How to Make a Great K'nex Weapon Instructable

So You Want to Contribute?

Ever since around September 2006, K'nex weaponry has occupied Instructables, and has been growing rapidly ever since. If you're having trouble figuring out what to post for your Instructable, take a look here, maybe you'll get a few ideas.

Before contributing to the site, please consider the following:
-The first thing you should do before contributing your first Instructable is that you should skim around the site a little. You should get used to the way the site works and comment a little, get to know some people.
-Check out this guided tour of Instructables to help you get started.
-You should ask around for ideas on how to make a great gun.
-Make some simple guns, and work your way up. A great starter K'nex gun would be KILLERK's K'nex gun.

The first step you should do when starting to build is to organize your pieces, so you can easily get to them and so you can see how many you have.

Now that you have all your parts sorted out and ready to go, you can start making the gun.

Let's start with the basic mechanisms of any K'nex gun. All K'nex guns have one thing in common, they use rubber bands or springs (or any other objects that have a lot of potential energy) to push or pull a projectile out of a barrel or off of a track. In most guns, a firing pin or plunger is pulled back and blocked by a "block trigger." A block trigger is a mechanism that blocks the firing when pulled back, thus storing a lot of potential energy in the firing pin. When the trigger is pulled, the projectile is shot out of the barrel or off of the track.

Another kind of firing method uses the same principle, but the firing pin itself is shot out of the barrel or off of the track. This method is most commonly used in crossbow designs, but some K'nex crossbows use string rather than rubber bands and depend on the flexible arms for their power.

Two types of barrels were explained in the last step. There is a third type, the barrel-hopper combo.

A hopper is basically a compartment that holds ammunition until the ammunition is ready to fire, and the hopper will feed it into the barrel. The hopper is called many things-hopper, magazine, clip, etc.-and each one is a slightly different part on a real weapon, however, they are all accepted as the same thing in the world of K'nex.

One example of a good hopper-barrel combination is crestind's AST Rifle.
Another great combo is Ipod Killer's Sniper Rifle.
The best combination is probably the barrel of Perfect Duck's Red Impact because it lacks the friction that most hopper-barrel combinations have.

Most firing pins on the site are a basic rod with a connector on the end, some with tape to reinforce it. Some guns have a similar firing pin, but slide on a track to prevent the firing pin from bending too much and to increase accuracy.

As explained before, crossbows and harpoon guns fire their firing pins rather than a projectile that is hit by a firing pin.

A few new firing pin styles have recently been introduced for semi-automatic weapons. These firing pins are made for semi-automatic guns, and generally do not work for single action guns. Those pins are so new that we have not been able to make a semi-automatic that can live up to the standards of regular single shot guns. Hack124x768's semi auto system can be found here, you can also find mine there as well.

There are a few types of triggers that have been introduced on the site as well. Although some guns don't have triggers, they are probably one of the most important parts of the gun because you can shoot the weapon at a flick of a finger, rather that pulling the firing pin and releasing it over and over again.

The most common type of trigger is called a block trigger. The reason being is that there is some sort of block in front of the pin that prevents the pin from shooting the ammo.

Another type of trigger is a sear system. This system hasn't been used very often, and I think it might be a good idea to use one in one of your guns. The sear system stops the pin from moving in the back of the pin instead of the front. Here is a good example of a gun with this type of trigger.

On just about every gun a true trigger is a must if you want people to like it. I have seen lots of people complain that true triggers are to hard to make, But in retrospect, they are very easy to make after some experience.

The only gun type i have seen that has to use block triggers is machine guns, a firing arm reaches out and pulls all of the block triggers when they are rotated to the top.

There are just about unlimited ways to make true triggers. the easiest way to make a true trigger is like the one on the desert buzzard K'nex gun,
The gun's trigger is a hinge that pulls a orange connector down, out of the way of the firing pin, Thus firing the gun. It is a very simple way to make a true trigger and holds just about the same amount of power as a block trigger.

pic 1: the desert buzzard
pic 2-4: the making of the trigger

The other way is to make a block trigger a true trigger, this is just as easy as making a real true trigger(Once you understand how to make it). there is unlimited ways to make them and you have to fit the trigger to your gun, so i will just add some pictures of them for you to look at and get a feel for making them.

pic 5: the true trigger on my secret project :-)
pic 6-7: the true trigger on the pack sniper
pic 8: mepain's pistol

Before you build your gun, you might want to consider which part of the gun you want to make first. I think it's easier to build the frame first, then the guts.

Think of it this way, If you build the inner mechanisms first, then try and make a frame to go around that, you may need to make some modifications to the inner mechanisms, the gun may not look as good as you originally thought, and it may be uncomfortable to use.

If you make the frame first, you can make it comfortable, make it look good, then make the inner mechanisms to fit the frame. However if you make the mechanism first you can make it work just right but it may look bad and

This process only works well with big guns like the shifle, sniper, and the Inferno. Other basic guns don't even have a frame, they are only naked mechanisms, and all are the same no matter what combination of pieces they are in.

Some tips while you're making your gun

• Be creative, try to make something new
• Try looking at the mechanisms in real guns for some ideas
• Most people are getting sick of block triggers, so unless the rest of the weapon is new, try not to post a gun with a block trigger
• Please don't post a simple "KILLERK copy" gun, as I said before, they are all the same.
• Aside from the overflow of KILLERK copies, try not to copy anyone else's design (e.g. frame design)
• Make sure it has good range. For example, while 10 or 15 feet may be acceptable for a machine gun or semi-automatic gun, it is NOT acceptable for a single shot gun.
• Have fun!

Now that you have a basic understanding of how a K'nex gun works, where to start, what the community wants, and have everything you need, you can start making your unique K'nex weapon!

If you need any help or want me to post anything else in this Instructable, please be sure to comment.

Now that you have something built and you're convinced that it is something well worth sharing, you want to make an Instructable.

Most everything that can be said of making *any* instructable can be said of K'nex gun ones.
- Well explained and as grammatically accurate as possible.
- Clear pictures, multiple views. Enough that, given all the pictures, anyone can easily reproduce. More pictures are never a bad thing.
- Helpful hints at appropriate times so that the person reading can be warned of or avoid any difficulties you may have had. (there are safe ways to pound the rods into all the connectors of a KillerK handle - those kinds of things)

But, for a K'nex gun Instructable, know that not only are you making a complete step-by-step instructional manual of how to build something, but it is targeted toward a specific group. K'nex gunners can be a little picky, particularly because we have seen several instructables--many good, many bad.

The notable K'nex gun Instructables that are well-received and bring the original author respect in the community have some things in common.

- Foremost, they are modest. Even if you built it before you ever saw instructables, do not treat your K'nex gun as a completely original and novel thing for others to envy. Unless after having browsed the site to look for anything to match your creation, do not assume you are the first to have done something. Not looking at other Instructables is not an excuse to claim yours as original. As a community dedicated to innovation, the sharing of credit is a sensitive thing. If you are certain that you have an innovative new feature, then by all means present it. Overconfidence (I.e. naming your gun as 'Ultimate' in the Instructable title) doesn't improve the Instructable any and only gains skepticism and doubt.

- Helpful in the comments sections, and willing to clarify. It's not done once you've made the instructable. Quite often you'll be asked for alternatives for people who lack a certain piece, or you'll get requests for more pictures of a certain step. Don't ignore them. And you can always go back and improve on the Instructable itself.

- Once again, it can't be stressed any further that, unless yours is fundamentally unique or a creative improvement on existing technology, it will be most likely disregarded.

This used to be what I did to make a good looking gun. What you do is lay out the pieces in the general design that you want,. Then you just connect the pieces and fill in the blank space until you get a side panel.

The general idea of laying out pieces in a vague shape can also be useful if you already have the general mechanism, but you just need to figure out how to put it all together. That is what I did when I made mini-gumdrops.

If you are just going to make a side panel five times and connect it, don't post an ible. Also, don't post an ible if you have to ask if you should post it. If you have to ask, it's probably not good enough. 

As K'nex gunners we are dedicated to innovation. At least put some time in to the gun you are making.

Look at my rifle and battle bot. The battle bot works by having the motor pull the ram back and then release it. That took me around 2 weeks to get the system to work OK. 3 days on the hopper and the barrel, and 1-2 days getting max power out of it and perfecting the system. Thats 2 weeks 5 days. and since were on the topic of time:

my rifle = 2 months

the_burrito_master's sniper =4 months.

oodalumps' semi-auto rifle = month or two.

mepains inferno = 9 MONTHS!

This isn't really a step, just a page that shows who all helped out on the project.

Steps 1-4, 6 by, Mepain
Step 7 by, Perfect Duck
Step 8 by, Mykhailo
Edits of steps 2-4 by Loosewire
Steps 5, 9 by, Dsman195276

Special thanks to all who helped out with this instructable!