Simple Semi-automatic RBG for TheDunkis





Introduction: Simple Semi-automatic RBG for TheDunkis

About: I used to build K'nex guns. I'd like to think I've grown to be quite good at it, however, I've lost most of my interest in K'nex over my first couple of years in High School, but I do occasionally still come...

here it is...i hope it's clear enough.



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    thanks, took me 10 minutes though, and i only did it because of a request from TheDunkis... RBG isn't really my type, unless it's controlled full-auto, something i've never seen before. i think i have 2 ideas for controlled full-auto RBGs. i might try making them soon.

    Well I think the mech is great.

    Your welcome. It's not very often that I see a mechanism that I've never thought of.

    by the way, this is what i did with my version of the SA 3252 (the trigger mech), only a little different. it is what i said, if you recall, that would be better than the alternating trigger mech, because it's simpler and takes less space.

    You might be right. This looks like it could work for the SA 3252. It all depends on whether or not this requires the (split second) reset time that I talked about with you before. I'm not sure how to explain that any better, but if you understand that concept do you think this mech is reset time free? I might build this to test it out and see if it'll work in a new 3252.

    if i understand correctly, what you meant is that you want it to fire right after pulling the trigger, without having to wait or to release it first.

    if that's what you meant, then you can overcome that by changing the mech a little. what you do is you put only one rod on the pin (instead of 2), so it has to make almost 360 to hit a bullet. then you make the "safety" and "default" arms of the trigger mech adjacent to each other and adjacent to the mag (on top of it). when you pull the trigger, the one pin will do a little less than 360, hitting the bullet on the way, and then reach the "safety" arm and pause until trigger is released, at which point the pin will move just a little bit (from where the "safety" arm blocked it to where the "default" arm is now ready and about to block it), thus eliminating the problem with the reset time, cause you have to release the trigger and pull it again for the gun to shoot anyway (since it's semi-auto).

    in this drawing i made the arms of the trigger mech too far back. you should make them closer to the magazine, giving the pin more distance to go and more speed and strength to achieve. here's the drawing (i hope it's understood):


    i think i was wrong, if what you meant is that the trigger block should be able to pop back up and block before the pin makes a whole turn, then the answer is yes. that's the whole idea behind the 2 arms. one wouldn't have been able to do that, while 2 arms are actually a lot like the alternating trigger mech, only in a simpler, smaller, better way. what i did in my version of the 3252, is even better than on this gun. there, i didn't need a rubber band for the trigger, because after finishing a cycle of almost 180 degrees, the pin would pause on the "safety" arm, and because the "safety" arm was round at the top, once i released the trigger, the pin would just push it back and let the "default" arm go in place. just a fun idea, that eliminates trigger bands.

    It was neither of those things actually. It was almost the second thing you said though; "if what you meant is that the trigger block should be able to pop back up and block before the pin makes a whole turn, then the answer is yes". If you changed that statement to saying; "if what you meant is that the trigger block should be able to pop back up and block before the pin BEGINS to turn, then the answer is yes", that is what I was asking. It needs to be able to block before the pin has even moved so that it cannot slip by when rotating at a high speed. This is due to the fact that the trigger mech only moves as fast as you pull it and the spool will be rotating faster than that in a high powered version of the gun. And if there is even a split second when neither of the blocks are blocking, the pin will go around more than once.

    Thanks for taking the time to work this out with me. So now that I've figured out how to explain it, do you understand what I mean? If so, do you think your mech is reset time free?

    now i'm positive i understand correctly, thanks for explaining. the answer is still yes. the idea of having the two arms is so that the one would be released a little bit after the second starts blocking, meaning that at all times at least one block is blocking. i hope this is the answer you were hoping for, and that you will make yet another version of the 3252 incorporating my mech.

    also, i will soon be publishing a brand new full-auto mech never to be built of knex pretty soon, so check it out once it's there. i hope this project will be as your 3252, that started out as a concept with a lot of potential, only the prototype stunk, and slowly slowly, the idea got shaped and tweaked and remade until it got to what it is today. if you could help me with this project perhaps in a collaboration, i would be most grateful.

    In response to the first paragraph; Awesome. Yes, that's exactly what I need. I have been working on a different gun for the past two months, but when I'm finished with that I'll get back to the 3252. Your mech will be the first thing I try out.

    In response to the second paragraph; I'm not sure if I'll do any building, but I would be very interested in looking at some images of the gun during its construction to have dialogue with you and provide suggestions. I might also design parts of the gun on mlcad on my computer.

    PS: The gun I'm working on is coming out amazing. It uses a tri-alternating trigger system. It's a triple-barreled somewhat semi-auto (cock once, fire 3 times, repeat) with a TR-18 turret. It currently fires yellow rods 50 feet and I'll be working on a pump for it soon. With it's long range and high rate of fire, it will probably be the best knex battle weapon to date.

    i have one thing to say in response to all three paragraphs:

    AWESOME !!!

    also, i am currently working on a semi automatic revolver-like mechanism. it's basically like a revolver piston that is wound back every time the trigger is pulled and released at the end and the trigger is reset without pulling the piston in the other direction. i got it to shoot 3 feet so far, and i'm working on a way to make it shoot further. i'm making this primarily because it's a really nice semi-automatic that, hopefully, will have a good range and already has a high ROF. also, it uses a very small ammount of parts and uses an 8-shot turret.

    Have you seen oodalumps semi-auto? It's on I'm not sure if what you're talking about is similar to that or not.

    aww... man ! it was the same concept. i should thank you though, for referring me to that, cause you have now spared me the awkwardness and hard work of building a unique never-to-be-seen (that's what i thought) concept, posting it and saying so, and only then discovering someone else has already made it. anyway, thanks and i built his gun with an 8-shot turret, which saved me a lot of space and parts, and it now works great.

    Ahh, it was? Oh, well. There's a similar one on instructables too. I can't remember who made it though.

    Loosewire, SOE operative

    Ok, good luck if you do so =D

    cool mech. can you use this for bigger bands too?