K'nex Plasma Rifle

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Introduction: K'nex Plasma Rifle

A knex version of a plasma rifle from Halo.

Step 1: Pieces

List of pieces:


Green - 22
White - 10
Blue - 12
Yellow - 13
Red - 13
Gray/Black - 12


Gray - 8
Light Gray - 38
Orange - 14
Red - 4
Green - 8
Yellow - 38
White snowflakes - 4
Dark Blue - 16


Tan Clip - 1
Black 'Y' Clip - 6
Black Socket Clip - 2
Blue and Green Joints - 2
Blue Spacers - 50
Gray Spacers - 6

This may be slightly inaccurate.

Step 2: Body and Handle

The body comes in two parts: the front half and the back half.

Follow the pictures. The front half is depicted in pictures 1-4.
1= side view
2= back
3= top
4= front

Pictures 5-8
5= front
6= back end
7= side view
8= bottom

The handle is made of 16 dark blue connectors and 3 red rods.

Putting them together comes later.

Step 3: Trigger

The trigger is based on that of the YAKG, though I have modified it. It's fairly simple to build. Follow the pictures.

Picture 4 is important later.

*Note, as with the YAKG, the orange connector does not have to be modified, but I personally prefer it that way.

Step 4: Magazine

I'm fairly certain this is original, because I haven't seen anything like it before.

For the pieces where the bullets rest (picture 5), I used decapitated grays, but a traditional rest (tan clips) works too.

Picture 6 is of the pusher that pushes the bullets up the magazine and onto the rests. The magazine has only a 4 round capacity ( I had to keep it small), and the pusher is just big enough to work.

Picture 7: To attach the pusher, rubber bands can go around white rods placed on the magazine's side.

Step 5: Bottom Half

The bottom half of the gun is purely for looks, although it does help to balance out the weight.

We'll construct it in several steps:

1. The skeleton. This is the frame around which the other parts will be attached. Pictures 1 and 2 are of the front and 3 and 4 are of the back.

2. The curve. Pictures 5 and 6 shows the bottom curve separated from the base.

3. Connection. To connect the curve to the skeleton, observe picture 7. This is how the front attaches. In picture 8, you can see how the back is put together.

4. Support. Use an orange connector to attach a gray rod to a yellow rod, then attach that to either side as a support, as in picture 9.

Step 6: Other Stuff

Here, we will build the miscellaneous parts that don't quite belong in the other steps.

Picture 1: The ram rod. Very simple.

Pictures 2: The top curve. Very similar to the bottom curve.

Step 7: Putting It All Together

Finally! Time to assemble your very own plasma-spewing machine.

1. Adding the trigger. Attach the trigger to the front of the body like in pictures 1 and 2.

2. Assembling the body: Attach the back to the front, as in pictures 2 and 3 (shown w/o the trigger so it's easier to see).

3. Attach magazine. This is a little tricky. Picture 5: magazine attaches to the front of the body. This requires a little bending of the red rods. *Note - Do not forget the yellow connector wedged between the body and the magazine. It is most easily placed while you are attaching the magazine. Picture 6: magazine attached with the trigger too (but w/o the yellow connector)

4. Supports. 2 gray rods and 1 orange connector. Place like so (this also requires some bending).

5. Handle. As seen in picture 8.

6. Top curve. Attach to the magazine like in picture 9, and to the body like in picture 10. Add 2 gray rods to the back of the curve. They stretch to the back of the gun.

7. The bottom half. Picture 11. The red rods on the side of the handle go through the orange connectors and into the yellow connectors.

8. Vertical support. Keeps the top and bottom halves rigid. Attach the top to the special yellow connector from earlier.

Step 8: Loading and Firing

The ram rod goes in the hole of the yellow connector at the back of the body (sorry for the blurriness).

Bands go on as seen in picture 2. The band for the ram rod goes through the orange connectors supporting the top curve and hook onto the black socket clip.

To load, tip the gun upside down (it should stand up), and put 4 blue rods into the magazine, then add the pusher.

To the gun, use your finger to pull back on the tan clip on the ram rod. Pull back until the trigger clicks.

Now you're ready to fry your friends with boiling plasma a.k.a. blue knex.



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I don't even know Halo but this thing looks awesome!!! Like the design. 4 stars.

you never played halo???!!! IT'S AWESOME

I can tell you that it looks like the real one and i'd give a billion dollars to build it if only i had those green and blue things

you dont need the blue and green, just use ball and socket joint

Oops, did I say that, I meant grey connectors i don't have enuf


Yayz late reply! But if i give you the cons you gimme 1 billion $ right?

 Yes. After I hack the pentagon and steal taxes, ( false comment if you're reading this american government ppls)


 Done yet?

 Nooooo, their firewall is too powerful must develop a program to fit 2 nerd's brains into the pc to do it...hmm i know just how.