Surgical Cannon

Introduction: Surgical Cannon

This is the surgical cannon. It is very powerful because it uses surgical tubing instead of rubber bands. I did not measure how far it can shoot, but I think with a small bullet it is pretty far.

Pros of surgical cannon:
Surgical tubing and rubber band never break
Shoots a big bullet for extra power
Will not break if dropped, so very strong
Not too heavy, so is handheld
Has a true trigger
Small and compact
Easy to pull back tubing to load it
Will not break when tubing is pulled back

Cons of surgical cannon:
No stock
Long time it takes to load it
Many pieces required
Surgical tubing costs a lot

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Step 1: Pieces

Gather all these pieces. It takes a lot of pieces to make this cannon, but it is worth it.
Red: 12
Yellow: 5
Blue: 35
White: 32
Green: 123
Dark grey: 27
Light grey: 4
Orange: 20
Red: 11
Green: 4
Yellow: 60
Purple: 34
Blue: 2
White: 5
Nubs: 16
Blue circles: 16
Large wheels: 2
1 medium-sized thin rubber band
41/2 Feet of surgical tubing It Is in the plumbing section of Home Depot
Total Knex Pieces: 408

Step 2: Make the Handle

Pieces needed: yellow rods: 4 white rods: 1 green rods: 2 green connectors: 2 light grey connectors: 2 dark grey connectors: 3

Step 3: Make the Joint

Pieces needed: blue rods: 2 white rods: 5 green rods: 10 dark grey connectors: 1 yellow connectors: 6 white connectors: 4

Step 4: Attach the Handle to the Joint

Attach the handlel's yellow rods to the jointl's white connectors.

Step 5: Make the Central Runway

Pieces needed: red rods: 9 green rods: 24 dark grey connectors: 1 orange connectors: 8 red connectors: 2 yellow connectors: 16

Step 6: Attach the Central Runway to the Joint

Pieces needed: green rods: 2. Attach the 2 green rods to the joints and the central runway's yellow connectors.

Step 7: Make the Lower Runway

Pieces needed: blue rods: 8 white rods: 9 dark grey connectors: 9 red connectors: 2 yellow connectors: 8

Step 8: Attach the Lower Runway to the Upper Runway and the Joint

Pieces needed: green rods: 10
Attach the green rods to the lower runway and the upper runway. Attach the joints blue rods to the lower runways yellow connectors.

Step 9: Make the Wheel Supports

Make 2 of these in mirror images of each other
Pieces needed for both: blue rods: 20 green rods: 20 dark grey connectors: 6 red connectors: 4 yellow connectors: 16 purple connectors: 4 large wheels: 2 blue circles: 4.

Step 10: Attach the Wheel Supports to the Central Runway

Attach the central runway's red rods to the wheel support's connectors.

Step 11: Make the Top Supports

Make 2 of these in mirror images of each other
Pieces needed for both: White rods: 14 green rods: 42 red connectors: 2 green connectors: 2 yellow connectors: 12 purple connectors: 30 blue connectors: 2

Step 12: Attach the Upper Supports to the Wheel Supports

Attach the wheel support's rods to the upper support's connectors.

Step 13: Attach Pieces to the Upper Support

Pieces needed: red rods: 1 blue rods: 1 dark grey connectors: 1 light grey connectors: 1 locks: 2 nubs: 2 blue circles: 4 white rods: 2 orange connectors: 1

Step 14: Make the Surgical Holders

Make 2 of these.
Pieces needed for both: red rods: 2 nubs: 8 blue circles: 8 locks: 2

Step 15: Attach the Surgical Holders to the Wheel Supports and the Upper Supports

Snap the red rods on the surgical holders to the purple connectors on the wheel supports and the upper supports.

Step 16: Make the Leveler

Pieces needed: yellow rods: 1 green rods: 8 orange connectors: 8 red connectors: 1

Step 17: The Leveler to the Joint and the Wheel Support

Snap the leveler's red connector into the joints white rod and the levelers end green rod to the wheel support's grey connector

Step 18: Make the Trigger and Attach It to the Joint

Pieces needed: blue rods: 2 green rods: 1 dark grey connectors: 4 orange connectors: 1 light grey connectors: 1 white connectors: 1 medium rubber bands: 1 white rods: 1

Step 19: Attach the Surgical Tubing

Start by tying it well to one of the surgical holders and then loop it around the wheels. Last, tie it well around the other surgical holder so it is firm, but not too tight.

Step 20: Extras

There should be 6 extra nubs left. 4 of them are for the ammo. Place 2 of the 6 nubs wherever they are needed for support.

Step 21: Ammo

Pieces needed: blue rods: 2 green rods: 4 dark grey connectors: 2 yellow connectors: 2 orange connectors: 2 nubs: 4. there should be no leftover pieces. If there are you missed something. The ammo can be a little different, but this works the best.

Step 22: Loading

To load, simply pull the surgical tubing onto the white connector like so. Then, place the ammo in the runway. Make sure all the orange connectors in the leveler are right up or the ammo will get caught.

Step 23: Firing

To fire, squeeze the trigger.

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    20 Discussions

    Super Shooter

    You loop the bands around where the tubing is tied to. You will have to detach the red rod to do this and then re attach it. It then goes around the wheels like the tubing.


    5 years ago

    Where do you put the rubber bands on if you want them on instead of tubing


    10 years ago on Introduction

     can you use rubber bands?

    Super Shooter
    Super Shooter

    Reply 9 years ago on Introduction

    Rubber bands can be used, but I stopped using them because they kept breaking and then new ones had to be put on. It got annoying.


    10 years ago on Introduction

    Looks pretty darn good! Nice lines, symmetrical (i like symmetrical), and probably imensly powerful! 5 Stars for you!


    10 years ago on Step 18

    Exact same trigger I made.


    Reply 10 years ago on Introduction

    I'm not saying that you took it i just thought it was funny how we both thought of the same thing. I made the trigger before i even saw this gun and this gun was posted before i posted my gun with the trigger. wow this was a lonnnng comment.

    DJ Radio
    DJ Radio

    10 years ago on Introduction

    pretty good, but handle could be better. 4*

    Super Shooter
    Super Shooter

    Reply 10 years ago on Introduction

    Actually if you put one of your hands on the bottom of the middle of the gun, you have better control over it.


    Reply 10 years ago on Introduction

    This is great. Can you please make a video, take some pictures of how far away the ammo lands, or get a rough estimate of the distance it fires? I will be interested to see.

    Super Shooter
    Super Shooter

    Reply 10 years ago on Introduction

    I'm sorry, I can't. I took it apart to make a new cannon and it would take a while to make again.

    Super Shooter
    Super Shooter

    Reply 10 years ago on Introduction

    It says in the instructable in the pieces section. It is in the plumbing isle of Home Depot.


    10 years ago on Introduction

    not bad, and good timing since i just got some surgical tubing.