294 replies to this topic

[Vintage]

In garden hose sections of home and garden stores, you can buy special valves that shut off the water supply in a hose. It's another valve that has a possible use here.

I just don't like twisting something to open up the airflow. I like push or pull valves. Until I find one, though, I think I will try the crimping idea. Here is the type of valve I would dig for this job.

~Vintage

Edited by Vintage, 28 August 2004 - 08:03 PM.

[texmustache]

I'm sure i mentioned numerous times that the valve release air after being pressed...but anyway, i think a valve from another gun would be the best bet. My first thought is another airtech 2k, because i have 7...but i'm sure there are others. Has anyone tried a powerclip valve? They might be different.

Others that come to mind.
SM 750
Switch Shots(any of them)
SSPB/STS
How about a check valve?

Edited by texmustache, 28 August 2004 - 08:22 PM.

[ompa]

Vintage- nice valve choice, it looks nice and would fit the application perfectly, but it'd be so bulky to install onto the AT2k... And Texas, the PC valve is basically the same as the slow release valve on the RF20 valve, but stuck on the open position. At least I'm pretty sure.

You COULD use the air chamber from another AT2k as the valve, but then you'd need a pin sticking out somewhere to pull- and it'd be even bulkier as well. Besides, I don't have any AT2k's left to spare, nor if I get another one do I want to strip it for parts- it's such a great gun, I'd just brass it and keep it. But if you have 7 of them, please go ahead and do it, I want to hear how it works out.

Texas, the Check valve is a maybe? This is what I THINK would happen- when you pump it, it'll let the air through to the tank. But then it'll keep it from flowing back. when you fire it, the pressure in the air chamber would drop, drawing air from behind the check valve back into the air chamber, then sealing it again once the pressure equalized. If it worked like this, it MIGHT be a good idea, but you would still waste air unless you had a quick trigger finger, as the lower pressure in the air chamber would just keep drawing in air from the other side of the check valve, wasting air.

~ompa

Edited by ompa, 28 August 2004 - 08:26 PM.

[texmustache]

Bulky i don't mind...i have my airchamber on top! But does anyone know how the SSPB valves work? I don't think nerf made any valves intending them to work both ways.

[Vintage]

Yeah, it is bulky. At least if you are trying to fit inside the gun casing.

Ok, I just finished trying the crimping method. It works! Perfectly! You don't need a fast trigger pull, because the air doesn't go through the crimp that fast.

I attached a makeshift crayola barrel to the valve output, and got 60 feet flat. I think I could get much more with brass, though. I still plan on innertubing the gun. We want it just as powerful as a standalone AT2K.

Edit: I think an SSPB would not work. It sacrifices the air in the first tank to release the air in the second. Unfortunately, the "air in the first tank" would be the entire RF bladder!

~Vintage

Edited by Vintage, 28 August 2004 - 08:42 PM.

[ompa]

Sorry, I was preoccupied and can't read correctly Vintage. Anyways, how are you getting more distance than me? Just wondering, considering I'm using 6 inch brass barrels on the turret. It can't be that the crimping is resulting in better range.. can it?

~ompa

Edited by ompa, 28 August 2004 - 08:48 PM.

[texmustache]

Add another inner tube or 2 i'd say. On 30 pumps you aren't getting much elasticity, especially using the 2k pump. For a full pumping, you should expect at least 4 shots of very good power, as it stretches the bladder a lot more.

[ompa]

Well I WOULD do more pumps, except I'm currently using a bike clamp, which is not meant for these things, and 30 pumps is the max I can get. I'm getting 4 decent shots, but I know that if I pump it more I MIGHT get better distance... Vintage, how many times are you pumping yours?

~ompa

[texmustache]

Oh then you need a better clamp. I'm using a heavy duty steel one now, and i can pump it full safely. For a 2k pump you need 50-60.

[Vintage]

I have my bladder attached to the pump and the RF main valve, and the RF valve attached to the 2K valve. I hotglued a PVC barrel (with a crayola inside) directly onto the 2K valve.

To fire, I pumped it about 15 times just to get the bladder inflated. I then crimped the tubing, held down the RF valve pin, and pulled the 2K pin. I dont know what could be different. Maybe having less tubing all over the place factored in, maybe the crayola barrel added an extra degree of constriction. Maybe it was the dart itself (2 1/2 inch stefan with two bbs in the tip). Here, I will go and try a bunch of shots just to compare...

~Vintage

[ompa]

Hm... I'll re-test mine, as maybe my eyeballs just don't work properly. I'll check mine in a minute, soon as I finish up doing chores that my parents want me to do. Yeah, damn chores. Damn bike clamp. Damn other things that I'm kind of lazy to type out.

~ompa

[Vintage]

Ok, I just fired off a few more shots. That first shot was not a fluke. All of them went just over 60 feet. This is now on 20 pumps with the crimp in the tubing.

Maybe I will be able to take a picture of the setup and post it.

~Vintage

[ompa]

My 6inch barrels are consistantly getting 50' flat. I think shorter barrels are necessasry. Also, I think the Crayola's constriction also helps range, since it releases air slower than most guns- at least so it seems for me.

Tests prove it: My shorter barrels are getting about 60' consistantly flat, with about a 2' skip. I think constrition is a must- I'd say go nested brass, with .7inches of 17/32 and 4inches of 9/16. I'll try it in a few minutes.

~ompa

Edited by ompa, 28 August 2004 - 09:36 PM.

[Vintage]

Sounds good. Do you still have the layers of tubing over the bladder?

By the way, to hold the bladder on, I used a pipe/hose clamp found in the piping section of Home Depot. It's metal with a little screw that you use to tighten it. I think this is what you will need.

~Vintage

[ompa]

I know the type of hose clamp I need- I've used them before to help my dad fix the plumbing in the house... I'm testing the nested barrel as we type, I'm expecting much better results.

And yes, I still have the layers of tubing on. I do believe that the original barrels were just too long.


EDIT: Gah, sorry guys, my pump tube -> bladder connection is bad, and everything is kind of hot-glued down. I've spent wayy too many hours, getting yelled at in the process, on this gun. I'm going to put down working on it until Monday, as I don't feel like touching the cursed thing for a while. I'll still try stuff if people ask me and such, but no more self-improvements until Monday. Keep me updated- good luck on Sunday guys.

~ompa

Edited by ompa, 28 August 2004 - 09:59 PM.

[THIRST]

Guys, inner tubing that bladder will completelly negate the effects of restriction. It wont pressurize nearly as much as just making the air go out faster, not something we want if were trying to regulate the air. Sorry I havnt posted, Im at a friends house, just wanted to check in on progress while he's playing some guitar.

Hose clamp = perfect seal.

THIRST

[Vintage]

Are you sure, Thirst? If you read back a few posts, I am regulating the air with two crimps in the vinyl tubing. That provides very little airflow at that point. I think that with even the added pressure of the bike tubes, it would work.

Your first design would not work with bike tubes. That's because the liquitron gauge isn't restricting the airflow enough. If you find another 2K to work with, try using vinyl tubing. I used the tubing that came with the RF20.

~Vintage

[Crankymonky]

I am going to make one, using the same design as thirst's first one, then make a smaller restriction using brass. I may also make a valve from that brass. I will use inner tube rather than the RF20 bladder.

[Vintage]

Good for you. We need a cheap alternative to the RF20 bladder, to have a CPS system for all repeater homemades. I intend to also build a tank out of bike tubing for use on other projects.

I still recommend crimped vinyl tubing for the restriction, though. Smaller brass shouldn't do to much to help you there.

~Vintage

[ompa]

Brass gets to quite small sizes, I think it would work using the smallest size.

~ompa

[THIRST]

I designed a inner tube cps the other day, quite simple. It can use teh rf20 mechanism also, but fit a small section of 3/4"pvc on either side of the bladder, endcapping one side. Clamp both sides. The do whatever you want with the other side, wether attaching it to a coupler, or sanding down the rf20 mech and shoving it in there.

Vintage, if your using an inner tubed with crimped vinal, I may be wrong, but it makes sence for the pressure to either widen that vinal and undo the effects of crimping untill the pressure goes down, or just spew that air out faster because of the high pressure and low space. Just post resutls when its done.

THIRST

EDIT: I was using my 2k today, and was pissed to find that on 50 pumps, I got 4 shots. 5 if I really have a quick finger. Anyways, If I want it to be worthy of anything, Its gonna have to be better. 1st of all, I made a 2k turret with 4 cpvc barrels--I got rid of that copper breech, only because it had slower rof. I would use my copper, but there was no way it was fitting in those barrel stubs. I then BIC pen modded the gun with a straw, and made it into a hair trigger. Then, I opened up the liquitron and poured a lot of plumber goop in, with a very, tiny zip tie, smallest I could find, I shoved it down the liquitron, to make a hole through the plumbers goop. Some of the plumbers goop went down the liquatron, further making the airflow worse, but noweher near the tubing, so I got what I wanted out of it. So now the air comes through a small hole in the plumbers goop. I'll update you guys tomorrow when it dries, but Im hoping I can get a lot more effieciency. I was bored, so I had to do something until I can get my hands on another 2k. Also, updating on what may be the final product, of which I have no 2k, the entire rf20 mech is clamped, vinal tubed, and done, just waiting on a 2k. Also the rcsb barrel is done.

Keep it coming guys!

Edited by THIRST, 29 August 2004 - 03:12 PM.

[Hunter]

Sounds great, Thirst. I look foward to the finished result, especially with an RSCB. A true semi-automatic, once pumped all you need to do is tilt it foward. Would the RSCB interfer with the bladder, or have you relocated it? The plumber's goop sounds a bit risky, although if it works, it would be easily accomplished without buying more parts, ect. I may try this design out, I haven't worked with much air tank technology yet...

[THIRST]

Im doing the plumbers goop thing with the 2k I already own, and it isnt too risky, because I have a small hole in there, and if it doesnt work, I can take it out without much hassle.

I plan on using the rscb on the next 2k im doing(also may be final product), which I have all the parts made and everything, just need a 2k. Also, it will be completely different, along with the tank placement.

THIRST

[ompa]

Back placement! It's alot more comfortable than you might expect. Plus, the back part actually holds the bladder in place if you do it right.

Mine is still semi-leaking, so I'll fix it tomorrow. For now, I'm working on something else.

~ompa

[Vintage]

Well, I did some tests, and you were right about the weakness of the tubing connections in the RF mech. Adding pressure to the bladder popped one of the vinyl connections. Thankfully it was one of the connections to the RF valve which I meant to take out anyways. I just need to find a way to secure the tubing to hold the pressure of the extra bike tubing.

I think I will try some epoxy. After I get good results, I too will use the RSCB barrel.

~Vintage