67 replies to this topic

[Vistagecko]

This marks my 100th post and my 1st contribution to this site, yippee. Here we go.
What you're making:


Materials needed:

6 in of 1/2 inch cpvc
1/2 inch cpvc endcap
Dremel or hacksaw
Plumbers goop or hot glue
About 5 minutes

Start by opening up the AT2k air chamber.


Take this black thing and poke a small hole in the exact center.


Replace the black thing and re screw the chamber together.

Cut off the very tip of the goo gauge, and dump the goo.


Now the fun part. Take your 6 in piece of cpvc and twist it on over the goo gauge.


Stick your 1/2 inch cpvc end cap on the top of the 6in piece.


Now take your plumbers goop and seal the cpvc to the air tank.


Make sure your leak free, if you find a leak make sure your goop is on tight.

You're done.
No ranges yet, first shot I got off in my house, went straight through my window. When I can get outside, in daylight, I'll measure how far this monster shoots.

Ouch.

Ranges: before, singled with brass, it got between 75-80 ft. flat.

shot 1: 102'
shot 2: 101'

Average 101.5'. +20', Not bad for 5 min.

Thanks Draconis & Nerfer9 for your help.


Comments, Questions, Flames?

Edited by Vistagecko, 16 November 2008 - 01:04 PM.

[silentsnipe]

I am so doing this...right now.

[nerfer9]

you should of totally of used plumbers goop over the hot glue.

[Vistagecko]

you should of totally of used plumbers goop over the hot glue.

I didn't happen to have any on hand when I did it. If I ever redo it plumbers goop is going on.

[Soothsayer]

Please tell me your weren't aiming any high powered nerf gun at anything made of glass on purpose. right?

[silentsnipe]

I just broke my Atk2. It's not your fault. I just read it too fast.Also, are you saying you broke your window?

Edited by silentsnipe, 11 November 2008 - 11:06 PM.

[boisie]

I have a tiny bit of Maxi-Cure left over if you want to use it. And I'll be buying a new bottle.

By the way, this will be one of the first things I'll be doing to my AT2K with the goo gauge, except with a couple elbows to keep it clean.

Also, the window was probably cause of a crappily made dart. I know how bad he used to make them. They go kinda swooshy and curvey after about twenty feet.

Edited by boisie, 11 November 2008 - 11:09 PM.

[Ubermensch]

I love you. I just got an at2k today and was wondering what to do with it.

[Vistagecko]

@ silentsnipe Would you consider a gaping hole and 6 inch long cracks going outward from the hole, broken?
If so then yes I broke my window. Also never attempt a new mod before first carefully examining the directions.

@ Boisie Yes the dart swayed in mid air. Jacob dart. I'll also gladly take that maxi-cure of of your hands.

@ Ubermensch Your welcome, remember to read the mod carefully before trying it.

Edited by Vistagecko, 11 November 2008 - 11:24 PM.

[TantumBull]

Nice mod. One question, though. What's the purpose of poking a hole in the black thing? Because didn't you attach the CPVC to the other side anyway?

[Banshee]

Does it really increase the range because we've tried goo gauge expansions with failure. Does this actually do anything? Hurry up with ranges. Haha.

[silentsnipe]

[quote name='Banshee' date='Nov 11 2008, 08:59 PM' post='189208']
Does it really increase the range because we've tried goo gauge expansions with failure. Does this actually do anything? Hurry up with ranges. Haha.
Well he said it broke his window, so i'm guessing it didn't fail.

[Draconis]

Instead of hot glue in the end, use a $.25 pipe cap and some adhesive. It will never come loose and be stronger than anything else in the entire AT2K valve/tank system.

[Maeric]

Instead of hot glue in the end, use a $.25 pipe cap and some adhesive. It will never come loose and be stronger than anything else in the entire AT2K valve/tank system.

Exactly.

No hot glue on air systems, it just doesn't hold air. Use Goop. Most people use Plumbers Goop, I use the household stuff. Works fine. Air-tight too.

[Vistagecko]

I got some goop and pipe caps today and I've gotta say it was a lot easier than hot glue.
I'll update the write-up with pictures tonight.

[Ubermensch]

So... before I do this, what is the black thing and why poke a hole in it?

[BendyStraw]

Sounds interesting. Does it take more pumps to fill it up? If that is the case, than it probably gets even better range than before.

[Vistagecko]

You poke the hole in the black thing so the air will flow into the new tank. That black thing holds the goo from getting into the chamber so you will still have a stock air tank even though you cut off the goo gauge. So the black thing is a necessity if you plan on using this new tank.

And yes this increases range greatly. The reason goo gauge extensions don't work very well is because the walls are so thick you're only creating probably a 1/2 centimeter more air tank. With this your creating 6 square inches more air tank. So I'd say its worth doing.

It takes me 7 pumps to pump it all the way up. Just don't plug it. This is an expandable mod, so the longer length of cpvc you use the more psi you can build.

I lost my tape measurer so ranges are delayed yet another day. For now I can give you a rough estimate. It outranged my singled big blast by about 40 ft flat.

Edited by Vistagecko, 12 November 2008 - 04:41 PM.

[Ubermensch]

Does re size of the hole you poke in the black thing matter?

[Vistagecko]

Does re size of the hole you poke in the black thing matter?

Not from what I can tell. I did this mod again to my other AT2K and i just poked it with a small screwdriver each time. And you have to replace the black thing. If you don't for some reason it leaks air.

[clutchjunkie]

So... before I do this, what is the black thing and why poke a hole in it?

The black thing is a rubber diaphragm inside the "liquitron power chamber". You poke a hole in it so air will go through it and into the cpvc tube.

Just so you guys know, you can get the same effect by removing the goo guage completely and replacing all the tubing in the blaster with 1" of 5/16 i.d. tubing. It will take a few extra pumps to pressurize everything and you get a more reliable setup if you goop everything properly.

[imaseoulman]

I have to admit I'm pretty dubious. I see flow rate being a majorly restricting issue. The ID of the passage from the goo tube to the AT2K can't be more than 1/8" (okay, maybe like 5/32, but that's pushing it). That kind of restriction is normally prohibitive to increased performance, but maybe I'm missing something.



On a side note, there is a lot misinformation being bandied about here. Just a few quick things to make sure we're understanding what's actually happening.

1.) You are not increasing by six square inches. Volume is measured in cubic inches, so is that six cubic inches? That's not a small amount. If I recall correctly, the AT2K chamber is only about 1.75 cubic inches (radius of 3/4" and height of 1"). So 6 cubic inches would be the size of about three and half AT2K tanks. It also says that you're only getting seven pumps worth of air in there. You can get about that much air in to a pump-plugged AT2K without expansion. (Okay, I just went back and checked and it said the expansion is 6" of CPVC, that's rought 1.75 cubic inches).

2.) Lengthening the CPVC does not increase PSI ( Pounds Per Sqaure Inch). The pressure is the same, but more CPVC does increase the volume or amount of air in the system. If flow rate is adequate and PSI is constant, an increase in volume will produce a greater range, but the amount of air that can flow out with a stock AT2K valve quicly reaches a critical level where adding more air volume does nothing.

I'm not trying to be a jerk about any of this, I'm just trying to keep us on the straight and narrow.

[Vistagecko]

I have to admit I'm pretty dubious. I see flow rate being a majorly restricting issue. The ID of the passage from the goo tube to the AT2K can't be more than 1/8" (okay, maybe like 5/32, but that's pushing it). That kind of restriction is normally prohibitive to increased performance, but maybe I'm missing something.



On a side note, there is a lot misinformation being bandied about here. Just a few quick things to make sure we're understanding what's actually happening.

1.) You are not increasing by six square inches. Volume is measured in cubic inches, so is that six cubic inches? That's not a small amount. If I recall correctly, the AT2K chamber is only about 1.75 cubic inches (radius of 3/4" and height of 1"). So 6 cubic inches would be the size of about three and half AT2K tanks. It also says that you're only getting seven pumps worth of air in there. You can get about that much air in to a pump-plugged AT2K without expansion. (Okay, I just went back and checked and it said the expansion is 6" of CPVC, that's rought 1.75 cubic inches).

2.) Lengthening the CPVC does not increase PSI ( Pounds Per Sqaure Inch). The pressure is the same, but more CPVC does increase the volume or amount of air in the system. If flow rate is adequate and PSI is constant, an increase in volume will produce a greater range, but the amount of air that can flow out with a stock AT2K valve quicly reaches a critical level where adding more air volume does nothing.

I'm not trying to be a jerk about any of this, I'm just trying to keep us on the straight and narrow.

No, I appreciate the criticism. If you feel I have said or explained something incorrectly please let me know.

I want the write up to be clear, to the point, and simple.

Imaseoulman thank you for more indepthly explaining how the tank works. I'm sorry if I misused any terms or didn't explain something clear enough.

Edited by Vistagecko, 12 November 2008 - 06:33 PM.

[Galaxy613]

Nice mod. One question, though. What's the purpose of poking a hole in the black thing?

I thought the same thing, but the edge if the black thing seals the chamber, it will leak air without the black thing or using some goop or hotglue to fill the gap the black thing used to connect.

[imaseoulman]

I have to admit I'm pretty dubious. I see flow rate being a majorly restricting issue. The ID of the passage from the goo tube to the AT2K can't be more than 1/8" (okay, maybe like 5/32, but that's pushing it). That kind of restriction is normally prohibitive to increased performance, but maybe I'm missing something.

I don't think you are missing anything at all. It takes longer and/or tighter barrels to take any advantage of the "late" air. The discharge is sort of a "pop-whoosh" though I am not claiming to be able to hear the difference.

And, I just took a micrometer to the ID of the red flange at the blast chamber, and got 0.09" as a max, so it's even smaller than your guess. This is clearly not the best way or place to extend the chamber, but it is probably the easiest.

You make a good point with it being the easiest tank expansion, but even still, I'm not sure it's really worth it. It wouldn't be a bad way to attach an air stock, but not my preference for an expansion.

For tank expansions, I usually use a PVC Tee and have the barrel protrude right out of the tank. You can buy tees that have half of the straight part missing, I'm not sure what these are called, but my home depot stocks them. Next time I'm there I'll look and see what they're actually called. I've also got an AT3K with this type of expansion done to it, I just need to post a write up for it (and about a million other things).