Creating an airsoft gun

[Mike Martus]

Not to be to picky but I am getting complaints about how dangerous this is to be creating "Guns" and providing info thru these forums.

While yes there are FIRST Parts involved many of us think this is not a good path to be going down.

I am getting requests to close this thread and also to remove it.

I will watch for a short while and make a decision soon unless it takes care of itself.

[Nathan]

Not to be to picky but I am getting complaints about how dangerous this is to be creating "Guns" and providing info thru these forums.

While yes there are FIRST Parts involved many of us think this is not a good path to be going down.

I am getting requests to close this thread and also to remove it.

I will watch for a short while and make a decision soon unless it takes care of itself.

Mike, the discussion is about airsoft guns, not real firearms. As long as an airsoft player wears eye (and optionally face) protection, there is ZERO danger. Anyone who says otherwise is speaking out of ignorance (I mean that in a nice way). Using power tools during the build season is a far more dangerous activity.

With that said, over the past few months I've developed an interest in how airsoft guns work and have some compiled some good links:

A brief overview of how airsoft guns work: http://www.airsoftretreat.com/review...php?product=58

A good wikipedia article about airsoft AEGs: http://en.wikipedia.org/wiki/Automatic_electric_guns

And a cool image from the above article:


An explanation of Hop Up, which is very important for accuracy: http://www.youtube.com/watch?v=0XfF9itDss0

You can buy the springs cheaply on ebay, for example: http://cgi.ebay.com/SHS-M120-M-120-M...em27b03e 0a2c

A CIM Motor its probably going to be far too powerful for what you're trying to do.

That's kinda the point.

Just remember that the power of the motor basically has no affect on the power of the gun - it's the spring that propels the BB. The motor just needs enough power to wind back the spring and no more.

I'm thinking about trying to build an AEG over the summer and will be following your progress with interest. Good luck with your project!

[Vermeulen]

Echoing the posts about not using a CIM motor, it would be way, way too heavy. Try running around with a CIM for a couple hours, even without the rest of the parts. CIMs are also bulky and have more power than you really need.

[apalrd]

In using a CIM, you are looking for power (yes?)
If you run the motor at 18v, you can use a Banebots 775-18.
My math says that, at peak power at 18v, it has somewhere approaching 500w. A CIM at 12v peak power does 350 or so. (this seems wrong to me, so I checked it, and it came out to be the same thing).

So, you want a power-dense motor, not necessarily the most powerful, (at 12v) the most power-dense KOP motor is the 2011 FP motor, with 290 watts at the size of a RS550 (smaller than a CIM or 775).

Past power, it's really just gearing to make it have the characteristics you want. As earlier posters said, the power to fire the shot is actually determined by the spring, but the motor must recoil the spring, which requires work, so a more powerful motor can do the required work faster (meaning it can fire faster).

[Biolore]

While this thread does have a lot of helpful information, my initial question of the gears has yet to be answered. Where on the interwebs might I find properly sized gears?

[efoote868]

Originally Posted by Biolore

While this thread does have a lot of helpful information, my initial question of the gears has yet to be answered. Where on the interwebs might I find properly sized gears?

You may find that you just want to cannibalize a few airsoft guns instead...

[bassoondude]

Be sure to check your state's and city/county's laws about firearms, many areas control the sale of airsoft guns, and subsequently their construction.

[billbo911]

Here is a small, light 12v option. It uses a Banebots 395 motor, but can easily be adapted to use a 540, 550 or 775 to do the same thing. This rig produces the same torque as a Denso window motor and 45 RPM more. Additionally, it is 130 grams lighter than a window motor. It should be fairly easy to adapt to the mechanism as it already exists in the Airsoft gun.