30 replies to this topic

[Azrael0987]

This will by my submission for mod contest. This is simple and cheap to make, so it will be in the snap category.

My first homemade was another air cannon, very simple in design, and again very war worthy (ask ShaNayNay or HeWhoMods). In my design I use a very high volume pump, which equates to 2 to 4 pumps between shots. But originally I used a large bike pump, which are somewhat expensive. In this write-up i'm going to make a fully pvc version that still has the same great performance, for 25$.
This is my first design, and it works amazingly. Its been through two wars without any problems. It is easily hopperable, and even feeds elites through a wye reliably (as does all of my homemade blasters actually. maybe my wye is magic).

Materials:
1 1/4 inch pvc
1 inch pvc
3/4 inch pvc
1/2 inch ball valve
1 1/4 inch coupler (times 3)
bushings down to 1/2 inch (I had to stair step down, but if you can find a bushing straight from 1 1/4 to 1/2 it'd be easier)
1 1/4 by 1/2 inch threaded bushing (times 2)
1/2 inch threaded elbow
1/2 inch threaded tee
1/2 inch thread nipple
1/2 to 3/4 threaded adapter (times 4)
1 inch plug
O-rings
PVC glue
marble (times 2)
small diameter nail (times 2)


: 1/2 inch ball valve

: 1 1/4 inch coupler (times 3)

: 1 inch by 1/2 inch bushing

: 1 1/4 inch by 1 inch bushing

: 1 1/4 inch by 1/2 inch threaded bushing (times two)

: 1/2 inch threaded elbow

: 1/2 inch threaded tee (threaded on all three sides)

: 1/2 inch thread nipple

: 1/2 inch by 3/4 inch threaded adapter (only 1/2 side is threaded, times four)

: 1 inch plug

I know that was a ton of pictures and anyone with a slow connection hates me, but when I was first getting into modding all the parts without an explanation of what they were was confusing. And its easier to explain what I bought with a picture than words.

Tools:
hammer (in case the pieces don't want to connect well)
table saw/bench saw (the only hard part to the entire project, but you could get by with a file and a LOT of patience)
some way to cut the pipe
drill/ drill press


Assembly:

Front tank section- The ball valve, 1 inch by half inch bushing, 1 1/4 inch by 1 inch bushing, and one of the 1 1/4 inch bushings need to be glued together.

Rear of tank- a 1 1/4 inch coupler, 1 1/4 inch by half inch threaded bushing, and 1/2 inch threaded elbow need to be glued together.

Rear of pump- a 1 1/4 inch coupler, 1 1/4 inch by 1/2 inch threaded bushing, 1/2 inch thread nipple, and 1/2 inch threaded tee need to be glued together.

Here is an exploded view of what I just said, minus the front tank section (I don't think that one is hard to follow)

Now the front and rear tank sections have to be connected with a length of 1 1/4 inch pvc. And a length of pvc attached to the rear of pump assembly.
The lengths can be adjusted to help suit your body (you don't want the pump extension so long you cant reach it). I personally used 15 inches for the tank and 18 for the pump (I'm 6 foot).

Edited by Aeromech, 23 November 2015 - 03:06 AM.

[Azrael0987]

Check valve-

I substituted the 3/4 inch male pvc slip adapter with a 1/2 inch to 3/4 inch threaded adapter because it has a larger lip for the o-ring and ball to sit on.
Once the check valves are complete you can screw your tank to the pump tube, and the second check valve (preventing a vacuum in the pump) onto the back of the tee.

[Azrael0987]

Pump-

You only need to make the "piston" for this application.
Once your pump is finished you can lube it up and insert it into the pump tube.




Feel free to ask any questions and I will try my best to answer them efficiently.

[Ivan S]

How heavily does performance rely on turning the valve quickly? Is there a trade-off between turning the valve quickly and accuracy?

[Azrael0987]

The faster you turn the valve the better the shot. If it gets opened slowly it can misfire. It takes a little getting used to, but id feel comfortable loaning it out.

[Ivan S]

The faster you turn the valve the better the shot. If it gets opened slowly it can misfire. It takes a little getting used to, but id feel comfortable loaning it out.

But would you say that when turning the valve for competitive power, you can place the shot as accurately as a springer? Sorry for my skepticism, but in my experience with ball valve triggers, turning them fast enough for a good shot always results in too much shake for acceptable accuracy.

[BuffNerd]

I know that at a lot of wars homemade air guns are banned due to how overpowered and dangerous they can get, but what are the ranges of this one?

[ShaNayNay]

I know that at a lot of wars homemade air guns are banned due to how overpowered and dangerous they can get, but what are the ranges of this one?

This thing outranged my 4B with stock pump, but during that match azrael was using double weighted slugs too, so it's difficult to say how overpowered the blaster itself is.

This blaster works for wars where rules are moderately lax, as it stands alone as a usable blaster, and isn't so overpowered that it is cheap or dangerous to use.

Since there is no OPRV, it still can be pumped up to ridiculous pressure, so obviously most wars that ban air cannons won't allow it.

[Azrael0987]

The new design doesn't allow it to get as highly pressured. After a certain pressure is reached the pump cannot open the check valve to the tank and forces the air out around the pump. I play for fun, and make sure to not over pump it. I'm not there to hurt anyone. When I was say 100 feet out I would pump it more(causing me to out range you shanaynay). Id pump it less when I was closer to avoid pain. Even with the shaking I am able to shoot accurately. Its actually very easy to use once you're used to the way it works. It is different than a springer in play type, but still works very effectively.

[DartSlinger]

Using a ball valve is probably the most common trigger mechanism that air gun beginners use, but they're just plain terrible. The air release is slow, shaky, and requires two hands. You've apparently gotten used to these characteristics by now but, you could easily make a much better trigger by putting a homemade check valve in between your tank and barrel and having your trigger be a cut off nail, screw, or something similar that presses on the ball in the check valve. In essence doing what 3DBBQ does in all of his homemades, an example being his Mad Ghost. He always uses a PVC check valve, but those are much more expensive than making a check valve.

[Azrael0987]

That is a very good idea and a place for further improvement. Also working a way to put the anti vacuum check valve built into the pump head. Ill start working on the check valve trigger soon, since I have until June. But honestly after say a half an hour of playing around with it a ball valve is very easy to operate and use effectively. I know its not preferable, but for a first homemade, it works very well and is very reliable. When I made my first one it took me a little while to get used to but now I can do it without any thought required and shoot without bad openings.

[Langley]

This is really simple and easy to build, and the quality of the writeup is good, but I have never attended a nerf war where this thing would ever have been allowed. I think the same goes for pretty much anyone judging this contest. Sorry, but this just isn't what we're looking for.

[Demon Lord]

With the addition of an over-pressure-relief valve on the tank, it might be eligible to use at some wars; without on however no one in their right mind would allow its use due to the danger factor it currently has.

[Azrael0987]

Again, this one wont reach pressures nearly as high as the other one, and is NOT any more dangerous than a pump snap. The pump doesn't have a 100% seal like Grant Thompson's does, and once a certain pressure is reached in the tank, the pump wont force open the valve. Maybe if it did have that amazing seal it could squeeze a few more pumps in there, but even then there is a limit. Eventually the pump cant open the valve.

[He Who Mods]

This thing outranged my 4B with stock pump, but during that match azrael was using double weighted slugs too, so it's difficult to say how overpowered the blaster itself is.

His air cannon rocks. This new writeup is great for people who do not want to buy a pump.

This is really simple and easy to build, and the quality of the writeup is good, but I have never attended a nerf war where this thing would ever have been allowed.

We let him use it at our Missouri wars with a certain number of pumps, it isn't too bad, shoots only a few feet further than my pumpsnap, it does not hurt any more than the other primaries. It just needs an adjustable OPRV to be perfect.

Edited by He Who Mods, 17 September 2013 - 04:49 PM.

[Parallax]

So it's a pump, a PVC air tank (yeah, that's a brilliant idea), a ball valve for a "trigger", and a coupler for a barrel assembly.

Uncomfortable, unsafe, ugly, expensive, and unoriginal.


And honestly, I'm all for people building things, putting plans into action, making write-ups, etc. but when someone comes out with something blatantly dangerous and then advocates other people do what they've done then I think that's when the community needs to come down hard on them.

I know the two common counter points to this too. First, you're going to say that with proper construction you will probably be pretty safe using this thing. This is most likely true if you're a decent builder, but you have to realize that you're putting this on a forum where hot glue, duct tape, and nails abound as construction materials. Some little kid somewhere is going to look at this write-up, get the brilliant idea to make one of these with a bunch of unrated PVC he found in his backyard, not use proper solvent welds and then pump it up too high and blow his fucking face off. This is not the kid of design that Nerfhaven needs to proliferate on the internet.

Second, you're going to say that the likelihood of one these blowing is pretty small, lots of people make similar things and you never hear about anyone dying. Well, similar to the above scenario there are just too many factors that could cause the PVC to weaken and eventually fail. Sunlight (UV rays) cause PVC to degrade, temperature fluctuations makes PVC brittle, shock (running, pumping, dropping) increases the chance of the PVC failing drastically more so than in intended applications. If you look at the typical war all of these factors are hugely present: it's usually outside in the summer or winter with lots of running and jumping around. So not only is this thing unsafe out of the box, it's only going to become more and more dangerous the more you use it.

If this was the platform of a water gun, instead, it'd be a great design but you're using the wrong materials for the application and the design really isn't innovative at all to begin with.

Try again.

Edited by Parallax, 19 September 2013 - 04:19 PM.

[Azrael0987]

I'm not in any way saying you are wrong. You do have good points. I'm just putting my defense in. Uncomfortable, no not really. Its not bad to shoulder actually (despite how the back of it looks. ). Unsafe, if you're a nimrod. PVC is way more durable than most people think. I know PVC's limits, as I use it very regularly for other applications other than nerf. I specifically said a safe pump amount, and I would highly suggest not going over that number. Someone could use it wrong, you are right, but someone could point a plus bow at their eye too. Everything has its own risks. Many of those have a major variable placed on the comprehension of other people. I never said it was perfect. Ugly, yeah so are 95% of all homemades. Expensive, actually its pretty cheap (especially compared to a plus bow). And yeah I know its unoriginal. But its my take on a homemade air gun and I thought id share it. I don't think you need to be a great builder for this. It is literally gluing things together. Its one of the simplest things I have ever built.

EDIT: Please note, I didn't make any comment about the likelihood of it blowing up. But yes, you are right, it is a very small chance. Thank you for pointing that out.

Edited by Azrael0987, 19 September 2013 - 07:33 PM.

[He Who Mods]

If this blaster was unsafe, we wouldn't let him use it in our wars. The pressures in the tank are no higher than the pressure of a 4B, also, the check valve he made cracks after a few pumps, since it cannot contain high pressures, acting as a sort of OPRV. The chances of the blaster exploding are extremely, if not completely low due to the fact that it is not even possible to put enough pressure in the tank with pump and set up shown. Also, while this may be an old design, many new factors are involved such as the homemade pump and check valves, and the design is much more streamlined and safe then the usual ball-valve cannon. Again, this cannon shoots even with a snapbow not at all being a "cheap blaster", and isn't the extremely unsafe cannon it seems to be.

[KoRnEd]

So most of the usual air-powered pvc blaster discussion has been said, and again it must repeated for those who time and time again throw safety into the wind and disregard the advice of seasoned veterans.

PVC IS NOT RATED FOR AIR PRESSURE
You've heard this a million and one times before, so why would it be irrelevant?
If you observe how many "home-made pvc tank blasters" are made, you will inevitably run into someone with a horror story. And guess who has one? Yours truly. I was once dumb enough to build one of these, even so far to use a "safe" design (such as yours). I was saved by either a miracle or just lucky coincidence. I pumped one of these 7 times with a ball pump. 7 times. Accidentally dropped it. On carpet. And it exploded. No, not where I solvent welded it, the whole thing shattered right in the middle. It wasn't major at all, since it was a three foot drop. The shattered pieces flew up and hit my glasses, which saved my eyes from diddle.

It was enough to turn me off from airguns once and for all (heck, I'm even scared of springers that use pvc)

Moral of the story: These designs are worthless to post because not only has it been done more times than years you've been nerfing, but the safety makes it not war worthy (contrary to your title). We wouldn't war with one of these on the field ever. And we're from socal.

I would say "try again", but I highly doubt you'll come up with anything better.

Edit: The "safe" blaster I used had an OPRV. They wont save you. A "safe" design would be something like Kane's or Mysterio's.
Edit #2 addressing "He who mods": "homemade pump", "check valve". I fail to see how these are new concepts, let alone more "Streamlined" or "Safe". I'd argue that manufactured pumps are safer AND more streamlined as they are designed with pressures in mind, and also DESIGNED.

Edited by KoRnEd, 20 September 2013 - 06:27 PM.

[Azrael0987]

There is a psi rating on the side of the pipe.

Edited by Azrael0987, 26 October 2013 - 01:12 AM.

[Carbon]

seriously do you guys even read the words on pvc pipe?

Protip: don't have attitude when you don't know what you're talking about.

The 370 PSI rating is for water only. Water doesn't store energy under pressure, and a PVC pipe that fails under water pressure will just break/crack. Air, on the other hand, stores energy when compressed. A PVC pipe that fails under air pressure explodes into shards, and will basically ruin your day.

Now that the important safety message is over with: shut the fuck up. You've shown yourself to be an idiot twice already. Don't go for three.

[Asamere]

While all this is all well and good in terms of concern, I feel this is taking away from what the point of this post was. Sure the blaster has it's bad points. "Dangerous the Blaster may be" and yes, in the terms of "common sense" as our trust, no it isn't the best idea around. Its not idiot proof, no.

An over pressure valve, OK, sure that a good tip and fairly easy, a small drill hole and some epoxy and it fits right into place. Provide a link or something like one such as http://www.mcmaster....119/487/=omkoy3 .

The idea is to create a blaster and make it safe and fun for everyone. Not destroy the fun of creation. I personally love air blasters. I understand their are many implications and by no means is it OK to hand someone a blaster of any type and expect them to know it like the one who built it. Nor is it OK to just take someone's word for making something. This is where the judgment of officials steps, deciding if the blaster is war legal or not.

I think it's a good start for a blaster that isn't fully finished yet. I also appreciate the advice of the vets who have done it all before. So we add 10 dollars and made this blaster a bit safer. Even with this installed, it's still up to the discretion of the judges who govern a war if you can use it or not. Just advise caution when building these, and ask people to add safety into them...

Keep delving around, keep making news models... Never stop trying to get range/safety/RoF all in balance. That's what I've re-learned from this posting...

[Azrael0987]

While all this is all well and good in terms of concern, I feel this is taking away from what the point of this post was. Sure the blaster has it's bad points. "Dangerous the Blaster may be" and yes, in the terms of "common sense" as our trust, no it isn't the best idea around. Its not idiot proof, no.

An over pressure valve, OK, sure that a good tip and fairly easy, a small drill hole and some epoxy and it fits right into place. Provide a link or something like one such as http://www.mcmaster....119/487/=omkoy3 .

The idea is to create a blaster and make it safe and fun for everyone. Not destroy the fun of creation. I personally love air blasters. I understand their are many implications and by no means is it OK to hand someone a blaster of any type and expect them to know it like the one who built it. Nor is it OK to just take someone's word for making something. This is where the judgment of officials steps, deciding if the blaster is war legal or not.

I think it's a good start for a blaster that isn't fully finished yet. I also appreciate the advice of the vets who have done it all before. So we add 10 dollars and made this blaster a bit safer. Even with this installed, it's still up to the discretion of the judges who govern a war if you can use it or not. Just advise caution when building these, and ask people to add safety into them...

Keep delving around, keep making news models... Never stop trying to get range/safety/RoF all in balance. That's what I've re-learned from this posting...

Thankyou. I like and appreciate your approach better than purely unconstructive bs.

[Meaker VI]

Captain Slug used to use paint ball pressure tanks or emptied propane tanks (careful doing that!); both of which are air-pressure rated, and should be good for pressures way above anything we need. Doom's done some experimenting with cheaply built air bladders, and they fail by splitting rather than exploding and sending shards of PVC everywhere. You should be good if you replace your PVC air tank with one of those options and use pressure-rated fittings in between it and your barrel.

[Langley]

Captain Slug used to use paint ball pressure tanks or emptied propane tanks (careful doing that!); both of which are air-pressure rated, and should be good for pressures way above anything we need. Doom's done some experimenting with cheaply built air bladders, and they fail by splitting rather than exploding and sending shards of PVC everywhere. You should be good if you replace your PVC air tank with one of those options and use pressure-rated fittings in between it and your barrel.

As I said before, this is an interesting write-up, but since it would be banned from pretty much all of the wars I've attended, I can't really accept it as a valid entry in the contest. You should take a look at Meaker's advice above and consider building a really idiot proof fail-safe into your design. If you could come up with a simple design that incorporates a pressure tank that fails safely long before any of the PVC parts would crack, that would push air-gun homemades forward quite a bit, and get you back into the contest.