N-Rev Challenger

[DX]

Well, as posted at WWc, I've just finished probably the strangest APH ever built. It looks more like a Star Wars battle cruiser than a water gun! The pc is a weird shape and uses a tee in the base, the pump is elevated instead of down below, the dual reservoirs are along the side facing back, instead of over the back, and the whole gun is unsually compact. I've confirmed that it will work because I got it to dry-fire [with the best homemade pump I've done yet].







Stats will be available after school tomorrow. There are still a few structural things left to do, like wrapping duct tape to keep the dual reservoirs on tight. Except for the pump, this will be very durable when the duct tape is on. The pump looks vulnerable, but it is in the perfect position to switch between it and the ball valve quickly. I can make it more sturdy, if that becomes a problem.

[WaterWolf]

Looks good, um, interesting.
Just a few small problems I can see.

The pump at its current location is weak and bound to snap off, I would suggest finding a way to support it, perhaps by strapping it to the PC.

The positioning of the side reservoirs make it so that you need to tilt the gun upwards when pumping.

(I may be wrong on this one)
I don't see any way for outside air to replace the lost water in the reservoirs. This would result in suction inside the tanks and make it harder to pump.

Other than those small things, it looks good.
I remember toying around with a configuration like this (Sans pump) for a WBL rifle. Can't wait for the stats on this.

[CROC]

I agree with water wolf that the pump is easily snapped off, so shorten the piece of PVC that connects the pump to the rest of the gun, and it will work great!
I look forward to seeing distances
~CROC

[WaterWolf]

Actually, by merely strapping the pump to the PC (With a hose clamp or somthing) you could keep the use of the vertical pice as a handle. (I assume this is your plan for than part)

[Silence]

Once again, unique design, and it could very well form a revolution in homemade-building.

How would you use a hose clamp to hold the pump and PC together, without using actual tubing? You might as well use duct tape or something.

The base of the pump does appear to be a handle, although it looks like the horizontal part might be comfortable too. I don't think changing the length of the vertical part would affect the strength too much.

The reservoir caps allow enough air in. Most people hold water guns at an angle anyway, even during pumping, so the water should get used. I can't say too much for the apparent balance though.

[DX]

I have not taken pictures of the finished product yet. The pump was secured to the pc using a smaller pipe and plain duct tape. The reservoirs were secured using duct tape and stay quite nicely.

The gun is about the length of a CPS 2500, plus a bit more for the nozzle area. The width is not bad considering the design, though it does look unwieldy. It is actually comfortable to hold and you can grip the pc, pump, side, or bottom of the reservoirs, as the weight is near perfectly distributed.

Now for the important stuff, stats:

Range at ~40 degrees:
~48-51 ft [5/32" nozzle]
~45-49 ft [1/4" nozzle]

Full PC Shot Time:
~2 seconds constant, ~6 seconds all

Taps per Tank: Don't know, should be on the low side though

I actually broke it by pushing for too much. The pump is so good that I kept trying to squeeze in more pressure. The front pc to ball valve connection flew off, leaving the open pc steaming like after a Douchenator shot. Normally it should be able to handle the pressure from a mere hand pump, but I guess the glue wasn't dry enough to take it. That would have put the puddle well over 50ft, so now I'm a bit annoyed.

The funny thing is that this pc uses mere 2" pipe and still performs well. You can feel a lack of raw power, but it still consistently puts the puddle at or just short of the 50ft mark with above average stream speed. With a pump this good and a 4" pipe pc, you could really get some range, but it would take a backpack to feed such a thirsty beast.

Even with a few faults, this is still my finest and most practical homemade, primarily for the craftsmanship. The pump does leak a bit at high pressure, but it slides better than any stock pump and holds vastly more pressure than any of my other homemade pumps have. While many have commented on the strange placement of the pump, it is really effective. Switching hands from ball valve to pump and back is just as quick and easy as if it were underneath. I also finally got acceptable range with an APH! That was a huge first, with the exception of my dual chamber APH that I can't shoot because it has no water source.

Now I've got to wait another 24 hours for the fix to dry. My next homemade idea, which needs to wait for more funding, will also feature an "out-of-the-box" style design [and possibly LRT].

[Ben]

Great work.

When you described this before without a picture, I thought it sounded crazy, but from this design I see where you're going. This most definitely will help with balance. I think the problem with other previous designs was that people tried to add a reservoir onto the APH design, which I designed to use a backpack. Simply put, that doesn't work well. I think the basic APH design is great for backpack water guns, but an included reservoir water gun definitely should go for this design.

How much water does the PCs and reservoir hold? Looks to me like you can get many shots from those two tanks.

I'm glad you tried wooden pumps as well. I was really surprised at how well they work. I think Pepper got the entire pump thing right with his first homemade water gun. I guess I just had a hard time believing a wooden pump work work so well!

The funny thing is that this pc uses mere 2" pipe and still performs well. You can feel a lack of raw power, but it still consistently puts the puddle at or just short of the 50ft mark with above average stream speed. With a pump this good and a 4" pipe pc, you could really get some range, but it would take a backpack to feed such a thirsty beast.

I explained this before but I'm not sure if you read it. PC diameter from hand pumped air pressure water guns doesn't matter as much as I may have made it seem. Surely, larger will still be noticeably beneficial, but much less than it is for designs where air is pumped in. The thing comes down to this: what you put is in what you get out. It's the basic conservation of energy principle. Your power on hand pump air pressure water guns is essentially only controlled by how much energy is put into the system. The larger diameter has more volume which means that slightly more energy can be put in by getting closer to the pump's limit. I'm not sure if I explained that as clearly as I could, so if you don't understand let me know.

I would suggest trying some more orifice diameters, trying a conical nozzle, and making the PC use larger diameter pipe. I think you could get 55 feet with these changes. A 4 inch diameter PC certainly will be more powerful than a 3 inch PC. Two 4 inch diameter PCs would be the best for power, but they would take too many pumps. I think two 3 inch PCs are the best combination as far as pumps vs. power goes because they have more area than a single 4 inch chamber. They also are more common and cheaper than 4 inch parts (at least here).

My only other suggestion would be to use cable ties instead of duct tape. Duct tape is cheap and works, but it's messy. Cable ties are stronger and cleaner.

[WaterWolf]

Interesting, perhaps we should consider such a configuration for the "Silver-Bullet" Homemade that we're designing. The PC could fit snugly in the middle spot between the reservoirs Since the Silver-Bullet might be a CPS, that would allow for a very smooth design and good flow.

I'll start drawing up a 3D draft plan for it tomorrow, then people can make suggestions and changes to it.

[DX]

I'm not sure how to measure pc capacity in an APH due to drop-off. Should the measurement be just the shot to a certain point or the entire pc's worth, even though not all that water actually comes out?

I've used wooden pumps from day 1 [hence prior comments about pumps rotting when I left them in and forgot about them]. The weird thing is how I chose wood. When putting together my first APH, I couldn't find aluminum rods, but months earlier, I had found a bag full or wooden dowels in someone's curbside pile for junk day. I thought they might be useful one day and kept them. Therefore, I started with wood and never bothered with anything else. My previous pumps were not notched as well as this newest one is. I spent time on this one to get it perfect, and that effort paid off.

I see what you mean about pc sizes, though my next gun could still use a 3" pc or 3" upper portion [I like using a 2" tee at the bottom, even though I can't prove that it does much for laminar flow]. The problem is that a larger pc needs a larger reservoir, and I hate making homemades heavy and/or bulky. This gun is extremely well-balanced, but the dual 2" reservoirs don't last long. I think I could last 30 minutes or so with this gun in heavy combat, vs 45 minutes with a 21K or a full hour with a 2500. I have a potential design mod for it that gives it 4 reservoir tubes [the same 2 doubled over on themselves]. However, that would require building another gun, which I'll end up doing, but I'm going nowhere without the funds to back it.

I've realized that this homemade really needs better nozzles. I haven't got a conical nozzle, nor know where to find one in a store, though that's the absolute best choice. I stepped down the 3/4" to 1/2", then realized that I haven't got any 1/2" endcaps to drill. There is virtually no stream lamination with the 1/4" 3/4" endcap, hence the worse range. In no way should a 5/32" beat a 1/4" in range, so I know something's up.

Cable ties would be good if I can find them. The problem is that these stores have too much stuff to look at, not to mention that their workers are usually incompetent.

I can get virtually any pvc part, as pressure-rated pipe and fittings for 1/2" to 4" are widely available, with an array of 6" available at larger stores. Whenever I am shopping for homemades, I take time to look for rare pieces. Sometimes they've got huge gold, like 3" - 3/4" reducers, doubly terminated male adaptors, elbows with unlikely angles, etc. These things really change homemade designs and make certain aspects, especially compactness, a whole lot better.

As for the Silver Bullet[s], we should be "creative". My new gun was not only made to experiment with practicality, but also to get people to think. With enough people considering enough radical new designs, the Silver Bullet may come out.

[Silence]

Well then, good luck in battle! The gun doesn't seem so large after all, I just visualized it as 5" wide and it doesn't seem too bulky. Also, are you using cellular core tubing for the reservoir?

The nozzles should definitely help. I know people have used metal pipe nipples as nozzles, and I'd imagine a 3/8" and a 1/4" nipple would be a valuable addition to any nozzle selection, even if you have to use endcaps for the sizes in between.

I haven't found any sweeper nozzles here either, so I might have to go to McMaster-Carr.

[DX]

I wanted to use non-rated cellular core, but Sears didn't sell any smaller than 3". You've got to really search for non pressure-rated pipe here.

The nozzles will make a giant difference. I actually do have a few metal pipe nipples [found them on the curb], but they are all too large for anything other than a riot blast nozzle.

[WaterWolf]

So, what DID happen to the N-Rev Challenger?
I'd agree with Silence, the thing thats will most likely increase your range a fair amount would be to get a 3/16" hose-barb nozzle. I remember that on this gun, that the addition of a hose-barb nozzle gave it a 15-foot increase in range.
That could possibly give the N-Rev Challenger 66 feet of range!
This would most likely make the gun much more battle-practical, with the higher range stats and a better stream.

[Drenchenator]

Nozzles do not just give a straight-out add-on of range. Each nozzle size must be optimized for each setup for range. A hose-barb probably worked well in this setup because it was drilled straight (machined to be precise) and the optimal nozzle size for this gun as well. A good optimal conical nozzle should maximize the range but one nozzle cannot be guaranteed to supply "15 extra feet." The best thing to do would be to try out different nozzles and see which one gets the best range. Each design is different; each has a different optimal nozzle size.