WaterWar.net

After reading many scientific papers on the subject, I'm convinced that endcap nozzles aren't as bad as some folks believe, or at least can be made decent. Given this, I plan to do some experiments with endcap nozzles. I am developing an experimental setup that will be designed to eliminate hard to control factors like wind and how quickly you open valve as well tell you the spread of the water via the "bucket test" I mentioned previously. I'll detail this later after I've done some math to test the feasibility of certain ideas.

So, what do you think I should test? I made a short list, which is reasonably comprehensive, but I want to make sure I'm not missing anything:

• hand drill vs. drill press (I might skip this because I think it's safe to assume that hand drills are bad, but it'd be interesting to know how bad they are.)
• removing lip vs. not removing lip
• drill speed (both rpm and how quickly the bit is pushed in)
• center vs. off-center
• curved vs. flat cap
• pre-drill (with small bit) vs. not (only for larger nozzles)
• # of passes with the drill bit (probably not important)
• effect of different materials (You can get caps in materials other than PVC. I don't expect this effect to be large but I am curious.)
• effect of laminators (including testing the effect of length, and possibly diameter of the straw)

Let me know if you can think of anything else. These tests will be probably fairly time consuming, but I'll use a fractional factorial experimental design to reduce the time as much as possible.

(In terms of the best nozzles we could make, I think a CNC lathed nozzle like what you might get from this service would be best, but I'm not convinced that the improvement from using a custom made CNC lathed nozzle is more than 10% or so in range given our current knowledge of nozzle physics. I think we'd need a new technology to get more of a range increase from the nozzle alone.)

Did this thread fly under the radar or is no one interested in making better endcap nozzles?

Since I lack a drill press, and every hand drilled nozzle I've done has been messy (although of varying quality; the ones made with the corded drill are usually better), I've stuck to other solutions. My latest is detailed in this thread:

http://www.waterwar.net/site_wwn/board/topic6529.html

The washer is damn near perfectly machined, and results in a quality stream on the 2500. I haven't tried it on an endcap though. Also, the imperfect connection with the larger nozzle may cause turbulence, but it doesn't seem to be too bad.

Nice find CA99. Seems that I missed that thread.

McMaster-Carr suggests that part is called a nylon countersunk washer. The part number there is 90262A029. That definitely is something worth testing.

Yeah, that sounds like the right word for it lol.

I got 12 of these the other day of assorted sizes up to 1/4" on the inner hole. They seem difficult to find and just happen to be at my local ACE hardware, but can't find them anywhere else. (That said, there are extension springs very close to Max-D size that I found at a hardware store near Scott's.)

I could sure use some information on nozzles endcaps. All the nozzles I have ever made, I have made without any proper tools or workplace and the resulting streams have been... disappointing.

soakinader wrote:I could sure use some information on nozzles endcaps. All the nozzles I have ever made, I have made without any proper tools or workplace and the resulting streams have been... disappointing.

How have they been disappointing and specifically how do you make your nozzles?

My first experiment was using bottle caps. I tried making various shapes (slots, semi-circles, etc) to see if the stream produced would be interesting or useful. They weren't.
Later I tried making several sizes of holes for testing purposes. I would make an indent by turning my knife into the plastic and turning it. Afterwords I would take several drill bits and twist them through with my hands in order to make the holes. The result was quite poor.

My garage is still in a state of chaos but I FOUND THE DRILL PRESS, and if I can get that working and/or find the drill charger... I'll be back in business!

Long story short, plastic bottle caps are easy to cut, easy to twist on/off, and they are dirt cheap, but they are.. lacking certain qualities for a water gun nozzle.

I'm interested in flat vs curved nozzle endcaps, but more specifically than just curved- more like conical. After water escapes from the valve, it needs a small section for the water to... "laminate" followed by an exit hole that directs the flow with minimal disruption. I think there is more to it than just the hole itself.