"Mantis" Slotbow - why did I not think of this before?

Discussion in 'Show off your homemades!' started by JoergS, Jul 11, 2015.

  1. JoergS

    JoergS Administrator

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    The prototypes for potential new commercially made slingbows got me thinking...

    Whisker biscuits work but they are expensive. Plus they don't last long, because of the rubber bands following through, damaging the bristles.

    Rings will hold, but they are not accurate at all.

    Therefore I tested a new concept today... so easy it is ridiculous! Just a hole for the shaft and some slots, 120 degrees, for the vanes...

    It works! Super clean release, shot after shot after shot. NO follow up problem.

    The weapon is a prototype, I used some leftover wood from the firewood pile... very gnarly. I like the look, and who knows I may apply a nice finish soon.

    Video is filmed, will now do the editing.
     

    Attached Files:

  2. TheDaddy187

    TheDaddy187 Administrator

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    i must get some arrows and make a slingbow at some point
     

  3. tomfreds66

    tomfreds66 Member

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    I like it.
    Is much flaring needed to smooth the entry of the arrow into the rest?
    Might work for a railless minimalistic crossbow too ........
     
  4. bigdh2000

    bigdh2000 Administrator

    Nice concept but what happens if the arrow is twisted wrong and the tail feathers do not line up with the gap? Hopefully the video addresses this question.
     
  5. Jack739

    Jack739 Gun-'Slinger'

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    Hey Dan, i have the opinion that the nock on the arrow will guide it, while drawing and releasing, so it
    wont happen too often that the tail feathers get ripped off haha!

    I really like the concept Joerg, i have some crossbow arrows here... maybe i build one for Phun! :D
     
  6. JoergS

    JoergS Administrator

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    I applied a little bit of flaring, but indeed the nock aligns the arrow quite nicely... the hispeed cam clearly shows that. Also, the vanes look pristine even after dozens of shots.

    I really recommend this! Much better than a whisker biscuit, and zero cost.
     
  7. Bone

    Bone Slingshot Shooters

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    Painted lines along the shaft of the arrow would make sure the fletching is lined up.
     
  8. deraNdy

    deraNdy Active Member

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    Great great and again great....is the hole in the middle some kind of tapered? I can remember these slot on a crossbow of you. Seems you got the Concept for this before ,without knowing. i like it a Lot....
     
  9. JoergS

    JoergS Administrator

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    It is not tapered, but flared out a bit at the "shooter" side, to ease the vanes down the slots... used the dremel for the job.
     
  10. deraNdy

    deraNdy Active Member

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    Ok thanks. And is there any negativ thing about the bandset slapping on the plywoodstarguide?
     
  11. BeMahoney

    BeMahoney Builder of things

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  12. bigdh2000

    bigdh2000 Administrator

    Sorry, I should have been more clear. Do not get me wrong, the idea is simple and profound. However...

    True, it works fine for those that set the nock the same way every time. However, if the eventual intent is mass production, you must account for the person that likes to line up the nock flipped 180 degrees.

    Perhaps a design that allows both directions? Six slots in lieu of three.

    Also, there are times when I twist the "pouch" to make the arrow do fun things. This design does not allow for this.
     
  13. JoergS

    JoergS Administrator

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    [ame]https://www.youtube.com/watch?v=Y41dwLSjlwE[/ame]
     
  14. resortera

    resortera Senior Member

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    You cam make the center spin whit the bands like whit a bearing sryle or somthimg i dont know if you catch me
     
  15. dinobuddy

    dinobuddy Senior Member

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    I think all you need is for the slots to be wide on the shooter side, and very narrow on the target side. As the arrow enters the slots, they will "funnel" the fletching.

    Also, anyone else immediately think of Battlestar Galactica as soon as Jörg reveals the slots?

    https://youtu.be/wa7zDfGVh74
     
  16. Kresimir

    Kresimir New Member

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    I find it very surprising and fascinating that the slot does not damage the vanes (fletching) of the arrow! Very interesting stuff!
     
  17. resortera

    resortera Senior Member

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    Talkint about somthing like the pik make the center spin make the arrow spin anyways after seeing the video it seems to be just perfect like it is

    [​IMG]
     
  18. calinb

    calinb New Member

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    Very cool, Jörg! Thanks for disclosing it to the public so we can all work to improve upon your idea, instead of being paralyzed by someone's patent claim! (At least I hope no prior art claims exist.) Even though I only have your Rambone mesh model to work-with and no solid model, I'll try to CAD-up something similar to the Mantis myself and "boolean glue" it to a Rambone handle using the Blender software program (and thanks for the Rambone too).

    BTW, I 3D-printed a Rambone in Taulman 618 nylon and took my first fork with it while trying to shoot a 53 cal. lead ball at 20 fpe. (My butterfly technique needs work.) When printed optimally, 618 is very impact resistant. I could hardly even find the mark (at least I think I found it..maybe). I quit testing it after I hung 150 lbs. from the forks.
     
  19. bigdh2000

    bigdh2000 Administrator

    That's awesome. I have seen 3D printers spit out all kinds of things but have only seen it do a slingshot online. It must be a treat to not only see it printed but then test it as well. 150 lbs is crazy.

    Perhaps you can use the printer to make a part that allows shooting with the arrow inserted either way.
     
  20. Diaboloslinger

    Diaboloslinger New Member

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    Dammit! I'll have to return my recently acquired whisker biscuit....