Airosft AEG to HPA Mod Conversion

[Kuba_T1000]

Hi,

I'd like to present my latest project. It's airsoft V2 gearbox modification to gas system version.
The greatest advantage is regulated ROF and FPS.
On my Website are free project files to download - 3D model designed in Solidworks.

Take a look at the promo-video and some pictures below:

[youtube][/youtube]

[Crna Legija]

man that video is great, did you make it?

your site is a little hard to navigate, but your stuff looks amazing. what pressure does it operate at?

[Kuba_T1000]

I adapted this video to my requirements 8)

It operates at 6 to 14BAR.

[Crna Legija]

It operates at 6 to 14BAR.

dam i was hoping to hear 30 bar

[Kuba_T1000]

if I would have a solenoid that can operates with this pressure, so my mod should work

[POLAND_SPUD]

great stuff as always.... care to post more diagrams ?? how does it work ? no wypilem 200 g i teraz nie bardzo kontaktuje

[jackssmirkingrevenge]

Interesting. If I understood correctly, the spring piston is replaced by a blow-forward bolt, which is fed with pulse air from a solenoid valve controlled by that magic box to vary rate of opening and opening time.

Some questions:

- what sort of fps and rof are you getting?

- is the added bulk of the valve system, power supply and gas supply worth the power ?

- do you plan on having everything gun mounted, or in some sort of backpapck?

[Kuba_T1000]

Electronic unit controls the solenoid. Using two potentiometers you can control solenoid (opening, closing times) I used a NE555 timer. Solenoid and electronics are powered by 12V battery.
Air pressure from solenoid goes to cylinder and moves the piston and after a while shoots BB Pressure drops, and piston goes back to start position. System is ready to next shot.

Rof is regulated -> typically 3-20 RPS. 20 BB/sec are possible with low pressure 7-8BAR. With high pressure (14BAR) I get 15-17BB/sec.
Personally I'll put this to backpack. But if you want you can use a full stock of gun.

FPS are pressure-dependent and dependent of barrel length. I get about 480FPS with 40cm barrel long.

I think it is worth to use it, becouse in very simple way you can adjust FPS, ROF and you can eliminate typical high-speed motor sound.

Much more pictures, shooting tests and also Solidworks draws are on my Website:
http://kuba-t1000.com/minigun/index.php ... ersion_mod


[youtube][/youtube]

[al-xg]

So the solenoid valve is actually venting between shots ?
Did a 2/2 valve make the cycle too slow ?

It would be amazing if the valve could be fitted inside the gearbox.
I'm guessing you've probably already put quite a bit of thought into that

What is the second O-ring on the piston for ?
Can air in front of the piston escape or is it used as an air spring ?

[Kuba_T1000]

Yes, 3/2 type solenoid has a venting output, and 2/2 valve would make cycle too slow. I used 2/2 type solenoid in my first version - video is on YouTube. As you can see it's too slow.

Yes, it would be amazing, but it's almost impossible. Mini solenoid has too small air-flow.

Second piston o-ring is needed to stabilize piston in the cylinder.

[jackssmirkingrevenge]

I like the idea of using an existing airsoft shell, however having to carry an air supply and electronics seems a little too bulky - have you thought of replacing the solenoid using a pop-off valve directly or pop-off piloted exhaust valve in order to pulse the air to the bolt? It could also be mechanically adjusted for power and ROF by altering pop-off pressure and valve flow respectively.

With some effort you could make the bolt itself the valve:

[Kuba_T1000]

Good idea, but it complicates ROF and FPS control.
I'll think how to integrate it to gearbox shell.

[jakethebeast]

i actually thought that if you could make it to example, AUG, you would have plenty of space to put the solenoid inside the gun

[al-xg]

Good idea, but it complicates ROF and FPS control.
I'll think how to integrate it to gearbox shell.

http://www.zdspb.com/tech/misc/anim_spool.html

The mechanical unbalanced spool valves are basicaly JSR's drawing with a sear. The sear could be controlled by a solenoid for ROF.

Does FPS have to be controllable on the fly ? If not the feed pressure could be set on the regulator. Often how its done on paintball guns, even electro-pneumatic ones.

Although FPS could also be controlled by a solenoid on the fill side, controlling the little pin, at a set feed pressure, more time open=higher chamber pressure.


The electro-pneumatic versions obviously allow more control offer the firing and even though they still require a 3/2 solenoid valve, would require a much smaller one, as it is not the main valve.

[Mr.Sandman]

Hate to tell you this, but polarstar airsoft beat you to this about 2 months ago....www.polarstarairsoft.com