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NEW!!! FULL AUTO PIN!!! OUT OF KNEX?! Answered

hi there!
Dr Richtofen and i where just talking
and we where talking about full auto knex
so i showed him my old idea
we talked
and we are near a prototype!
we are still drawing and stuff
but, we are near it!
stay tuned for more!!!!
we will keep the prototyp secret, so no one can steal it!

now(yes i know, on a forum pro's and cons? haha!)

pro's
it will be FULL AUTO!!!! so no more anoying pull, fire, pull fire, just one pull back for 1 mag!(if we succeed!)
it will be the first one
i mean, FULL AUTO!
it will add more realism to the guns!
you will never have to reload slow again!

cons
it's a prototyp
the power will be slowly killed...
we didn't figer out how to make it work
we need to find a good gun for it

Discussions

Please forgive me if this comes off as spam, but I truly think that the most feasible sort of full auto will come from the type of mechanism utilized in this gun.  There is an argument as to whether you could actually call it fully automatic, but it is the closest thing I thing we can get and still have a decent amount of power behind every shot.   But then again I don't know quite how your mechanism works.  Just know that efficiency is going to be your main goal here, because you don't have a lot of stored energy to work with.  If you want, try building upon the mechanism seen in the gun linked above.  I think it has the potential to shoot upwards of 40 feet if ratios can be optimized and friction can be minimized.  

Hey bro, I had no idea you were still around. Its kinda funny that this is the topic you would drop into.

I lurk here and there lol. I'm not very active but I just thought I'd give my two cents on this forum, seeing that full auto is a very unexplored (and rightfully so) area of K'nex guns.

Ah, I see. Well, it is really good to see you posting comments again. I don't think we can expect any more builds from you???

Yeah, the full auto pin concept seems almost impossible, but then again, so did bullpup guns back in the day.

Sorry for the very delayed comment.

But think of all the energy that is wasted stopping and then resetting the pin. It it only needed resetting, it would be plausible, but the energy that resets comes from the energy of stopping it (at least in this case), and so as long as the pin is in contact with something that stores energy, energy is going to be lost rather quickly, because for every joule of energy going into storage, you lose half a joule.

I think the best bet for full (and semi) autos comes from exterior power sources that match up each power source with each individual shot. For example, I came up with this design a while back, but it may not be doable with K'nex as it will require some very precise placements:

Imagine a turret connected to a rod that runs through the upper body of the gun, and this rod is connected to two rubber wheels (or 3 or 4, it doesn't matter). Now, right below these wheels rest a vertical magazine of cartridges, preferably made up simply of a lot of gray connectors, a red rod(I think that would be the best length, but maybe yellow), a block trigger, and a pin with a rubber band. The cartridge that is in contact with the wheel is lined up with the next turret shot. The manual trigger is simply a device that comes down on the block trigger of the ready-to-fire cartridge. So when the cartridge goes off, the bullet fires, allowing the turret to rotate. Keep in mind that the now-empty shell is in direct contact with the wheel that is attached to the turret. So as the wheel rotates, it ejects the shell, the magazine pusher will push the next cartridge into place, and so long as the trigger remains pulled, the pusher will push the cartridge's block trigger right into the manual trigger mechanism, setting the next cartridge off. This will continue until the trigger is released, at which point the chain reaction must stop because the block trigger cannot be set off.

Hopefully that was detailed enough for you to visualize, but I think the look and feel and effect of that gun would be so amazing. But to answer your question, I probably will not be building any more K'nex guns, although I am almost done with designs for a wooden crossbow pistol, which would be pretty amazing. I would like to post the KSP. Even though it isn't 100% reliable, I still love it, and I think others would too.

I'm pretty sure that you need a motor to make the pin go back and forth repeatedly. for a semi auto mech, no motor is required (just saying).

I don't think you understand how physically impossible this is.

Anf i think you don`t understand that every fisical law can be broke.

No physical law can be broke. That's why they're laws.

then you don't know how much i tried and tried untill i acomplish my stuff

The first idea(mine) was to use 2 springs, they would make the pin move, but thr energy got lost to fast, i now havr another idea i saw on youtube with a.wooden rbg

Let's sum this up. K'nex uses stored kinetic energy because we're not ever going to invest in chemical, nuclear, or electric energy. Where does it come from? Well, we focus our own physical labor into a controlled mechanical force like rubber bands. That said, we are the source of power for K'nex guns, all the guns do is store the energy. So, the only way you can make a gun that fires automatically without multiple storages of energy is to have one constant storage that uses only a fraction of the energy for each shot. But these are just too finicky for reasons you've already mentioned plus the unreliability. For example, you could wrap a band around a hammer that spins around and around with each trigger pull. Another crazy idea would be to wrap a long, stretchy band around and around a long base and make a slingshot that would reuse the band each time it came around and reset. There just aren't many feasible ways to make a good full auto without the use of many bands.

true. I've seen slingshots, semi auto's and every other mechanism, except a full auto pin gun. It's practically impossible to make a full auto pi weapon, without a motor or some other power source.

It doesnt use rubber bands to power te pin, as soon as i get the things i need i will start working on a prototyp

Here is my guess: You have a pin that is banded from both ends, so that when it goes forward, it bounces back.

I'm just guessing because new builders been bringing up this idea since the beginning of knex guns.

A wind up mechanism. Just as bad. This won't work.

That was his first idea, already told him it will lose way to much power. IMO, this topic was made way too soon, and I don't think we'll succeed

1. It's prototype

2. Unless you are using a separate pin for each shot, there is no way this gun will shoot any distance worth anything

3. You didn't figure out how to make it work. Basically everyone can come up with a cool idea. Making it work is the hard part.

There is no way to make even a semi powerful full auto knex gun without using multiple pins or a rubber band slingshot method. This won't work out.

We don't know anything yet bro dont jump to conclusions!!

There is no way you can make the pin pull back and shoot forward by itself without having it incredibly weak. People have though about how to do full autos for quite a while now.

I said that in our conversation, that an automatic pin would be incredibly weak.

yes indeed
it would lose it's power over time, and the mag ammo it could shoot is i guess 5 rounds with the present model