This is my knex switchblade. It was inspired by J_SCAP's butterfly knife. I decided I would make a switchblade, so it would lock in the open position or lock in the closed position (well, sort of), as the video shows (I hope you can view it). Hope you enjoy! Post pictures or videos if you build it!

This can also be used for self defense training if you add some of your sister's lipstick to the edges, that way you know if you have been cut and if it was a puncture or a slash. Although if you have the money, you should probably buy an actual rubber knife.


NOTICE: Yes, you can make a comment that actually has nothing in it. Just because Mepain and I did it two years ago does not mean you can spam up my instructable.
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Step 1: Materials

Picture of Materials
This is all you will need. Exactly. I know this because I took apart the knife and rebuilt it from memory.

Step 2: The Frame

Picture of The Frame
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zzzzzzzzzzz 049.jpg
zzzzzzzzzzz 050.jpg
This will become the frame of the knife.

Picture 1: Build these.
Picture 2: Mutila... I mean "Enhance" a grey connector.
Picture 3: Attach it here.
Picture 4: Attach a red connector here.

Save the other part of the frame for the next step.

Step 3: The Blade

Picture of The Blade
zzzzzzzzzzz 052.jpg
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This is the blade very simple.

Picture 1: Build.
Picture 2: Attach it here.
Picture 3: Attach the other half or the frame.

Now you will need a rubber band for the next step.

Step 4: Bands

Picture of Bands
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za 002.jpg
za 001.jpg
Attach a rubber band as shown in the pictures. The "improved" version (last three pics) can flip open much easier, but can't be flipped closed. I like flippy stuff. I have flippy pens, combs, knives, knex knives, pocket knives, and more!
morrisme1 year ago

cool. 4*.

It's fine if u have no bendys. I feel your pain. There are many knex pieces I never heard of!
w8.. does it lock down in place by its own
ashchetm5 years ago
I built this knife a while ago, but pulled it outta a toy pile today, I modded it to have a switch, works great, would recommend it to anyone considering making this knife.
Whaleman (author)  ashchetm5 years ago
Very nice. Good job.
Thanks! It wasn't hard, I just thought it would be nice to open it easier.
Whaleman (author)  ashchetm5 years ago
Yeah. The problem when I was designing it was that I was trying to have an auto-opening style blade instead of an assisted-opening blade. Now I can see that assisted opening is better.
Yay for community help! POWER TO THE PEOPLE!!!!
stopanator5 years ago
sorry hailo said that darth acexxacer to tell him kinda what it means you where abiut so say mutalate but said enhanced...
Whaleman (author)  stopanator5 years ago
No, seriously. I can't tell what you are saying. Use some punctuation, use some spell check, and actually spell out my name. It's not that hard, stopanator.
stopanator5 years ago
when he says multila i mean enhance cuz mutilated
Whaleman (author)  stopanator5 years ago
What does that even mean?
stopanator5 years ago
nice one
NYPA5 years ago
i wouldn't mod a piece for a K'NEX knife.
Whaleman (author)  NYPA5 years ago
You don't have to. You can just use part of a ball joint connector. But if you've been knexing for awhile, you probably already have a few half pieces.
Whaleman (author)  Whaleman5 years ago
'Mykhailo (author) says: Oct 30, 2007. 9:18 PM it stops the "blade" from coming too far out, but a ball joint connector will work too. '
crestind7 years ago
(removed by author or community request)
Whaleman (author)  crestind7 years ago
Ima cutyu up wit my combat knife... VVhat now! (wit a Deutsch accent)
gotja Whaleman7 years ago
u kno wat ill just shoot yall with my bereta
Whaleman (author)  gotja7 years ago
Dammit! I guess I will just have to go get my Browning M2HB .50 cal. I hete usin it, the bullets are so expensive!
up close, sawed off, double barreled 12 gage shot gun mwahahahaha!!!
Whaleman (author)  the gizmoman7 years ago
Jackhammer Mk3A1
jollex Whaleman6 years ago
oh no,here comes my cobra attack helo with mounted 50. cal miniguns(not even real) and 10 auto loading gernade launchers.
ill shoot your cobra down with the scorpion tank(from halo)Mwahahahahahahahahah
ill just send master cheif over for a little visit,case closed!!!!!!!!!1
last time i heard master chief is still fighting to save the earth in halo3 so he wouldnt have time to come to your aid
Nope, I BEAT IT. do you play half-life?????? I need a buddy so i don't get pwned.
i beat it about 2 weeks ago(halo) sorry but i dont have half life i still cant believe that they killed off the master chief
strange i did not like halo2 and 3. half-life and half-life 2 are fun.
I'll blow the tank up with a rocket launcher. What Now!?!?!?!
you still have to get past my MG and rockets first
*snorts* You can't shoot what you can't see. Anyway, I'll just run up to you and beat you out of it.
all i have to do is position the tank to where you have to come out in the open to get the shot and a rocket leaves a trail of smoke
You ever heard of the hit and run technique? Anyway, What good would blowing it up do? I'll just beat you out of it, stick you and run away and get back in the tank after you've died.
Whaleman (author)  knex hater hater7 years ago
Don't make me take out my A-10! Or should I use an ICBM? Your choice.
ok,you lost me you.
Whaleman (author)  knex hater hater7 years ago
Ha! You have nothing better than a Jet fighter, with 30mm Gatling gun and sidewinder missiles, and a Inter-Continental Ballistic Missile! I will now consider your unconditional surrender.
ill ask the emperor if i can borrow his death star for a little while (oops there goes the planet)
Whaleman (author)  the gizmoman7 years ago
Sorry, I already have my own personal Death StarTM
then ill blast you away with dark helmets spaceball one star ship at ludicrous speed
Oh yeah?*aims jar of rasberry jelly at ship* You'll lose the bleeps, the creeps, and the sweeps.

Now I shall go get the mega-maid and suck all the air from your deathstar. Mwahahahahahahahahahahahahahahahahahahahah.
the spaceball one is the megamaid stupid and as i recal vogons werent smart enough to steal the winnebago anyway
Duh. I knew it I'm surrounded by ***holes. I know the Mega-
1 the winnebago is the only ship w/the rader jamer thing 2 vogons is in your title so i asumed you were one (i forgot you woudnt need to steal the maga maid/spaceball one anyway ,your vogon ships are planet distroyers any way)
Yep my vogon ship is. That means that I won's have much trouble catching the winnebago. Anyway My vogon ships would rip the radar satelites off passing by it. So what do I need a radar jammer for anyway?
vogons are stupid all they do is sit around reading vogon poetry all day
Oh freddled gruntbuggly, Thy micturations are to me As plurdled gabbleblotchits On a lurgid bee. Groop, I implore thee, my foonting turlingdromes And hooptiously drangle me With crinkly bindlewurdles, Or I will rend thee in the gobberwarts with my blurglecruncheon, See if I don't! Tell me, do you like my poetry. And what does this have to do with anything?
what the crap is that doesnt make seanse
Of course not do-do. it's not supposed to.
uless i get my satalite system out.
Whaleman (author)  knex hater hater7 years ago
Damn! I guess I will just have to use my personal Death StarTM
well,looks like i gotta get mepain's sniper out and perfect ducks mg's out.
Whaleman (author)  knex hater hater7 years ago
grrrr, don't make me get my super glue out! It melts knex!
no it dosent,but ill get my soldering gun out and melt ur super glue.
Whaleman (author)  knex hater hater7 years ago
Fein benutze ich gerade meine Schweißen Fackel. Ha! Was jetzt, erwarteten Sie nicht mich, Deutsches zu sprechen, waren Sie? Muwahahahaha!!
ummmmm, yea, Didnt erwarten mich, Deutsches, yea, O.K., yea, kranker Gebrauch zu sprechen mein charzard auf ur squirtell, ahahhaahahahaahahahaha.
ich spreche Deutsch auch Sie wissen!
Whaleman (author)  knex hater hater7 years ago
Ihr Deutsch ist, Sie muß Ihr Geld von diesem Tutor zurückbekommen sehr schlecht.
يمكنني ايضا التحدث بالعربيه والمعروف والفرنسية والالمانيه والكوريه والصينية japanesse ، ahaahah وcanididaneessee.
Whaleman (author)  knex hater hater7 years ago

Mepain Whaleman7 years ago
Whaleman (author)  Mepain7 years ago
Well, the first a is supposed to be one of those "B" things, then I don't know what the rest of it is, those weren't foreign characters.
Mepain Whaleman7 years ago
Other than the missing characters... ?
Whaleman (author)  Mepain7 years ago
Whaleman (author)  Whaleman7 years ago
damn! this server doesn't recognize foreign characters!
Mepain Whaleman7 years ago
Neither do I...
Kaiven Mepain7 years ago
bunduk Whaleman7 years ago
ill shoot peas at all your heads
Kaiven bunduk7 years ago
and ill shoot foam nerf darts of doom!
ill build a spud gun and shoot you with not spuds but horse dropings (mom got 3 horses lots of ammo dude)
then ill shoot myself with LOADS of soap! HA!! :P
why would you want to shoot yourself????
& ill shoot a dead skunk at you too!!!
Oh yeah??? I'll shoot a rotten egg at both of you. Mwahahahahahahahahahahahah
fress cow poo too you
Ain't nothin that smells worse than fresh dog droppings. :)
cow poo smells worst & how would you know unless you personaly sniff them>:D
Dog poop is worse dude. And yes I have smelled it before. When a dog goes you can smell it a mile away. or have you not noticed that when you walk all the grass out in front of the dog pen? Hmmmm maybe he can't smell anything...
because he said he would shoot horse poo at me
Wicky Kaiven7 years ago
i will pwn you all with my simple block trigger knex gun of doominess :D
Kaiven Wicky7 years ago
lol! how about i use my brick knex gun of hatred >:)
Mepain Whaleman7 years ago
Don't make me call yo mama! = P
Whaleman (author)  Mepain7 years ago
your mentally ill? Wow, I should set up an appointment for you.
Mepain Whaleman7 years ago
Whaleman (author)  Mepain7 years ago
my mom is a psychologist.
Mepain Whaleman7 years ago
Well you should be set incase anything happens. : )
Whaleman (author)  Mepain7 years ago
My mommy says I am special.
Mepain Whaleman7 years ago
Psycologists always say that to their costumers.
Whaleman (author)  Mepain7 years ago
So! Sniffle, sniffle, You can't control my feelings forever! only until my medications arrive

Oh hey, did you have school today?
Mepain Whaleman7 years ago
I have school every day except Saturdays, Sundays, and Christmas.
Whaleman (author)  Mepain7 years ago
You don't have easter break, or spring break?
Mepain Whaleman7 years ago
Yes, yes, I leave my house at 7:20 AM and return at approx. 3:00 PM eastern time.
Whaleman (author)  Mepain7 years ago
Lucky! For me, officially, school doesn't start until 7:30, but they close the gates at 7:15. But I do get out a little earlier, around 2:40, but I still don't get home till around 3:10
Mepain Whaleman7 years ago
Actually, my school starts at 7:50 and lets out at 2:50. But I have study hall for the last 55 minutes of the day, so it kinda lets out at around 2-ish. I sleep in study hall.
Whaleman (author)  Mepain7 years ago
Ha! Ya, it isn't like study hall is good for anything else, I mean, What do they expect us to do? Study? Ha! For me, I don't have study hall unless it is raining during PE, and I have PE first class, so I can't do homework or anything. And this year I don't even have a field, cause that is where they put the new protable classrooms, on account of where they are putting the permanent classrooms and where they put the road that goes through my school. It is all kinda weird, but I am glad they gave us new classrooms, because the old ones were making people sick because of the mold, and they caught of fire when you tried to use the AC.
Mepain Whaleman7 years ago
I have P.E. first period too! I hate it.
Whaleman (author)  Mepain7 years ago
So do I, it is always cold.
Whaleman (author)  Mepain7 years ago
What time do you go in and what time do you leave?
i'll cut you all up with a machete mwahahahahahaha;)
Do you have a knex machette if you do or anybody else please post it
no but thinks for the idea!!
A machete? Surrender or I shall cut your heart out with a dull spoon.
me tooooooooooooooooooooooooooooooooooooooooooo!
wat purpace does the mutila i mean enhanced gray conecter serve?
Stopping the blade. : )
i'snt there a peice like that anyway - a black ball joint connector?
Whaleman (author)  jabbathegut17 years ago
There is. But if you are using it for a gun as the chamber, then you should cut the pieces, a ball joint won't work.
Whaleman (author)  darth acexxacer7 years ago
it stops the "blade" from coming too far out, but a ball joint connector will work too.
dsman1952767 years ago
ues a black balljoint insted of cutting the grey connector
Whaleman (author)  dsman1952767 years ago
You can do that if you want.
i found using a black hand works really well.
DANGIT! You beat me to finding it out.....
DrWeird1176 years ago
how does it flip open and closed?
Whaleman (author)  DrWeird1176 years ago
By using the momentum caused by the flicking of your wrist.
I changed the female connector for stopping the blade to a black hand. Works better. I used this as a handle for a pistol, like Metal Gear Solid CQC.
vinman926 years ago
I have a knex bqailsong that I made its way big and not to hard to make should I post
Whaleman (author)  vinman926 years ago
No, because bqailsongs don't exist. Did you mean "Bail Song"?
sorry man you know what i mean i was in a hurry but what you think otherwise
It's actually balisong.
there is no video
Whaleman (author)  daytje psv 4 life6 years ago
Yes there is. Did you not click on the .avi file?
you need to kill peices for this?
Whaleman (author)  I_am_Canadian7 years ago
No. The decapitated piece can be replaced with a ball socket.
juneapaluna7 years ago
I mad one without the orange bendies but it bends a little bit,Im too lazy to post it unless you guys want me to.
i want to know what you used instead
ojochris7 years ago
where did U get the Short Bendys? P.S. Isn't there a piece that is a decapitated grey piece?
jli1 ojochris7 years ago
i have mutila... i mean enhanced grey pieces a lot lol
ojochris jli17 years ago
Ok, you don't need to, uh... how can I put this... "injure" a grey piece if instead of a red connector use a green one on the knife.
jli1 ojochris7 years ago
well, i haven't made it anyways, so don't bother to tell me lol
I mean the hinge of the blade (I wasn't too clear in the last comment)
ojochris jli17 years ago
jli1 ojochris7 years ago
response in 15 mins lol
Whaleman (author)  ojochris7 years ago
From a knex set. You can use a ball-joint connector if you want.
J_SCAP7 years ago
hey can you make a blade that dosent use bendy peices (i dont have any :( )
ojochris J_SCAP7 years ago
Post pics of it.
thebboy7 years ago
ya i made it. would post picture but camera act weird.
Why does everybody talk about random stuff?
dramamine7 years ago
I want to build this but I only have the large, green bendable knex. would they work if I extend the handle or anything?
Whaleman (author)  dramamine7 years ago
It would probably work.
Okay, I'll try later after I've finished my little knife/swordy type thing.
i want to do this but i dont have the orange bendy sticks. is there anything to replace it?
Whaleman (author)  GorillazMiko7 years ago
one yellow rod will work
woohoo6597 years ago
(removed by author or community request)
Whaleman (author)  woohoo6597 years ago
um, sure. You do that. Oh, hey, I have to ask you a few questions from an ~~ Insanity ~~ Fun Quiz. 1-Are any dead relatives in your room? 2-Is Jesus, Yahweh, Buddha, Allah, Moses, or anyone like that in your room? 3-If the answer to one or both of the previous questions yes, then can you talk to them? What are they saying? 4-Are there voices in your head? What are they saying? 5-Do you have an unstoppable urge to drink coffee?
Mepain Whaleman7 years ago
1-Yes. 2-No. 3-They want to go and watch "Bee Movie" later. 4-Yes, they are saying, "BRAINS!" 5-Yes.
Whaleman (author)  Mepain7 years ago
my theory and remedy. You are high on marijuana. Remedy, have someone else prepare your coffee (i.e. not grandmama gerarda, she died ten years ago, she shouldn't be making your coffee).
yeah ok
smidge1477 years ago

yer check out my computer lol soz if this is spam.
Whaleman (author)  smidge1477 years ago
Cool, did you make it? Looks EVIL (-.-) BTW No, of course I don't consider this spam, hell, I'll even go as far as showing my own PC
Whaleman (author)  Whaleman7 years ago
yes, that is mike rowe in the background
gotja Whaleman7 years ago
dirty jobs?
Whaleman (author)  gotja7 years ago
Ya, he is slashing dead salmon in half.
HAHahahaha!!!!!!! I like that one. I thougt it was funny when it didn't cut all the way through. (it's cool he is cutting and this is a knife instructable. i don't have bendy pieces, but no prob it's a hacksaw now. I modded the morretti so it's a plasma sniper looks the same as the one on Time Splitters future perfect. ( also that game is COOL )
yes my computer is custom built except the case i didnt make lol
Whaleman (author)  smidge1477 years ago
Oh, where'd you buy the case? i dont think they sell it any more but other site do its called cobra case.
Whaleman (author)  smidge1477 years ago
oh, ya, I probably wouldn't buy it cause shipping from the UK is expensive and takes a long time, I got my case from costco
(removed by author or community request)
nice, but check out my blade! :D

Concield Blade by Josh
Whaleman (author)  darth acexxacer7 years ago
It doesn't need a gun, that is why it is a knife and not a bayonet.
i know the gun is for your enemy to think thats all u have left and then boom there down
darkmuskrat7 years ago
maybe replace the outside or the "blade" with an actual knife. it might be more intimidating
Whaleman (author)  darkmuskrat7 years ago
Yeah, but I could get sued for that!!!
whoever7 years ago
Yeah i agree with gizmoman that doesnt make any freakin sense.
you know me7 years ago
i kill you all wit the DOOM3 60 cal. CHAINGUNS(aka S.A.W. BULLET BELTS!!!!! [insert evil laugh here]
Whaleman (author)  you know me7 years ago
Oh yeah! Well lets see how well that does after it has been NUKED! Muwahahaha!
if you are going to argue over who got the better weapon then ill get my trusty 'ol lightsaber (may the shwarts be with with you)
Whaleman (author)  the gizmoman7 years ago
That is actually a ring, thank you very much! I think space balls is better than star wars.
the shwarts is in you, the ring came from a crackerjack box (who do you think is better darth vader or dark helmet??)
Whaleman (author)  the gizmoman7 years ago
Dark helmet, DUUUUHHHH, darth vader is all burned up, and dark helmet only burns himself when he tries to drink coffee
i was thinking dark helmet too darth vader was too whiny befor he got his parts forcefully removed(burned off with every thing else in revenge of the sith. sure thing jack sparrow & vader never met ;)
Yep. Jack would make some comment about his being a eunuch not realizig it was actually true. Then Vader would try to kill him by force-choking him. Than Jack would save himself and kill Vader by trying to talk his way out of it. Vader is not a thinker so the thinking part would be such a shock, that he'd have a heart-attack and DIE!!!
don't you mean "brain-attack"
Whaleman (author)  the gizmoman7 years ago
Yep, but the pirates and the clones never met either, it would have been cool to see what would have happened
i hope your were talking about the undead crew inthe 1st potc
Whaleman (author)  the gizmoman7 years ago
Yeah, I was. It would be cool. Invincible pirates versus an unlimited amount of clones.
Personally I think that the undead pirates would win. Unless Jack and Will were somewhere around with the last medallion and a knife...
Yeah, the pirates would win, they can think for them selves, while the clones only know how to kill, not to be strategic
ill gust set off halo and run into a bolt hole( i think this is a extra dimensional pocket)
im telling ewihelm
on wat?
oh also i think he has a radio station! eric wihelm on an am station lol(im seriuos)!
J_SCAP7 years ago
yay im usefull
Whaleman (author)  J_SCAP7 years ago
Dude6877 years ago
that's sweet!!!!
Whaleman (author)  Dude6877 years ago
Whaleman (author) 7 years ago
Awwwwwww, fine, prevent a nuclear war! See if I care!
bunduk7 years ago
hey i made it and have moded it so it stays in and out really well and comes ou with a little switch that is easy accesible check out my new forum topic
Whaleman (author)  bunduk7 years ago
Vynash7 years ago
i love this thing it rocks
smidge1477 years ago
ill just use a straight peice and use it as a gun un-jammer
Whaleman (author)  smidge1477 years ago
knexguy7 years ago
looks nice, i will build it now! first comment!
noob!!!!!haha u used first comment btw this knife looks funny but i wont be building as i dont have bendy pieces.
Whaleman (author)  smidge1477 years ago
i wasnt calling you a noob lol ur kl
Whaleman (author)  smidge1477 years ago
I know, you were calling him a noob for saying first comment. I was saying "awww" cause you don't have bendy pieces
flames103917 years ago
Vynash7 years ago
im gonna build it now looks awsommmmmmeee
Kaiven7 years ago
with the band on, it maes the knife stick out a tad
Kaiven7 years ago
that looks... PRETTY!!! PRETTY COOOOOOL!!!
Mike Cortes7 years ago
Dont have the bendy pieces either, but i might actually put a knife, lol. ooooooooooooooooooooh dangerous. ill make one later when i get home from Cornwall to London.