Wrecktangle Competitor: Instructions and Video

About: I used to build with K'nex. Now I am in the process of joining the United States Army as an 11x.

First, thanks to Instructables for running this awesome contest! It was a lot of fun to put this Instructable together for it, and I hope ya'll enjoy. :D

Hello, here is my first entry into the Rods and Connectors contest. Before start talking about the gun itself, here is the back story.

Back in the mid 2000's, a new fad came into existence: building little toy guns that shoot tiny plastic pieces. Despite sounding a bit odd, K'enx gun building ended up being a lot of fun. As K'nex guns got bigger and better, a problem came up. Most K'nex guns are powered by rubber bands hooked onto a rod. The rod was pulled back, and the trigger would block it. Ammo would be inserted into the gun, and the trigger would be pulled, shooting the rod. This worked great, but if you wanted more the 9 bands or so on the pin, the firing rod would shatter. So, Instructables member
Oodalumps came up with a simple solution, a little piece in the front of the gun to absorb the impact of the pin. The gun with this has been called everything from "Not a Rectangle" to "Untangle."

I built it, and frankly, I had problems. With the gun, I mean.

First, there are no instructions. I had to use the pictures of the gun that are scattered around Instructables. There WERE some instructions on a different site, but that not longer exists. Also, the shock absorber is only useful with lots of bands. Too many to pull back. The worst issue was the shock absorber shattering. The absorber is a ball socket half, and for some builders, it is a rare piece. I destroyed several sockets with gun, and I only have a few now. Anyway, to pull back a bunch of bands, you would have to remove some of the, pull the firing rod back, and hook the bands back on, limiting rate of fire.

The Untangle is generally toted as the best K'nex single shot due its good range. (I never got very good range with it myself, actually.) But with all of its problems, I wanted to replace it. Enter Wrecktangle Competitor.

Did I succeed? That is for you to decide. The first video is of me shooting at a box, and the second is me shooting some yellow rods.


My Competitor shoots very, very far. A yellow rod will shoot 70 feet+, a red connector and white rod (Called "Oodammo", this ammo was invented by Oodalumps, by the way) will shoot 90 feet, probably more with unused #64 bands (I was using five cheap, worn out #64 bands.) and fin ammo will shoot 200 feet+.

My Competitor is very reliable. There is very little that could go wrong. Trust me.

My Competitor looks nice. Not the best looking, but not bad at all.

My Competitor has just the right amount of heft to it.

My Competitor is very comfy.

My Competitor does not need any broken or cut parts.

My Competitor has very nice sights.

My Competitor has a good bullet lock that holds the ammo securely in place.

My Competitor has ammo holders for eight rounds.


The sight radius is not great.

My Competitor is only single shot, but that means better range and reliability.

I would appreciate comments and votes very much.

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Step 1: Parts List.

Green rods: 140

White rods: 35

Blue rods: 10

Yellow rod: 1

Black rods (For pin and guide): 2

Black OR grey rods: 4

Yellow connectors: 71

White connectors: 26

Blue connectors: 2

Green connectors: 5

Red connectors: 13

Grey connectors: 4

Orange connectors: 28

Grey clips: 14

Blue clips: 2

Tan clips: 2

Y clips: 8

Ball socket halves: 3

Hinges: 2

Blue spacers: 13

Silver spacers: 5

#32 bands: 2

#64 bands: 6

#117 band: 1

Step 2: Barrel

Time to build the heavy duty barrel and sights. Have fun. The black rods in this step can be changed out for grey rods.

Step 3: Pin and Pin Guide.

Simple step. Use this pin.

Step 4: Handle

Here is the handle. I think it is very comfortable. There really is not a need for text, as it is rather self explanatory.

Step 5: Stock.

Here is the stock. It is pretty sturdy and does not need a multitude of pieces. You will also be attaching the handle you built in the last step.

Step 6: Putting the Parts Together and the Trigger.

Here you will be putting parts together and adding the trigger and trigger guard.

Step 7: Banding the Pin and Usage.

Just put five bands on the firing rod and one on the charging piece.

Pull the firing rod back until the trigger blocks it, click the ammo into the front of the gun, point it in a safe direction, and pull the trigger.

Have fun! :)

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    51 Discussions


    8 months ago

    THIS is the untangle. I like this version a lot too!

    The Knex Inventor

    3 years ago

    This is definitely the most powerful firing pin gun that I have ever made. Got it to shoot through cardboard from 20ft. away, and with finammo, it achieved ranges of over 100ft!

    2 replies

    Reply 4 years ago

    Tr12? No, this does not have a turret, and it has a different handle, stock, trigger, and barrel.
    This type of barrel tends to look similar to TR barrels. Look closely at the TR8 barrel and this. They are the same type, but different.

    Bottom line: similar barrel but different gun.


    Reply 4 years ago on Introduction

    I see what you mean, and I think it looks better, especially the sight.

    I just wonder whether you got any inspiration from it, I didnt mean copy.

    sonic broom

    4 years ago on Introduction

    I built it and the trigger did not work so I modified it with my new trigger and now it works great! I also took the trigger guard of it was to small. I think i'm going to mod a ton of other things so that it works and feels better but it was pretty cool! Also I tested it one time and the range was great. I want to make some fin ammo to test that out too. I will get a picture up of all the mods when I get the time. By the way how's your slingshot coming along?

    4 replies

    Trigger didn't work?! That was one of the most reliable components for me. It worked very smoothly. What part of it did not work? It might have been the band you put on it was too tight, as it was intended to use a 7 inch band.

    I would love some pictures. :)

    The slingshot is finished, so I need to work on posting it.

    Update I was trying to load a ton of bands on your gun and the pin guide unconnected and the black rod snapped Ouch!! then I got mad and took the gun apart. it was a good gun for the time that i had it even though it killed my black rod. Now I only have 9 black rods left.

    Oh, sorry. How many bands were you using? The pin bending up and snapping seems to be a weakness on tube and stick guns. I have lost several black rods to the TR8.

    You still have more black rods then me. :)

    Yes we need to get a new pin guide system for tube and stick guns.

    I don't remember how many I put on. I have one gun that I have in the works but I put away my KNEX so when I get back into KNEX I should have a gun posted. Also a ton of my KNEX are being used in a binary computer I built off YouTube.