K'nex Elastic Band Gun

Introduction: K'nex Elastic Band Gun

After 80 long minutes of research and development, I have somewhat perfected the elastic band gun using only regular parts from K'nex (mostly because it's what I had on hand).

This gun can hold 6 elastics comfortably, and has a semi auto mode and a shotgun mode.

Step 1: The Pieces...

Here is what you need.
2x long orange posts (try to get the ones with locking ends. Red ones ok but you may have issues).
7x blue posts
8x white posts
15x green posts
3x gray 2 point connector
3x white 8 point connector
5x yellow 5 point connector
6x green 4 point connector
2x blue 7 point connector
3x gray 1 point connector
2x gray long spacer
3x blue small spacer
2x orange 2 point straight connector
2x wheel connector hubs
1x orange t - connector
1x small elastic
tons x thin elastic bands

Step 2: The Important Parts

The most important pieces in this build is the T - connector, the small elastic and the orange posts with the locks at the end. You could make it without, but then the gun will shoot all elastics at once.

Step 3: The Heart of the Gun, the Trigger.

Here is where it all happens. You can modify the rest of the gun, but this peice is essential. It forms the trigger and ratchet assembly.

Step 4:

Make two of the white pieces shown here. Then stack them using a blue post like this:
- wheel hub
- white piece with blue pole to the right
- gray 1 point connector
- blue spacer
- super lovely trigger assembly, white pole down
- blue spacer
- gray 1 point connector
- second white piece with blue pole to the right
- wheel hub

Now align the white poles of the white assembly with the top green stud of the trigger, and attach another blue pole across the whole thing including the gray 1 point connectors. This is really hard to push in so you might need an adult or a hefty kid with big hands.

I suck at describing this, so just look at the picture.

Step 5: The Spindle

Here you are making the place where the elastics will be loaded. first make two green assemblies like the one pictured here.

Now we stack pieces again, but this time the first piece is snapped on top of the blue pole. The rest is slid on, then the last piece is snapped on:
- green assembly (snapped)
- gray spacer
- white 8 point connector
- gray spacer
- second green assembly

Again, the assembly is really tight so you might need a Baba, one who makes perogies all day or works in a meat packing plant, to help you.

Finally, attach the spindle and trigger assemblies together. The teeth of the white spindle should come between the green stud and orange t - connector of the trigger.

Step 6: The Barrel...

To create the barrel assembly connect the two long orange poles together with an orange straight connector. Then connect a white pole to the other orange straight connector, slide a blue spacer on, slide the first orange straight connector and finish by sliding a gray one point connector down the orange pole and snapping it to the end of the white pole. This is where the elastic bands will fire from. connect the barrel to the spindle assembly at the yellow connectors.

Step 7: The Back...

Really all this piece is for is to start the handle of the gun. Attach the two 7 point connectors together with two blue poles and then attach them to the back of the spindle assembly.

And don't think I was dissing anyone's Baba in the previous step. I do in fact have a Baba that made perogies all day and another grandma that worked in a meat packing plant called Gainers. Hands like vice grips.

Step 8: The Handle...

This is probably the only part I don't like about this gun. It seems unfinished to me. I welcome all modifications to make this better. It does conform to my hand quite nicely though.

For the front, attach two yellow 5 point connectors with white poles and then attach two green 4 point connectors at the tops. Just look at the photo. Attach that to the green studs of the trigger assembly.

For the back, attach two green 4 point connectors with two gray 2 point connectors via green studs, then put the last two green studs at the top. connect that to the blue 7 point connectors at the back.

Step 9: The Elastic You Won't Shoot

This is a critical detail, otherwise you won't like the gun. And if you made it this far that would be a huge waste.

OK remember the little elastic band in the first picture? You need to wrap it from the blue pole the husky kid pushed in for you on the trigger assembly, behind the trigger, and onto the other end of the blue pole. This keeps the trigger tight.

Step 10: Terrorize Your Neighborhood...

You can now load and fire your gun. To switch between modes of fire, move the t - connector out of the way to shoot all of the elastics, or keep it in the way for single shots.

Fair warning, don't point this thing at your kids when loading in case you let go prematurely, and zap him in the neck. It will not be a bonding moment. True story.

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    3 Discussions


    5 years ago on Introduction

    I don't think it looks too good, but it looks really comfortable and it's awesome how it can shoot!