A Gas-Engine Slingshot

Discussion in 'New project ideas' started by WildBill, Nov 5, 2013.

  1. WildBill

    WildBill The Silly Song Guy

    I had a lot of driving time at work today and I began to think of how I could turn an old motorcycle into a self-cocking, repeating slingshot. Below is a very simplified drawing of what I came up with- I might make this into a project for next summer.

    A. The motor and transmission from a small motorcycle. This would be attached to a frame (not drawn) that would also support the rest of the contraption. The whole thing could be put on a swivel-turret one the balance points are known.

    B. The flywheel. I would take the rear wheel of the bike, remove the tire and add a large ring-gear below the rim. Where the tire was I would add weight (lead or steel) to allow some kinetic energy so 'shifting gears' for higher firing rates wouldn't stop the whole thing from working.

    C. The Cocking chain. Attached to the frame by 4 gears, this would actually cock the slingshot.

    D. Cocking chain gears. 4 of them so that the bands would have time to fully release before the next cocking and firing.

    E. Cocking Pull. Attached to the cocking chain, two pulls, equidistantly placed would cock the weapon.

    F. Barrel. Made of steel, the 'pouch' would be fixed to the barrel via ball bearings into slots on each side of it.

    G. Magazine. Balls would be loaded mechanically into the 'pouch' before firing. Since the pouch itself wouldn't be closed during cocking, this can be done near the end of the cocking process.

    H. Handlebars. Taken from the motorcycle, they would have the motor, transmission (via cable) and flywheel brake controls.

    The shingshot would fire each time a pull dropped below the cocking chain gear directly below the magazine. In theory, it should be able to fire repeatedly until the bands simply broke from overheating. So, what do y'all think? Is the idea possibly doable or are there too many inherent flaws in the concept?

    -Wild Bill

    Attached Files:

  2. BeMahoney

    BeMahoney Builder of things

    vibration; natural frequencies

    Hey WILD one,

    I personally think that chain would need a whole lot of guidance
    or thinking in advance/ mechanisms to handle vibrations of the
    chain-powered systems..

    But YES, this can be done (maybe with an old chainsaw to start from?)


  3. WildBill

    WildBill The Silly Song Guy

    Agreed- two idler pulleys would be needed to maintain proper tension- if not a chain-rail on the top pull length. Also, a 'derailleur' mechanism for additional stabilization along the draw chain for the rest of it's travel. Other things would be needed like a quick-disconnect from the chain draw to the barrel, and some thought to make a gear or cam driven loading mechanism to avoid jamming or double-loading.

    -Wild Bill
  4. FIAAO

    FIAAO Failureisalwaysanoption

    Something like this?

  5. WildBill

    WildBill The Silly Song Guy

    Yes, very similar- just with a LOT more power.

    -Wild Bill
  6. Brazilviking

    Brazilviking Thread Hijacker

    I think it is possible....and by having this idea I think that you are crazy. But who isn't?:D
  7. rock slinger

    rock slinger I rarely shoot rocks!

    Definetely possible give it a go
  8. Flipgun

    Flipgun Well-Known Member

    The easiest thing for the flywheel may be to leave the tire on the rim, cut a hole in it fill it with sand or concrete and reseal.
  9. Withak

    Withak aka Whitehawk!

    Looks like a fun project. I'm just going to stand back here in Oregon while you fire it up, just to be safe :)
  10. Slagskimmer Mike

    Slagskimmer Mike thinks TBG smells better than roses

    Finally, a slingshot that makes smoke and noise!

    It should be done. I'm liking the way the big guy designed his full-auto pencil shooter more than the long chain idea, though.
    Having the band-puller lugs on the flywheel itself is just sooo elegant.

    I hope this gets built in any form--it'll be a first!