Introduction: MKS-2

Picture of MKS-2
This is my second K'nex safe, but the first one was only a slide show, while this is an I'ble. This one is not the same one, and while it has many similarities to it, it does have some (rather significant) differences which make it better and probably more practical than the first.

My First K'nex Safe

More Instructables by Me

  • Uses 2 keys
  • Has 6 bolts
  • More compact than the first
  • More storage space than the first
  • Pretty solid, door is securely held in place by bolts

Step 1: Components

Picture of Components

Make the following in the quantity stated:

Image 1: Make 1. Part A
Image 2: Make 2. Part B
Image 3: Make 3. Part C
Image 4: Make 4. Part D
Image 5: Make 6. Part E
Image 6: Make 6. Part F
Image 7: Make 1. Part G
Image 8: Make 4. Part H
Image 9: Make 1. Part I

Step 2: Construction

Picture of Construction

Follow the images:

Image 1: Add red and white rods to Part A.
Image 2: Add Part B & H.
Image 3: Add Parts C ,& 2 F, and 8 blue spacers.
Image 4: Add Part D.
Image 5: Add 3 Parts E.
Image 6: Add Part D.
Image 7: Add Parts C ,& 2 F, and 8 blue spacers.
Image 8: Add Part D.
Image 9: Add 3 Parts E.
Image 10: Add Part D.
Image 11: Add Parts C ,& 2 F, and 8 blue spacers.
Image 12: Add Part B.
Image 13: Attach rubberbands on both sides of the safe as shown.
Image 14: Add Part G and white rods.
Image 15: On the back, add red rods with tan clips, Part H, and green connectors.
Image 16: On front, add metallic blue clips and Part H.
Image 17: Add Parts H & I.

Step 3: Use

Picture of Use

To use first make 2 keys like those in the first image. Then insert them in the holes on both sides of the safe as in image 2, and make sure that the end of the keys goes into the hole in the gray connector in the back as in image 3. Then turn both keys towards the middle as in image 4, the left key clockwise, the right key counter-clockwise. That should pull back the pins which lock the door of the safe and you should be able to open. It may not work too smoothly because of the rubberbands but you can always help the pins move yourself. Then to close, make sure the pins are back, close the door, and release the pins and remove the keys to let them insert themselves in the door and lock it. If they don't do this automaticly, move the door around so the pins go into the holes in it.

If you want it to use different keys, then you'll need to modify it yourself to accept different keys. The safe can be modified quite a bit and it will still work.

Note: This safe is not created to protect valuables and important objects. It can be broken into with relative ease so do not use it as real safe. I am not responsible for any losses, damages, and/or injuries and deaths caused by this instructable. That responsibility is yours.


danroy99 (author)2012-02-25

I just finished building this and I think it's FANTASTIC! The only issues I had were piece shortages. Such as how I had to use yellow connectors for the lid instead of orange, but not a problem. My biggest problem was hinge shortage. But I followed the advice you gave earlier to snosageman99 and put 2 and the front and it worked fine. This is a great safe! It's actually pretty tough and secure. (Except for the front and back of the actual box) These were great instructions, it's a great safe, and I had a great time building it. Keep up the good work!


Masterdude (author)danroy992012-02-27

Yeah the thing does use a whole lot of parts. I myself would have changed some things if I had the pieces. Glad you like it and thanks.l

lilnorm123 (author)2012-01-06

THIS IS TOTALLY EPIC!!!!!!! I'm gonna build this when my shipment of hinges come in. I've only got 2.

Masterdude (author)lilnorm1232012-01-07


H1T4TCH1 (author)2011-10-16

Wow, I definately going to build!


Masterdude (author)H1T4TCH12011-10-16


MegaMetal8 (author)2011-10-16

So Good I Might Even Build!

Masterdude (author)MegaMetal82011-10-16


knex builder36472418 (author)2011-10-15

shiiiiiiiiiiiiiiiiiiitttt that is nice dude, btw i gave up trying to build your other one, it was so hard lol

Thanks, this one might be easier to build than that one. The first one's mech was a bit more complicated than this one.

TheRacker (author)2011-10-15

Looks good. I like the way the 6 bolts lock the door.

Masterdude (author)TheRacker2011-10-16


~KGB~ (author)2011-10-16

Thats pretty nice!

slaveboy2000 (author)2013-01-30

i don't have enough hinges is their another way?

Masterdude (author)slaveboy20002013-02-08

There might be but it would require some heavy modifications and probably making it larger.

goliver5 (author)Masterdude2015-11-05

hi I'm new to knex so can you post a small knex lock/safe please I really like your other but I don't have enough money to get more knex I only have 1000 knex please contact me to let me know if you can do that my gmail is or you can contact my intractable account

theoffice101 (author)2012-09-03


Masterdude (author)theoffice1012012-09-04

What seems to be the problem?

theoffice101 (author)Masterdude2012-09-08

When i put the keys in and turn them, the back right bolt retracts, and nothing else

~Aeronous~ (author)2011-10-24

Great safe you got there. I don't think that green rods would be very strong but whatever.

Masterdude (author)~Aeronous~2011-10-25

Thanks. I think that in my earlier I used white rods as bolts, but since there are 6 green rod bolts and they fit rather snuggly in the door, it is pretty strongly locked.

whered all my green rods go?!?!?!....oh
i dont even have enough of them can i change it???

I hate it when that happens. Especially when building someone's I'ble and I don't have enough parts to make it work. On the internal parts you could minimize part use by simplifying the internal structure. It might still work. You could also take the door and instead of using O. Connector-G. Rod-O. Connector-G. Rod-O. Connector with O. Connector-B. Rod-O. Connector. Then if you get rid of the middle bolts you should save atleast 36 G. rods

the thing is i dont have manyMORE GREEN RODS.


I don't know. If indeed you have that little green rods then I'm afraid you might not have enough to make it, even with drastic modifications. I quess you could make it thinner, for example get rid of 4 of the bolts and get rid of all between them. That, however, would be quite a drastic change in design. It's probably doable but you'd have to change many things such as the door and key to make it work.

Snosageman99 (author)2011-10-21

i dont have that many hinges can i use something else

Masterdude (author)Snosageman992011-10-22

You could not do all the bolts, and only make as many of them as your resources let you.

Snosageman99 (author)Masterdude2011-10-22

ok if i made 2 where would i put them. I know there are 6 spaces ( 3 on each side but where would i put them. On your one there is six bolts back, middle front but where would i put it.

Back Middle or Front.

Masterdude (author)Snosageman992011-10-23

I would say one on each side, in the front, they are easiest to turn if they are placed in the front.

Snosageman99 (author)Masterdude2011-10-23

ok thanks....built it and it is awesome 5*

god this will take long!
im only on the 3rd pic.,step 1!!!!!
i started at 12:00 pm!!!

MegaMetal8 (author)2011-10-17

Built it.

Can't get it working. I Can't turn the key to push the pin/lock parts.

Masterdude (author)MegaMetal82011-10-17

Well, if you've made it correctly, then you might not be inserting the key correctly, the tip of the key's rod should go into the gray connector's hole, or the rubberbands might be on too strong and might make it hard for the bolts to retract. PM me if you still have problems.

MegaMetal8 (author)Masterdude2011-10-18

Without ANY elastic bands only the first pin on each side works.

Masterdude (author)MegaMetal82011-10-18

What rod do you use for the key? The standard gray rods might disfigure and the torsion might not get to the back pins. The black ones are stiffer and would probably work better if you use them.

MegaMetal8 (author)Masterdude2011-10-21

I Used Black Rods cause I thought of what you said as I built it.

Masterdude (author)MegaMetal82011-10-21

Well, I don't know, usually it would work for me, even though sometimes it would take a couple turns to turn back the back ones.

MegaMetal8 (author)Masterdude2011-10-22

Im just gonna break it up.

Shame it didn't work though.

The all round build is very compact and clean though - good job!

Masterdude (author)MegaMetal82011-10-22

Too bad that it didn't work for you.

MegaMetal8 (author)Masterdude2011-10-23

Ya. "/

Fred the evil puppet (author)2011-10-21

i may even give up on my improved zkar mechanism to build this!

MegaMetal8 (author)2011-10-16

Building. Just finished pic 3.

Masterdude (author)MegaMetal82011-10-16

Good luck building it.

MegaMetal8 (author)Masterdude2011-10-17

Failed - Read other comment.

james4 (author)2011-10-16

lol at first look i thought oh hey a knex bomb

Masterdude (author)james42011-10-16

Really? Like what bomb did you think it looked like?

james4 (author)Masterdude2011-10-16

idk kinda like one that you plant on the ground and it explodes kinda like in counterstrike

About This Instructable




Bio: I make K'nex guns, specializing in semi-automatic, RBG-Slingshot hybrid systems which i use in most of my guns. Note: I am not responsible in ... More »
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