K'nex Bolt Launcher and Bolts




Introduction: K'nex Bolt Launcher and Bolts

Disclaimer: This is not a toy. I am not liable for any injury, harm, or death caused by correct and/or incorrect usage of this weapon.

A very simple bolt launche that requires very few, common pieces and shoots a good distance (distance varies with rubber band strength and weight of bolt).

The pieces I list here are the bare minimum and most pieces can be interchanged with others in case you are short on pieces. Feel free to add more pieces to it to make it more fancy, elaborate, practcal, etc.

Pieces required for the launcher:
2 orange/red
2 yellow
2 white
2 blue
2 green
2 grey/black

All connectors can be interchanged. What I list here is what I used in my version.
2 orange
4 green
1 white

2 silver spacers/6 blue spacers/2 dark grey or black connectors and 2 blue spacers
1 tan clip connector/orange rail piece

Step 1: Building the Front and Middle.

You will need:

2 orange/red
2 green
1 white
2 black

1 orange
1 yellow
2 green

Step 2: Building the Back and Trigger System.

Pieces needed:
2 yellow
2 blue
1 white

1 white
1 orange

Spacers with pieces
Orange rail piece thing/tan clip connector

Step 3: The Bolt

To tell you the truth, I have three different kinds of bolts. Unfortunately I will not show you how to make the other two kinds because (1)they are more complex, (2)they require a lot of hand/finger dexterity to build, and (3)one of them requires a material that you probably don't have access to and also requires a lot of hard labor to prepare it before it can be used as a bolt head.

This bolt is very simple, cheap, easy to build, and requires a few common household items:

3 toothpicks (preferably same size ones)
1 normal plastic bendy straw

For an instructable on how to build a better bolt, check out my Cheap Dart.

Step 4: Loading and Firing

The rubber band I used was approximately 1 7/8 inches in diameter, 1/16 inch thick, 1/8 inch wide, and has a circumference of about 6 6/16 inches.

To prepare to load, place the rubber band around the orange/red pieces in front and pull it back until it fits on the orange rail piece thing/tan clip connector on the trigger.

To load, fit the back of the bolt into the rubber band at the back snuggly so that it doesn't drop and place the tip of the bolt onto the rubber band around the orange/red pieces in the front.

To fire, simply place one hand under the green connectors in the front and around the black/grey rods. Place your other hand around the yellow rods in the back and pull the trigger (blue rod).



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    We have a be nice policy.
    Please be positive and constructive.




    huh, sweetness! :D

    can we use grey instead of black?

    can the ram penetrate cardboard

    nice, though, in the front you should put the rubber band UNDER the yellow/orange connactor, or you will get a hock of a lot more friction, wich you probably don't want ;) alty

    2 replies

    The reason that I put the rubber band over the yellow/orange connector in the front was so that it wouldn't be necessary to go retrieve the rubber band or bring out a new one each time I have to fire. If it was under the connector, it would drop each time and I would have to waste time bending down, getting it, placing it back onto the gun, then pull it back before I can load another bolt. If it was over, all I needed to do after firing a shot is to pull the rubber band back and load another bolt. Much simpler, no?

    duct tape or bind the band onto the frame to solve it

    xaio hawk, could you please post the other bolt i dea even if it is more complicated?

    1 reply

    Sure, just go to the making the bolts section and there should be a link to it.

    Does anyone want me to post my mangonel/onager? I built it recently and it works pretty well. It launches marbles, which is a very common and cheap ammunition though I think many other things can be used as ammo too.

    I would also like to know if this is what you do to every instructable you find with no comments yet.

    Can I have something more "constructive" as they put it?

    I could, and I would, but as I have said before, I like to keep mine as light as necessary. If you wish to do so, feel free to.

    lokks kind of original... in an interesting way. good instructable. not so sure about the gun.

    2 replies

    I'm not so sure whether that's a positive or negative comment...

    it definately positive now ive built it. fires well and accurately. good trigger design!