Introduction: The Kinno-2: a Semi-Automatic K'nex Gun

About: Sometimes it takes a man to push beyond what he thinks is possible before he realizes that possibility is a mere conception of the mind. Once that barrier is broken, the mind is no longer a hindrance, but his…
Greetings fellow iblers!

Kinetic here with the second version of a gun that Innovanna and I have been working on for the better part of the summer: The Kinno-2!  

The Kinno-1 was a revolutionary gun based on a concept conceived by Innovanna over a year ago.  The idea was of a removable power source that could be used to fire off bullets by utilizing an extremely efficient "sling" firing method.  This power source functions by housing 8 pre-strung rubber bands, pulled tight and wound a cog that is held in place by a small ratchet.  This ratchet it what is referred to as the "master ratchet" because it has the most direct control of the cog (we call it the fly wheel, there are two: one in the magazine and one in the gun).  If the master ratchet is released, all the bands would fire off uncontrollably, ruining the semi automatic effect.  That is where the rest of the gun comes in.  There is another fly wheel on the gun that controlled by an escapement ratchet, a ratchet that will only allow the fly wheel to rotate a small amount with each trigger pull.  Once the band magazine is loaded into the gun, the fly wheel in the mag interlocks with the fly wheel in the gun.  Because they are now interlocked, the release of the master ratchet no longer sets off all of the rubber bands, but rather shifts control of them to the escapement ratchet, and thus the user has the ability to fire one band off with each trigger pull.  There is also a second magazine, the bullet magazine, that houses the gray connector bullets that this gun fires.  Every time a rubber band is set off, it catches the bullet, slinging it on its way while the band remains in the gun until the band magazine is removed.  

Sorry such a long and likely boring explanation, but I just wanted to let you know exactly what it is that you are going to be building.

So let's take a look at the pro's and cons shall we?


-Semi Automatic (very high rate of fire)!

-45 to 55 feet in range.

-8 (although I recommend 7) shots.

-Removable band magazine (power source) and removable bullet magazine (ammo source).

-Master ratchet now locks in place!

-Nearly unbreakable escapement ratchet.

-Clean design.


-Magazines (especially the band magazine) are rather piece consuming.

-Two magazines must be loaded for the gun to fire, not just one.

-The gun will fire upon release of the trigger, not upon the pull.

-One modified piece and some electrical tape required for the bullet magazine (other magazines can be used though).

Enjoy the video:

Special message:

This is going to be the my final K'nex gun.  I am in college now, and while it is an amazing experience, it requires a lot of time and effort.  However I now have access to tools and means of building far more complex than K'nex, and thus my possibilities have been greatly multiplied.  I will be back, but with creations far more advanced than anything you have seen thus far.  So keep an eye out!

So, for all you K'nexers out there, for the last time, Let's Get Building!


Step 1: The Handle

Each number corresponds to each picture with respect to order of appearance.  Take time to read each explanation.

1.  The handle.  Simple yet comfortable, this handle provides a solid connection between the shooter and his gun.  Also includes the trigger guard.
2.  The exterior plates of the handle.  Build these.
3.  The interior layer of the handle.  Notice the protruding white connector on one of the plates, highlighted by an image note.
4.  The center layer of the handle.  Take care to include all white rods, as they are what hold the handle together.
5.  Place an interior plate on top of one exterior plate as shown.
6.  Place the center layer as shown, so that the white rods  extend through both the exterior and interior layer.
7.  Place the second interior layer as shown, attaching it via a white rod as highlighted by image notes.
8.  Place the final plate as shown.  It may seem as if the handle will fall apart, but this will stop once attached to the rest of the gun.

You are done with the handle!  Move on the next step if you want to start building with the big boys!

Step 2: The Trigger Mechanism and Trigger Housing

Each number corresponds to each picture with respect to order of appearance.  Take time to read each explanation.

  This is the trigger mechanism.  It consists of a very strong two-part escapement ratchet, along with a cog that we call "the fly wheel".
2.  The external plates of the trigger mechanism housing.  Take care to include all the protruding blue rods, located on one plate.
3.  The internal plates of the trigger housing.  Notice the blue rod protruding from one plate.
4.  The center layer.  The mechanism consists of the fly wheel, the trigger, and the two parts of the escapement ratchet.
5.  Connect one of the internal plates to the external plates as shown.
6.  Add a black (or green) rod where shown.  Location is highlighted by image note.
7.  Attach the center layer.  
8.  Attach the final internal plate.
9.  Complete with the final external plate.
10.  Attach a small rubber band where shown.  Make adjustments depending on how smoothly the fly wheel rotates.
11.  Another view of the band placement.

You have completed the trigger mechanism!  The most difficult part of the build is behind you!  Let's move on to the band magazine release mechanism!

Step 3: The Band Magazine Release

Each number corresponds to each picture with respect to order of appearance.  Take time to read each explanation.

 The magazine release mechanism.  A very simple, yet very effective little mechanism.
2.  The external plates of the release mechanism.  Notice that one has protruding rods while the other doesn't.
3.  The internal layer of the release mechanism.  Make two of each part shown.
4.  The center layer.  Prepare these pieces.
5.  Attach the two pieces of an internal layer as shown.
6.  Attach the center layer as shown.  The blue clip serves as a locking mechanism for the master ratchet.
7.  Attach the parts of the second internal layer.
8.  Attach the final external layer.  
9.  The parts that make up the lock itself.
10.  Put them together as shown.  
11.  Side view of the part you just made.
12.  Now insert the lock you just made into the housing as shown.
13.  Push the lock in.
14.  Place a doubled up small rubber band as shown.
15.  A side view of the band placement.

You have completed the Band Magazine Release!  Let us proceed to to the fake barrel...

Step 4: The Fake Barrel

Each number corresponds to each picture with respect to order of appearance.  Take time to read each explanation.  

1.  The fake barrel itself.  A very simple build, the fake barrel does not actually serve to directly guide the bullet, hence the term "fake".
2.  The two external plates of the fake barrel.  Be sure to include the blue rods on one of the plates.
3.  The internal and center layers of the gun.  They are exactly the same, so don't worry about what they are called.
4.  Attach the internal layers as shown.
5.  Top view-just for further clarification.
6.  These parts make up the part that actually keeps the magazine in place.  Make 'em.
7.  Put them together as shown.
8.  Top view.
9.  Attach it to the rest of the fake barrel as shown.
10.  Attach the final external layer.

You are done with the fake barrel!  Now all we have to do is build the magazines!

Step 5: The Band Magazine (power Source)

Each number corresponds to each picture with respect to order of appearance.  Take time to read each explanation.

1.  The band magazine serves as a the source of power for the gun.  It has a capacity of 8 bands, although I use 7 because there is a chance that bands can snap if wound too tight.
2.  The external plates of the band magazine.  Take care to include the blue rods on one of the plates.
3.  The internal layers of the band magazine.  
4.  The center layer of the gun.  Notice the white rods protruding from the plate.
5.  Attach the internal layer to the external plate as shown.  One of the wheels is not attached to anything, and will be held in place by the center plate.
6.  Attach the center layer.  Includes the fly wheel.  This will hold the wheel mentioned earlier in place.
7.  This is the master ratchet.  It consists of two tan clips, a gray (or red) connector, and a white rod.
8.  Attach the second internal layer along with the master ratchet.  
9.  A closer view of the ratchet's placement.  Disregard the fact that the blue spacers are missing.  
10.  Attach the final external plate as shown.
11.  Attach a blue clip (or anything that will take up this space) where shown to reduce movement of the fly wheel.

You have completed the Band Magazine!  We will go over how to load it later, so let's move on to the bullet magazine...

Step 6: The Bullet Magazine

Each number corresponds to each picture with respect to order of appearance.  Take time to read each explanation.

The bullet magazine.  Utilizes a unique internal pusher system, although it does require one modified part as well as some electrical tape to function correctly.    Its non-symmetrical layout will require to me label each layer differently, but I will be as clear as possible.
2.  The backplate of the bullet magazine.  Be sure to include the two protruding white rods.  
3.  The walls and magazine pusher.  Build 'em.
4.  These are the pusher guides.  If you can, use ball-joint sockets instead of one slot gray connectors.
5.  Gather these pieces.  Notice that the right part of the tan clip has been removed.  
6.  We are going to tie the band to the gray connector.  Start by threading the band through the hole in the middle of the connector.
7.  Bring the band around through the open part of the connector and thread it through as shown.
8.  Pull the band tight.
9.  Place the tan clip in the center hole of the connector as shown.
10.  Connect the magazine walls and place the magazine pusher as shown.
11.  Attach the pusher guides as shown.  If using ball-joint sockets, snap them around the white rods.
12.  Slide the piece made previously around the green rod as shown.
13.  Snap it around the other green rod so that the tan connector attaches to the lowest middle hole in the pusher.
14.  Gather the parts for the top of the magazine.
15.  Place the gray connectors with the black (or green) rods as shown.
16.  Place the outer part as shown.
17.  Lay the piece you just made over a strip of electrical tape as shown.
18.  Wrap electrical tape around to secure the pieces together.  Be sure to pull the tape tight.
19.  Attach the completed upper magazine to the rest of the magazine as shown.
20.  Gather these pieces.
21.  Attach them on the front.
22.  Attach them on the back as well.
23.  Loop rubber band around blue rods as shown, adjusting the tightness as needed.
24.  You may need to add a rubber band on the other side to compensate for the tension.
25.  If you aren't using ball-joint sockets you will have to secure the bottom of the guides with a rubber band.

Well, that one was more extensive than I had predicted, but pat yourself on the back because every component has been made.  Let's put the rest of the gun together now...

Step 7: Putting It All Together

Each number corresponds to each picture with respect to order of appearance.  Take time to read each explanation.

 Obtain the handle and the trigger mechanism.  
2.  Connect them via the connection points shown here.
3.  As well as the connection points shown here.
4.  The combined handle and trigger mechanism should look like this.
5.  Now obtain the band magazine release.
6.  Attach it via the connection points shown here.
7.  The trigger mechanism and handle, combined with the band magazine release, should look like this.
8.  Now obtain the fake barrel.  
9.  Attach it via the connection points shown here.  
10.  This is what the final product should look like.
11.  Attach this rubber band to the trigger as shown.

Congrats, the gun is now complete!  We just have to go over loading and firing and you can start shooting this thing...

Step 8: Loading and Firing

Each number corresponds to each picture with respect to order of appearance.  Take time to read each explanation.

We will start with the band magazine.  Eight bands will fit on the mag, but they may begin to snap at that point.  For this reason, I recommend using seven.
2.  Loop your first band around the extruding green (or black) rod as shown.
3.  Pull the band over and around the two wheels in the front of the magazine, making sure that it is still hooked on the green rod as shown in step 2.
4.  Pull band all the way back and hook it on the fly wheel.
5.  For reliability reasons, make sure that the band hooks on the connector portion, not the rod portion.
6.  Rotate the fly wheel backwards (clockwise, from this view) until the ratchet clicks twice.
7.  Repeat steps 2-6 for the next six rubber bands.  You are done loading the band mag!
8.  Now we move on to the bullet magazine.  It holds eight gray connectors.
9.  Pull down the mag pusher by the tan clip.  Pull down enough to fit one gray connector in.
10.  Load one gray connector.
11.  Repeat steps 9 and 10 until you have loaded all 8 connectors.
12.  Place a green rod as shown to lock the magazine pusher in place.
13.  A view of the green rod's placement from the other side.
14.  You are done loading the bullet magazine!
15.  To load the band magazine, place the band magazine in the gun as shown.
16.  Top view.  Make sure the protruding part of the gun is between the two wheels.
17.  The magazine should be in this position.
18.  Push magazine down until it hits the magazine lock. 
19.  Give the magazine a final push so that it becomes locked in place. 
20.  Release the master ratchet and lock it in place.  Make sure that the band magazine is secure before doing this, or else your fly wheel will release all its bands simultaneously.
21.  The gun with the band magazine should look like this. 
22.  Now ready your bullet magazine.
23.  Insert the bullet magazine into the gun as shown.  Friction will hold it in place.
24.  Remove green rod to release magazine pusher and begin feeding bullets.
25.  Your gun is now loaded and armed. 

Congratulations!  You have made your very own Kinno-2!  Simply pull the trigger to fire.  Special thanks to Innovanna for the concept and for helping me with the design of this gun.I'll be back soon with some all-new designs and creations!