DYI AEG Recoil Engine

[DesertFoxRomel]

Ok, so I read all these threads about AEG Blowback, TM Recoil Engine etc etc, and wondered why most of them were not main stream or popular? In addition, I thought of a way to make a DYI version

 

Some guns modified to have some sort of blowback/ recoil rely on a bolt attatched to a piston, which is ingenious, but could also stress the gearbox and possibly strip the piston. So I thought of an alternative:

 

For example, this device could be put into pretty any gun, in the stock, handgrip etc. Assuming if the gun was a M4, it would go into the buffer tube.

 

How it would work is that the wieght, made of lead or steel, is glued with permanent magnets, such as Neodymium magenets *aka rare earth magnets*, would be inside a tube, such as a buffer tube in the stock of a M4. Now, on each side, will be strong electromagnets, which is powered by the main battery of the AEG, and timed with switches placed around the mechbox, such as the window where the piston moves near the rear of the GB, or on the tappet plate. Now, when the gun is fired, the piston is cocked on the return stroke. As it reaches the half way point, the electromagnets will turn on and pull the wieght towards the shoulder of the shooter, creating a sensation of recoil. Just before the piston reaches the rear of the GB, the wieght will go foward, creating a foward stroke of recoil. When the piston fires the BB, the Wieght will remain stationary to avoid affecting accuracy.

 

Now, if such a gun is made/ modified, there are a few improvements that would make the gun better as a whole:

1. Have a precocking set up to increase accuracy, reduce trigger lag, and make the timing of the recoil mech more realistic

2. Have a last shot bolt stop, like in RS M4s, Systema AEG, etc. I have an idea on how this should go, will post a illastration later.

3. Reduce the overall wieght of the body of the AEG, and compensate the wieght lost by adding more wieght to the recoil wieght. This would, in theory, make the gun have more recoil.

4. Have a MOFSET circuit for wiring

5. Have the recoil mech activate after the BB is fired to increase accuracy

the obvious benifits would be

1. Recoil

2. Unlike GBB, no gas to buy/ fill/ inhale

3. Charge and go like with other AEGs

4. If a switch is added to the mechanism, the recoil mech can be switched on or off

 

only downfalls are:

1. Less battery life

2. One more thing to worry about or potentially fail

 

 

Now, unfortunately, I do not have the resources/ time to make one at the moment. I have seen the works of the talented modders/ builders of this fourm, and I would love to see my idea be made into a reality, and make a guide for others to follow. So if you have the time and recources to make it happen, please consider my idea ;D

[mattmanic]

I can't imagine you'd be able to get the magnet switching fast enough for an aeg and if it was too powerful might it interfere with the motor?

[DesertFoxRomel]

^thats a very valid concern, but if the wieght's travel is less than a Inch or two, I think it will do fine. Depending on the strength of the electromagents, I think it will be able to match the ROF of a AEG, assuming its not insanely upgraded to 1000+ ROF. Also, adding some springs may help with this potential problem and or increase the recoil effect.

 

and depending on the placement of the magnets, I don't think it will interefere, such as the buffer tube, it should be far enough from the motor to affect it.

 

after some thought, after seeing this thread, it is possible he is using a similar system, which would make this idea more than impossible.

 

http://www.arniesairsoft.co.uk/forums/inde...howtopic=132961

[Ascendance610]

if the surrounding metal (IE the buffer tube) is magnetic wouldn't it mess with the cycle?

[-FIDO-]

dont think it would work because of the magnets

heat or impact will destroy the magnetism inside a magnet....mate im not exactly sure if thats the case with neodymium too, but if it wont loose its magnetic effect from hitting against the other magnet, it will fall apart..it has identical characteristics to ceramics thats why...

but ok, maybe there is a magnet out there that can do this job...shaking and hitting around and wont break into 1000 pcs

 

if the surrounding metal (IE the buffer tube) is magnetic wouldn't it mess with the cycle?

 

 

as far as i know the tube is pot on most of the airsoftguns...so non magnetic

and if its aluminum on some guns, it wont be magnetic either as AL is magnetic neutral

[Lance Jackass]

This looks vaguely familiar...

 

i used to be obsessed with the idea of using a solenoid inside an AEG gearbox. It would get rid of the need for gears, motors, semi auto cut off levers, pistons and springs. The only thing stopping my brilliant plan, was that it would be physically impossible to get enough "oomf" from a solenoid on small voltages, with small magnets.

[MDK_Marshal]

Hmm....

 

This gives me an idea for a slightly simpler system. Rather than have another electromagnet pulling the rod back and forth, perhaps just a magnet pulling it one direction and a spring pulling the other?

 

Give me a minute and I'll have a ponder at the buffer tube I've got in my bits box and a quick fiddle with some parts, see if i can figure out a way to make this feasible...

 

EDIT: LJ, Genius man! I too was obsessed with solenoids, but this gives a good idea to me!

 

We don't have to worry about it pulling a huge spring or anything, so power is greatly reduced. A small spring, say, pulling it towards the rear. Solenoid Magnetizes, pulls the magnet forwards, then power is cut, and the magnet (and weight attached to it) gets pulled back to the rear with some oomph.

 

Or, something along those lines, in any case. probably better to have the magnet attracted to something at the back, which would let it return faster, giving more recoil...

[Yuri]

You know there's no such thing as a magnetic monopole, so your drawing doesn't really make any sense.

 

The easiest way to do this would be some sort of solenoid and spring configuration. However, I doupt you would be able to get any considerable recoil out of it without switching to something like a car battery. In other words, what Lance Jackass said.

[DesertFoxRomel]

dont think it would work because of the magnets

heat or impact will destroy the magnetism inside a magnet....mate im not exactly sure if thats the case with neodymium too, but if it wont loose its magnetic effect from hitting against the other magnet, it will fall apart..it has identical characteristics to ceramics thats why...

but ok, maybe there is a magnet out there that can do this job...shaking and hitting around and wont break into 1000 pcs

 

Steel magnets yes, ceramic maybe, but my phys teacher said that neodymiun magnets will not lose their magnetism when subjected to high impact. In addition, the wieght should be padded if using anything other than Neodymiun.

 

You know there's no such thing as a magnetic monopole, so your drawing doesn't really make any sense.

 

The easiest way to do this would be some sort of solenoid and spring configuration. However, I doupt you would be able to get any considerable recoil out of it without switching to something like a car battery. In other words, what Lance Jackass said.

True about the drawing, I forgot to illastraight that the electromagnets do have two poles, but my point in the crude drawing is to show that the electromagnets switch polarity to repell/ attract the wieght. In addition, I am serching for Lance's thread he mentioned, and will also post later some coil technology some people cooked up, which may be in interest to this project.

[Ascendance610]

What about a piston in the stock tube, due away with magnets completely and have a 2nd motor in the tube with an aluminum piston hitting your shoulder?

[DesertFoxRomel]

^that may be worth a try.

 

ok, I found lance's thread:

 

http://www.arniesairsoft.co.uk/forums/inde...hl=solenoid+aeg

 

good stuff, still reading it, but look what I found

 

http://www.sciplus.com/category.cfm/category/144

 

http://www.sciplus.com/singleItem.cfm/term...LogFrom/froogle

 

the solenoid

12V DC, 600mA draw, and 10lb pulling force. On that note, does anyone know the amount of force required to compress a 1Joule spring?

 

 

What I am thinking is that two solenoids can be used to move a wieght or piston back and forth, making recoil or launching a BB.

[Ascendance610]

theoretically it would take 1 joule of force, but realistically it is more like 1.4 factoring in friction, air resistance, and air leaks.

[Yuri]

Joule is a unit of energy, not force.

 

To figure out the required force you could just device an experiment where you make a rig that holds the spring in place and you just pile weights on it and see how much it takes.

[DesertFoxRomel]

Ok, I have a few ideas some of you may consider doing

 

A. For an improved mech box design, how about a solenoid moving the lever of a precharged pneumatic cylinder?

 

http://www.arniesairsoft.co.uk/forums/inde...howtopic=133975

 

http://www.baikalairguns.com/

 

Ok, how that would work:

1. The solenoid moves a lever and pumps air from a large cylinder and forces it through a one way valve and into a smaller compression chamber. In theory, the proportion of the large cylinder to the compression cylinder will be propostional to the pressure. For example, if the volume of the compression cylinder is 1/3 the volume than the large cylinder, the pressure will be 3 times atmospheric pressure.

2. With compressed air inside the compression chamber, the gun is cocked and ready to fire. When the user pulls the trigger, a valve, possible a modified GBB valve, releases air and launches the BB. Due to the short stroke of the solenoid, the overall volume of air compress will probably not be equal to the volume of the barrel. To counter act the vacuume effect, the force and speed of the compress air leaving the compression cylinder should be enough to launch a BB through the barrel at a decent FPS, despite not being able to fill the whole barrel. To adjust the FPS, a screw, acting as a flow resistor, can be placed right in front of the compression chamber.

3. When the BB is fired, the solenoid cocks the mechanism again and starts from step one.

 

PCP mechanisms are used in the finest and most accurate airguns, and if use properly, I have no doubt it will be a HUGE leap in accuracy in AEG in the mechaism described above. Unlike current AEGs, it does not have pistons and gears to strip, no sewing machine noise, and no heavy piston to cock and move around during firing, reducing trigger lag.

 

 

Ok, for the recoil mech, a possible solution would to use the motor and planetary gearset from a cheap power screw driver.

 

http://hackedgadgets.com/2006/07/15/rc-screwdriver-car/

 

1. After the BB is launched, the motor switch is turned on, spinning the motor.

2. The motor moves a plate, which looks like triangles around the edge of the plate *sorry for lack of better description, will post pics later*. The spring loaded wieght, which has cooresponding trianges, does not rotate. As the plate turns, the wieght is pushed back and compresses the spring. When the plate makes a complete cycle, the pressure against the wieght and spring is released, making the wieght move towards the user's shoulder. Thus creating recoil.

 

I will post some sketches later, if some of you are interesting in trying some of theres

[X Lupin]

Would it not be possible to use that pulsator in the rifle's stock, perhaps connected to a lipo battery, and wired to the gearbox's trigger (the gun would have 2 batteries) so that when you pull the trigger, the pulsator.... pulsates and the gun shoots?

 

Of course, the recould would be off beat from the shuts, but hey, its recoil.

[TDS]

While not a bad idea, and you can definably get a good recoil from rare earth magnets, good mags have a tendency to shatter under any sort of impact, so getting it to work and not explode would be tricky.

 

//edit speeling

[DesertFoxRomel]

Ok, I have a few ideas some of you may consider doing

 

A. For an improved mech box design, how about a solenoid moving the lever of a single stroke mechanism?

 

http://www.arniesairsoft.co.uk/forums/inde...howtopic=133975

 

http://www.baikalairguns.com/

 

Ok, how that would work:

1. The solenoid moves a lever and pumps air from a large cylinder and forces it through a one way valve and into a smaller compression chamber. In theory, the proportion of the large cylinder to the compression cylinder will be propostional to the pressure. For example, if the volume of the compression cylinder is 1/3 the volume than the large cylinder, the pressure will be 3 times atmospheric pressure.

2. With compressed air inside the compression chamber, the gun is cocked and ready to fire. When the user pulls the trigger, a valve, possible a modified GBB valve, releases air and launches the BB. Due to the short stroke of the solenoid, the overall volume of air compress will probably not be equal to the volume of the barrel. To counter act the vacuume effect, the force and speed of the compress air leaving the compression cylinder should be enough to launch a BB through the barrel at a decent FPS, despite not being able to fill the whole barrel. To adjust the FPS, a screw, acting as a flow resistor, can be placed right in front of the compression chamber.

3. When the BB is fired, the solenoid cocks the mechanism again and starts from step one.

 

Single stroke mechanisms are used in the finest and most accurate airguns, and if use properly, I have no doubt it will be a HUGE leap in accuracy in AEG in the mechaism described above. Unlike current AEGs, it does not have pistons and gears to strip, no sewing machine noise, and no heavy piston to cock and move around during firing, reducing trigger lag.

 

 

Ok, for the recoil mech, a possible solution would to use the motor and planetary gearset from a cheap power screw driver.

 

http://hackedgadgets.com/2006/07/15/rc-screwdriver-car/

 

1. After the BB is launched, the motor switch is turned on, spinning the motor.

2. The motor moves a plate, which looks like triangles around the edge of the plate *sorry for lack of better description, will post pics later*. The spring loaded wieght, which has cooresponding trianges, does not rotate. As the plate turns, the wieght is pushed back and compresses the spring. When the plate makes a complete cycle, the pressure against the wieght and spring is released, making the wieght move towards the user's shoulder. Thus creating recoil.

 

I will post some sketches later, if some of you are interesting in trying some of theres

 

 

Fixed the correct termanology, I meant single stroke pneumatic, not precharged pneumatic, the later using CO2 or similar power sources for energy, rather than using ambient air.

 

 

Also, for the magnet breakage issue, it could be easily solved by using steel reinforcements, such as steel washers, and some foam padding.

[Killbucket]

All of these ideas have the same flaw: increasing the cost of a product that the public expects to be getting cheaper.

 

You ARE talking about several thousand dollars worth of design work, and all new parts to replace proven mechanicals.

Since airsoft powerplant design has become somewhat standardized, a gun with this feature would be viewed as gimmicky, not innovative.

 

Separate the idea of kick from blowback. Some new guns are rigged to move an exterior part (usually the charge handle or eject port), this is blowback. No kick is produced, and it is not difficult to add. A simple slot is put into the gearbox so the piston can move the part through a pin or lever. Adding any kind of motion device to a gun will hurt its ability to fire straight. My "Hard Kick" GreenGas DesertElephant cannot hit a damn thing realistically, but it's big fun. It's a trade-off. And it wouldn't work using batteries.

 

Airsoft batteries already suffer from low capacity...

In order to feel a "kick", you need to at least cancel the mass of the piston going forward, and then go above that to produce a discernible "kick".

In other words, more energy is required for the kick that to fire the gun (battery goes dead over twice as fast).

Solenoids have a VERY short working range(usable travel). And a very slow energize/de-energize action. In my experiments, it wasn't possible to get the solenoid to kick fast enough, especially if it was weighted significantly. And there was a secondary "kick" when the solenoid let go each time! The smallest solenoid "workable" was 1.5" in diameter. Too big for an AEG, almost too big to put in one of my Brownings, even.

 

There ARE airguns that reverse the piston, so the kick goes backwards. This is so normal rifle scopes can be put on them.

Most people do not know that a BB gun can destroy a high-dollar real-steel scope in one or two shots, as the parts are all braced the wrong direction for this.

No airsoft gun uses this design to my knowledge. This would be the better path to take.

Or just switch to .35gr metal-plated ammo, that will give you more feel to each shot.

 

EDIT: I don't know about you, but I have to try HARD not to fake the recoils myself with each shot. I even catch myself going rat-a-tatta-tat sometimes. All part of being an overgrown child..."vroom! vroom!"

[P-E]

Another..... cheaper..... simpler..... solution: http://fr.youtube.com/watch?v=_9O6h5tHqqk to add some recoil

[Killbucket]

Blowback action. Nicely done, but the cord will wear out. A teflon strip would work better.

RECOIL is the whole gun pushing back from the shot.

[my_plague_666]

i think the ideal compromise would be a 'rumble pack' style thing (like KB mentioned in another thread) it'd only really work in a gun with enough room inside and it still wouldnt be recoil as such (wouldnt be pushing back into your shoulder) but with the right sized weight at the right RPM you'd certainly get a nice feedback from it. couple that with a blowback bolt (aesthetics and to mask the noise from the gearbox and rumble packs) and you'd be looking at a nice compromise/alternative to expensive classics.