NOW WITH VIDEO: Slingshot Minigun goes big!

Discussion in 'Show off your homemades!' started by JoergS, Oct 23, 2013.

  1. JoergS

    JoergS Administrator

    5,803
    115
    63
    Don't know about that. There will be some deviation, but the question is how much. The bolt will stay in the barrel for approximately one tenth of a second after the trigger has been pulled. If I turn that crank very fast, I might get one turn per second.Effective diameter is 25cm, circumference is 78,5 cm. Therefore the bolt will have travelled 7,85cm counter clock wise on its 2 meter long way through the barrel.

    That counter clockwise turning will continue after the bolt has left the muzzle, but then again the bolt has a lot of air resistance sideways, and not very much in flight direction. So the air will reduce the turning effect.

    My former gatling gun designs and also the minigun did not show a negative effect - and the minigun turned much quicker than one turn per second!

    We shall find out.
     
  2. Withak

    Withak aka Whitehawk!

    4,700
    2
    38
    That's just a really cool creation Joerg. Nice work.
     

  3. JoergS

    JoergS Administrator

    5,803
    115
    63
    Have now finished all five barrels. That was a boatload of work.

    8,5 meters of TBG full width on this monster...

    It works! Will test it some more tomorrow, and make an "appetizer" vid.

    [​IMG]

    [​IMG]

    [​IMG]

    Here you can see the "automatic piano" triggers:

    [​IMG]

    [​IMG]
     
  4. JoergS

    JoergS Administrator

    5,803
    115
    63
    [ame]http://www.youtube.com/watch?v=OWetjmi01XQ[/ame]
     
  5. Withak

    Withak aka Whitehawk!

    4,700
    2
    38
    Nice to finally see that bad boy in action! Great design, very high coolness factor :cool: It will be very interesting to see the SOG tipped bolts in the next video.
     
  6. xXdoomXx

    xXdoomXx Junior threadjacker ag. J

    1,417
    0
    0
  7. Antraxx

    Antraxx #7

    855
    1
    18
    That Baby needs to be painted red and mounted on the Back of your cute little Pickup^^
     
  8. JoergS

    JoergS Administrator

    5,803
    115
    63
    I currently think I should mount it on my trailer - all the carriage I need!
     
  9. JohnKrakatoa

    JohnKrakatoa Loudest boom on Earth

    1,287
    0
    36
    This
    is
    wondeeerfuuul:eek::rolleyes:
    Hi Jörg cold you please upload some detail pictures of the loop that attaches the bands in the front when loading? I wanna see how you attached the loops to TBG and what they are made of because It can be a good technique for attaching bands to forks of a very thin armed SS without bulky ends (like mine SSStake).

    Also, how did you encase or attach the nails into the stakes? Curious.
     
    Last edited: Oct 27, 2013
  10. JoergS

    JoergS Administrator

    5,803
    115
    63
    I just used the constriction knot to tie the bands to the loops.

    Used a hand drill exactly the size of the nails (8mm) and hammered the nails in, very simple.
     
  11. Cadman

    Cadman New Member

    74
    2
    0
    With a 6-minute load time, does the first set of band loose strength?
    Also, could you offset your trigger to the right, and make the bolts fire at the top of the rotation?

    Brian
     
  12. JohnKrakatoa

    JohnKrakatoa Loudest boom on Earth

    1,287
    0
    36
    OFC and then sharpened the other end..I am stupid :D Ty.
    Nice! so now I have at least 5 "new" ways to attach bands to really thin forks. If only I could CAD or draw I would post them right away haha
     
  13. BeMahoney

    BeMahoney Builder of things

    6,101
    7
    38
    Zentripetalkraft?

    Pardon me, but the above is not likely to happen. Without any active
    centripetal force the bolt would not spiral around the axis of the gun;
    The bolt would just keep its velocity sideways; meaning that if the barrels
    are turning one round per second, then every two tenths of a second a new
    barrel is fired. And so 72° divided by two; 36° "offset" would appear.

    Without having seen the vid i bet the bolts travel to the left (maybe 19:30h) when turned counter clockwise..
    on the clock?!)- a heavy bolt is not that heavily affected by aerodynamics-

    just my bet..

    Greetings,

    Be
     
    Last edited: Oct 27, 2013
  14. JoergS

    JoergS Administrator

    5,803
    115
    63
    Seems like in real life, once on their way the bolts fly very straight. It took me 0,6 seconds to fire all five shots by the way.

    Brian, the loss due to the cooling is easily compensated by more rubber, at least as long as it isn't very cold outside.

    Yes, the release could be moved to the right until the bolts exit on the top position - but why? You can easily compensate by aiming a bit higher. As long as the shift is reproducible, no problem.
     
  15. Will

    Will Thread Hijacker

    3,375
    2
    0
    Great work Joerg! It is probably a good thing that I do not have one of these. I could see myself missing a lot of work because I was too busy shooting things!
     
  16. xXdoomXx

    xXdoomXx Junior threadjacker ag. J

    1,417
    0
    0
    Rubber is just like batteries I had an rc car that had 15 minutes in 20 degrees and then I used it in the snow and I only had half maybe even less.....

    Bv translator: rc= remote controlled :D

    J
     
  17. JoergS

    JoergS Administrator

    5,803
    115
    63
    Have now made five "bolts" from the SOG spirit knives...

    Did you notice that they even put my logo on the blades? :)

    The enemy is already in place... video tomorrow.

    [​IMG]

    [​IMG]

    [​IMG]
     
  18. Withak

    Withak aka Whitehawk!

    4,700
    2
    38
    Can't wait for this one...

    The bolts look awesome :cool:
     
  19. JohnKrakatoa

    JohnKrakatoa Loudest boom on Earth

    1,287
    0
    36
    The Sog Spirit looks really good. Prettyy bolts :D