Home > Military, Weapons > Tripod Gun

Tripod Gun

January 20th, 2009 Leave a comment Go to comments

Remote controlled gun, in two versions. Both feature full rotation and a sophisticated positioning system, one features rotated barrel and illuminated fiber optics, and the other features firing mechanism with an ammo clip.


Completion date: 22/09/2008
Power: electric (Power Functions)
Dimensions:  unknown
Weight: unknown
Suspension:  none
Motors: 5 x PF Medium

The basic idea of this construction was a tripod made of three independently controlled linear actuators. It sounds simple, but was quite challenging, since I wanted to be able to control it by moving only one actuator at a time. It was possible only with three actuators, and only with a very specific geometry of the element that connected their tips. The tripod was set on a Hailfire Droid wheel, that served as a base for the rotation mechanism. On the tripod, there was a simple gun with rotated barrel and the fiber optics element powered by a single motor. When I’ve been building this version, I’ve learnt about the firing mechanism developed by the LUGPol user Duku. With his kind permission, I have installed on the tripod a second version of the gun, that looked completely different, but was able to actually fire projectiles.

Despite its simplicity, the gun was able to fire 12 projectiles over a couple of seconds at a range of up to 3 meters. The ammo clip was moved by the gravity, and ejected from the gun when empty. The whole mechanism has later become a subject of my study, with the intent of using it in some military models.


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Media reference:

The Brothers Brick

Categories: Military, Weapons Tags: ,
  1. Boston Abrams
    October 21st, 2015 at 02:08 | #1

    yes, The lego mindstorms ev3 (home)

  2. EV3fan
    November 5th, 2014 at 11:37 | #2

    I took a hard shock absorber out of my Unimog and rebuilt the cannon with that and it fired the rounds up to four metres away whereas the normal ones you used fired them three metres away so using harder shock absorbers does not bring much more speed but slows down the firing rate. And I experienced some problems when firing at a high fire rate-the clip doesnt “fall down” quick enough.
    So shooting the rounds one by one is better and also gives more accuracy.

  3. Sariel
    March 3rd, 2014 at 09:18 | #3

    I think it’s both, actually.

  4. Witherley
    March 3rd, 2014 at 06:32 | #4


    By “official” you’re confusing me as to whether the mechanism’s designed by a LEGO designer, or they made a brand new component. I’m assuming the former.

  5. Sariel
    March 2nd, 2014 at 09:36 | #5

    There already is an official Lego mechanism that can shoot Zamor spheres from a clip. You’ll find it in Mindstorms set, I believe.

  6. Witherley
    March 1st, 2014 at 20:40 | #6

    Could the firing mechanism be easily adapted to shoot zamor spheres? Because being a Bionicle nerd before I got into Technic building I have a plentiful supply.

  7. Sariel
    January 26th, 2013 at 08:47 | #7


  8. Motor
    January 26th, 2013 at 00:42 | #8

    is it posible to make the working gun with the new hard shock absorber?

  9. Sariel
    June 13th, 2012 at 07:49 | #9

    Good luck then, because they are extremely rare and expensive: http://www.bricklink.com/catalogItem.asp?P=x784

  10. June 13th, 2012 at 02:48 | #10

    I am sorry to ask a mundane question about such a nice creation, but what is the number for that wheel that the whole thing is sitting on? I fell in love with http://www.isogawastudio.co.jp/legostudio/modelgallery_model/a047.html and now I have to have them but I cant find it anywhere on bricklink. Thanks!

  11. Touhou
    November 3rd, 2010 at 20:39 | #11
  12. Dan
    October 17th, 2010 at 05:33 | #12

    I believe that what you are talking about is this piece

  13. Brian
    October 15th, 2010 at 19:23 | #13

    I have one ? on the back where the shock connects in between the to right angel 5×3 there is a axle connector to hold the back stiff when shooting what part is that u dont show a good pic of it and i dont see that connector in my parts and then there is a flat under it does that go all the way accross or is it a shory piece hope u can help brian

  14. Sariel
    October 15th, 2010 at 18:37 | #14

    I hope you succeed, it’s not really as complex as it seems.

  15. Brian
    October 15th, 2010 at 18:34 | #15

    ok i see the other pics yeah i will give it a shot thansk so much , i will let u know how it works

  16. Sariel
    October 15th, 2010 at 15:04 | #16

    Everything is clearly shown on photos. If you can’t built it from these, I don’t see how is the instruction going to help you.

  17. Brian
    October 15th, 2010 at 14:41 | #17

    hello i was lookin at ur gun would realy like to see if u could put step by step instructons up so we could see how u built the gun could u do that even if its just the top of the gun the fireing mech u can send them to my e mail even if u could that would be awesome

  18. Sariel
    October 6th, 2010 at 14:39 | #18

    Errr… I did not. These are complete Lego parts.

  19. Alexander
    October 6th, 2010 at 14:13 | #19

    Ok thanks anyway…

  20. Alexander
    October 6th, 2010 at 14:09 | #20

    Hello, great work with all your model’s btw, but how did you design the actuators which control the tilt?? this is causing me all sorts of grief…

  21. Sariel
    August 19th, 2010 at 12:10 | #21

    Well, I can wish you good luck.

  22. sharan
    August 19th, 2010 at 12:06 | #22

    Hi sariel !! I’m thinking of building a radio controlled gun could u help me plzz..

  23. Neil
    August 8th, 2010 at 06:29 | #23

    Sorry, that’s confusing, I mean for all the creations that use the wheel, not the tripod @Neil

  24. Neil
    August 8th, 2010 at 02:59 | #24

    Great design, and the tripod-linear actuator idea can be used for other things too. Maybe you could add “hailfire wheel” to the tags, for all the designs that use it? Thanks 😉

  25. Sariel
    May 17th, 2010 at 22:10 | #25

    Sounds great, could you drop me a link?

  26. charles
    May 17th, 2010 at 21:50 | #26

    i made a fireingmechanism that would do fine on this gun and there is no limit on the clipsize. the only catch is the you have to build the projectiles but it shoots hard, far and accurate. its with pnuematics

  27. Sariel
    April 6th, 2010 at 12:33 | #27

    You’re right, my mistake.

  28. gimba96
    April 6th, 2010 at 11:46 | #28

    gimba96 :in your datatsheet stands that it uses 5 PF xl motors while it is using PF medium motors.

  29. Sariel
    January 26th, 2010 at 14:48 | #29

    There are 14 LEGO sets with this shock absorber, I’m sure you can get some of these: http://peeron.com/inv/parts/2909c01

  30. Ben
    January 26th, 2010 at 14:35 | #30

    Doesn’t seem normal to me, but anyway, what set did you get it with (if it came in a set)?

  31. Sariel
    January 26th, 2010 at 08:11 | #31

    It’s done with a common shock absorber.

  32. Ben
    January 26th, 2010 at 05:42 | #32

    Do you think it would be possible to do this with a common shock absorber?

  33. Victor ruiz
    November 10th, 2009 at 06:31 | #33

    Thanks.By the way it’s cool

  34. Sariel
    November 9th, 2009 at 11:27 | #34

    @Victor ruiz
    Listen, all I have are these photos and I’m sure this mechanism can be built from these. Actually I have rebuilt it myself by looking at these photos. It’s nothing tricky, just look closely at the pics.

  35. Victor ruiz
    November 9th, 2009 at 05:05 | #35

    Victor ruiz :Hey can you give me some tips on the firing mech? all of my mechs mach nothing to yours.by the way wheres the motor to rotate it. i dont know how to put it stable to rotate.THANKS

    how many controls does it uses?

  36. Victor ruiz
    November 9th, 2009 at 05:03 | #36

    Hey can you give me some tips on the firing mech? all of my mechs mach nothing to yours.by the way wheres the motor to rotate it. i dont know how to put it stable to rotate.THANKS

  37. Manne
    August 27th, 2009 at 15:18 | #37

    Yeah, it hacks everthing. From ceramics to lego walls. Test build one yourself, it´s cool.

  38. Sariel
    August 25th, 2009 at 22:28 | #38

    Well, I guess it’s really powerful, isn’t it?

  39. Manne
    August 25th, 2009 at 21:28 | #39

    I used the firing mechanism for a jackhammer. I drive it with 2 xl motors geard up.

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