perfectly square the brass ring is seated in the plexiglass. I got so worried about the epoxy when I put it in that I forgot to square it. I might get a 3/8" Lexan plate so I can bore out a 1" hole with a Faucner bit partially through plate like mario has. The brass ring will sit in it and guarantee it sits square with no burs.

Here's my to do list:
1) Build a Low-pass filter
2) Possibly replace top plexiglass plate with 3/8" Lexan. (The plexiglass bends a bit from the pressure on the threaded rods)
3) Get it working at full pump output
4) Add fiber optics (LEDs are in the mail!)
5) Add cutter
6) Build a ethernet control board (I'm an Electrical Engineer so this is the part I'm better at)

Thanks to everyone on this board for the inspiration and great advice! I'm having a blast and don't plan to quit anytime soon. I'll post some more pictures once I get a filter put in place.

Hello Ike

That is impressive !!
What a nice and clean build nozzle.

And the water is perfect, you say you need a low-pass filter!
Are you sure you need one?
If the pump is high quality, a low-pass is maybe not needed. (I dont have)

It was not so easy to see on the picture, but it seems like the straws was pretty close to the output hole?


Anyway, I loooove that nozzle when is the cutter in progress ?

Thanks liteglow Now that I have a working nozzle I'm just that much more excited about it all.

The reason I want a low pass filter is for when I turn the pump output higher. I don't have a picture yet but when I turned the pump up to maximum the arch got quite a bit bigger which is what I want, but it also caused the stream to start to break up a few feet before it got to the tank. If I watch the stream closely at the nozzle I can see small little jitters in the pressure. I'm hoping that this is what is causing the issue and removing the jitters with a filter will let the stream stay laminar all the way to the end.

The straws are 2 inches (~5cm) from the output. What do you and others have for space between the straws and the output? Does more or less space seem to help?

As for the cutter, that should come as soon as I get the lights installed. I have about 5 different designs laid out on paper that I want to try. One of them is for a stepper motor/solenoid hybrid mechanism involving an angled cutter plate. I'm curious to see how it will do.

So much I want to try out and so little time at night to work on it! I need to win the lottery so I can quit my job and just work on my fountain all day

Fantastic Nozzle - I had a plexiglass top crack while being used.
I switched to 3/8 PVC sheets - works great here's the link.

http://freckleface.com/shopsite_sc/store/html/pvcsheet.html

After playing with my nozzle this weekend I think I found why the stream starts breaking apart at the end when I have the pump on full!

Some of the straws have air bubbles trapped in the end of them while it is running which means they aren't getting any flow through them. This probably indicates that my filter pad is not thick or dense enough to equalize the pressure before the water enters the straws. (I have a fairly thin and course filter pad)

I see from looking at some pictures here on the forums that many of you have nice dense looking filters. What kind of filter do you guys use and where did you buy it?

Try using upholstery foam. Its fairly cheap compared with the type used in pool filters. I bought a some 2' square 1inch and 2inches thick for about £5.00. It seems to work OK

I've also played around with weed barrier. It's supposed to allow the water to pass through it but block the weeds.

Found a great site for filter foam!

http://www.swisstropicals.com/Poret%20Filter%20Foam.html

I have a 30 PPI 2" thick pad ordered. Looks like great stuff for a nozzle and should be solid enough I can rest my straws directly on it with no need for window screen between.

I've been looking for a site like that forever! Thanks Ike!

Here's what I use - found it at Home Depot - works great - one is fine one is course.

http://www.homedepot.com/h_d1/N-5yc1vZ1xmi/R-202017146/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053