0.1a - Alpha tech release - Inspired by the Oodalumps chain-gun, the concept of a heavier ammo that used two gear-belts developed. This model, rather bulky, performed the job of firing a single belt of the new ammo and convinced Danny "Stealth Raptor" Ogran to lend parts for a bigger, better model.
1.00 - The K'nexecutioner - Construction went smoothly and without any major problems. Very shortly after its completion and first test-firings, videos were taken. A complete success, it was publicized on YouTube with the video above and various forums to a crowd eager for building instructions.
1.01 - Extensive modifications to the structure were made to allow for a better wheelstand and a foldable third leg. This allows the weapon to be reloaded by a single person.
1.02 - A modification to the gear ratio showed that high torque was not necessary, and the gun is capable of firing faster. This version was chosen to be in-depthly featured on instructables.com.
2.00 -Cyclone- <Declassified>
I'll tell you this now: This model is very difficult and time-consuming to build. Only the serious K'nex gunners need attempt this.
The first ever machine gun built to fire rods of the yellow size! And it capably carries them a good (not great) distance.
The video shows it at an old, very powerful gear ratio. I have since simplified it from the motor having a small->large gear advantage turning the barrels into the motor directly turning the barrels.
40 shots over 10 seconds = 4 per second = 240rpm.
This has been boosted to take a little under 5 seconds, so 500rpm will be my official claim.
Since not everyone uses the same K'nex motors as myself, yours may have to vary and you'll need to be creative. Use this instructible as a reference, rather than follow it completely.
Step 1: Let's Get the Most Boring Part Done First.
You are building 42 single-shot chain link units.
21 are for one side, and 21 are mirror-flipped for the other side.
You can build yours however you want, as long as the red connectors & chain links are exactly where I have them.
I used 8 dark grey connectors per barrel, 8*42=336! Whew.
84 black chain pieces.
84 light-grey connectors.
84 red connectors.
126 silver-grey spacers.
That's just to list a few of what you'll need if you do it exactly my way.
I also reccomend these exact rubber bands. You can get them in the office supplies section of Wal*Mart.
Step 2: The Central Brace and Front Handle.
Step 3: The Front Brace and Wheel-stand
This part is symmetrical, so the pictures only follow one side, through its front and back.
Step 4: Attach Central Brace to Front Brace.
The handle has two rubber bands attached to it. Their pull adds a small amount of comfort in holding the handle, which otherwise remains perfectly vertical when being held.
Step 5: The Dual Motorized Gatling Modules
Both the sides are identical except for their motors, which face opposite ways, and the sections that will later connect the modules to the rest of the structure.
The old ratio is also pictured, if for some reason you want it like how it was in the video.
Hopefully, this movie will help explain the motors.
Step 6: The Structural Cross-member.
(If you haven't noticed by now, I prefer to have my K'nex models built very strong)
I've split the section in two halves for the pictures, so hopefully this isn't too overwhelmingly complex to copy. I don't think it is.
Step 7: The Rear Handle, Third Leg and Motor Control.
If you really have no idea how to set up yours, you can skip this step and deal with it later, once the rest of the K'nexecutioner is built.
Just know that this piece is to be the second handle with which you use to control the motors from and hold the weapon. The entire weight of the K'nexecutioner relies on this piece, so make sure that it is strong and well-mounted.
The third leg is bare minimum - It's not supposed to handle any motion or stress. It's just there to hold the gun while you reload it or leave it by itself.
I really don't know why I took so many pictures...
Step 8: All Parts Unite!
It should be quite apparent how all of the pieces fit together. Make sure that you don't miss anything, make sure all parts are correctly snapped (and not missing if it's obvious a rod should go somewhere)
If you had any confusion about the left/right motorized modules, it's okay. Correct them so it's a perfect fit.
It should, of course, look like it does in the pictures.
Does it seem sturdy to you? I think it looks really silly without the barrels on...
Step 9: Attaching the Ammo Belts.
Be calm, careful, and patient in doing this. I know I had to be. And be ready to try several times.
The ammunition is built to only turn one direction. Be EXTREMELY careful using the motors in reverse! Going backwards, the triggers will catch onto the block that is meant to trip them, and you'll be stuck in a huge mess and probably have to detach the whole belt to repair it.
What you do is slowly feed the belt into the top gears (make sure it's the correct belt), very careful that they do not catch anything on their first way down. Use the motors to turn the belts farther until you're able to hold both its ends.
Eventually, you should have fed the belt 75% of its way through before you're at a good place to lock it all together.
Take off the bottom gun unit (the first one that was fed down), leaving the two red connectors on the black gears. Pull both sides together and link the gears. It should be a very tight fit, and it's quite possible you'll slip and end up detaching the gear-links in other parts and have to remove, repair, and try it all over again.
Re-attach the gun unit and repeat for the other side, then you're all set, unless of course you maybe haven't designed the back motor control yet. Good luck with it, is all I can say. (I'd love to see different versions if any of you guys make them.)
It's hard to attach, but so far, I have not had one belt failure due to regular firing/reloading use.
Step 10: Arming/Reloading.
The best way to reload the K'nexecutioner is to stick it face-down on the floor. It is JUST high enough to allow the ability to stick rods up into each barrel. Nice, huh? The very same rubber bands that power the firing of each barrel also move the triggers into position. They perform this second function rather poorly, but hey, you've got two hands in case they fail. Usually, they don't.
You use the grey connecter/white rod thingy at the front of each barrel to hold each shot in position. It surprises me that this isn't seen in many other K'nex guns...
Fully-loaded, it should have 40 of the barrels armed. I know you made 42 barrels, but!!! Two of them are deep inside and there's really no way around this, unless you want the gun to be twice as long as it is.
You can use blue rods or yellow rods for ammo, but if you try to lock white rods in place with the mechanisms in front, it screws up their trajectory and they fly everywhere but straight.