The F-1 Lego Grenade + Rocket Projectile Launcher

This is the instructable for my grenade/ rocket projectile launcher. The gun shoots my own kind of big projectile (a rocket), but also shoots a knex fragmentation grenade by

Some pros of this launcher are:
-very strong
-can shoot many different projectiles, of different sizes
-accurate(for a grenade launcher)
-range of 25+ feet (depending on what RBs you use)
-the rocket has lots of stopping power
-looks cool

-long reload time (about a minute)
-no magazine (single fire)
-the top moving panel is annoying
-fairly heavy

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The launcher uses a lot of rubber bands (about 10, but depending on the rubber bands, you could have less). The instructions for the rocket is also included.

Step 1: Trigger Holder


Step 2: Underside

This is the underside of the launcher, as well as the underside support for the rubber band holders.

Step 3: Bottom of the Barrel

This is the 'run way' of the rocket. The lengths are: 6x52 (except for the back part with the hole)

Step 4: Trigger Mechanism

This holds the firing rubber band on one end, and the counterweight rubber band holder on the other side.

Step 5: Building the Sides+back

The front may look weird, but just follow the steps.

Step 6: Rubber Band Holders+ Attaching

These hold the rubber bands in place when firing.

Step 7: Putting It All Together

Put together the underside, trigger holder, and barrel.

Step 8: Top Cover+Sight

The top cover is really easy to make, and you can use whatever sight you want if you dont like mine.

Step 9: Underside Rubber Bands

In this step, I used 3 Rubber Bands, but you may have to use more (or less) depending on the strength of your rubber bands. I also used a rubberband to hold the top flat.

Step 10: Attaching the Firing Rubber Bands

I used 6 Rubber Bands- 2 Sets of 3 Rubber Bands. Each set has 3 bands knoted together into a chain.

Step 11: Ammo- Rocket

This is an easy rocket to make for the launcher. To fire, just put it in front of the trigger with the rubber bands loaded. Another alternative is a fragmentation knex grenade which I DID NOT MAKE. Its called the X4 Xploder, by Darth Trainman, which works with this launcher as well. Heres the link to his instructable:



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    12 Discussions


    10 years ago on Introduction

    I love it personally. I made it and found that the rocket actually flies better if you remove the top and the band that holds the top down but you lose the great noise when you fire. 10/10

    1 reply

    10 years ago on Introduction

    Nice Nice NICE!!!!!!!!!!!!! make some more things like a lego sniper or something!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!


    most of it yeah... but the trigger and the sight to use some technic stuff (only a few pieces). Thats why I designed this gun- because I dont really have that much technic and most of the lego guns all use lots of technic.


    10 years ago on Introduction

    The video made me yell at the screen, you got in the way of the camera RIGHT when you fired it!, lol.

    2 replies
    scissorkick master

    10 years ago on Step 8

    good but need to write lengths for the "bottom of barrel" bit. otherwise brilliant.


    10 years ago on Introduction

    EVEn though i dont like legos as much as knex this is pretty kool 4*s