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Your K'nex Concepts - Share your ideas here! Answered

Post your own knex invention ideas here. Include pictures as well as an explanation. If I like your idea, I will put it on my K'nex Concepts instructable crediting you with the design.


What about a full auto arrow shooter. Heres how it will work, You will turn a crank turning an internal mechanism releasing an arrow every time you turn the crank

I've had this idea for a while, but I was visitting lkmachines, and I found a gun that had an idea similar to mine.

An RBG, with a detachable mag. The magazine holds rubberbands, not actual pieces.
So think of having a handle, with a detachable top part of the gun.
Again, I have a picture of what I mean, but it doesn't want to be in the comment.

 A truly sub-machine gun out of knex.  It would work by having a large magazine, but instead of holding individual shots, it would hold barrels with a block trigger.
 and if you pull the trigger you release the magazine releases until you let go of the trigger, then the mag is blocked and it wont fire. a downside is that you have barrels littering the area.


Pretty much all chain fed guns are like that, they just have a chain, not a mag.
I think DJ Radio made one that was semi auto.

I don't know if this has been tried before, but I thought it was interesting. I was inspired by an article about dual-stroke revolvers.

Kex gun concept.bmp

Extreme Builder was the first. Search for his truely semi auto gun.

 Would any of you like me to post instructions for a knex transmission? Three speed+ reverse? I am developing a fully- automatic transmission for a rock crawler.

 An idea for a powerful full auto came to mind when, oddly, I was looking at lego engines on youtube. One of these engines:www.youtube.com/watch. The system they use is called a 'scotch yoke'. It sounds like an egg, but is a way of transfering power to the crankshaft from the cylinders see animationwww.youtube.com/watch. the slider can be used to pull back a ram rod and let go. The scotch yoke increases torque, so even the normal knex motors wouldn't struggle

Very nice, I've tried something similar, but it was a lot more complicated. I'll add that to Knex Concepts sometime.

 I might attempt at using this system to make a slingshot automatic

Take a look at my weight powered full auto on the step "Concepts In Progress" on Knex Concepts.

 Another idea is a knex ball shooting gun. I made a spiral knex lift, then when the motor span fast, the tower toppled over, firing the ball out of the top. With development, this might work! A knex ball shoota!

 so did i but it's not like im ever going to fo it though... so i dont really care, lol :P

 You could try using the rotational force from a power drill and converting it to directional force and make a grey rod move back and forth uber fast.  That grey rod would be the ramrod and using this, if you attached a mag to it, it could possibly shoot full auto.  the only problem is that from the ramrod moving so fast so such, it could melt and potentially catch fire..

I have an idea.

M203 Grenade Launcher. Ram-action, blocked behind the ram, like on Sgt. Licorice (Or was it Major Johnson? o.o). I think I could pull it off, but I'm not sure.


8 years ago

i made a dual revolving pistol! ill post a forum later....


8 years ago

Someone should come up with an idea of a true k'nex rifle that causes plain rods to spin.

 well instead of trying to put spin in the barrel i found out how to put the spin in the rods (i think)

well when i was playing around with one of my engines my cam shaft  broke of course causing the engine to lock up but for a split second the drill still went when i pulled the drill off i found that the lines to attach things to was twisted but the rod was still straight it didn't even come into my mind what i had done but then when i shot it yesterday (i heard people were trying to put spin on stuff) that for some reason (i guess cause of the spin) it flew further that the other similar rods of same length even color i don't know how to prove it but i think its cause of spin

I didn't quite understand that. Can you please explain that more clearly or draw something?

O wow, so you twisted the rod. How did you do that? I know that you said something about a drill and an engine, but I didn't understand.

 when the engine locked up (not being able to move) so did the rod but the drill was sooooo tight that it twisted the out side of the rod

Okay, so as I understand it, you turned on a power drill with one side of a gray rod inserted into the drill and turned on a motor with the other side of the gray rod inserted into it, is that correct?

Already done, go check it out, it's on the new step 11.

I think I just had a random epiphany that might work.
Prolly wont, but still, You never know.
I'm scared.

I read your comment, and think I just thought of something.

I tried making a basic concept drawing in paint, and I realized that it wouldnt work.
It was for Oodammo.
I thought it would work, until I actually thought about it.

I have a random idea for a drum mag.
basically, it is 2 large yellow wheels and a chain around them.
and on the chain, is a turret that fits into the barrel.
Random, yes.
Possible, maybe.
I don't have any of the large yellow wheels, so I can't try it.
Or maybe it could just be a TR8-36 turret. It should work just as well.
I just don't know how you would be able to have the mag/turret stay in place.

I'm not sure what you mean by "on the chain is a turret that fits into the barrel". Can you please explain that more clearly or draw something?

Basically, a detachable turret.

I don't really know how explain the new concept of a turret, but it prolly wouldn't work. So this part in unimportant.

But we already have drum magazines. They just aren't detachable yet.
The TR8/18/36.
Just imagine having one of those, but with a detachable turret.

It would kinda be a drum mag...

Ah, yes, I posted an idea for a detachable drum mag weeks ago on Knex Concepts, so I know what you are trying to do now. It's concept 6G4, in case you want to look at it.

Yeah, exactly.
I'd try it, but I'm low on pieces.

I have a basic idea for it I made in paint.
My picture doesn't want to be posted, so I'll send you the pic in a PM.

Just realized you can't put pics in a PM.
I'll try to put the pics in my account.
So just click my name above, and then look for a pic I made in paint underneath my avatar picture in the top left corner.

I suggest that you learn how to explain things better. Revise your writing as you type and imagine yourself as someone else reading what you are writing, someone who doesn't know the information that you are communicating. And use your best english.

 when you put rifling the barrel on the instructable instead rifle the bullet

as a knex ball machine diesiener i have come across a coll looking element that takes 10 BALLS to make it work its so cool but it takes about two feet of space i know u think im joking BUT IM NOT.