A "Ghetto" Retractable Utility Knife AKA "GRUK"




About: "Black socks and Birkenstocks do not maketh the geek. I would argue that the essence of geekitude comes from within. To the true geek, it's not enough that things work. He or she must know how things work. A...

You may or many not know that I’m currently living/stuck in Kabul, Afghanistan.  Being here has its perks despite what you might think.  For one, living here forces you to be innovative, resourceful, and creative. 
One of the problems I was having was never having a utility knife where I wanted them.  Either they would get confiscated, or picked up by locals with sticky figures, or just lost.  I know that these are cheap items, but when the nearest Home Depot is 8000 miles away, you find other ways to get by. 

So enters my Ghetto Retractable Utility Knife or ‘GRUK.’  Its only requirements were that it needed to be made with found objects, I hand no real tools to make it with, and it needed to be ‘somewhat’ safe.  (To be honest, safety is never a real concern of mine.  I mean I live in a war zone.  Just yesterday 3 cars bombs exploded down the road.  Last Monday there was a massive attack on the city I’m in, so if I cut my finger on a knife, oh boy.  8>) (this is just me; feel free to be as safe as you want.)  Safety is only a measure of comfort.  Each individual needs to find their own. 

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Step 1: What Do You Need?

OK, here is what I found, a piece of cardboard, a piece of wire and an old blade from another knife.  (Yes, I understand the irony of finding a knife while looking for parts to make one.  But there is an excellent ‘ible here from a guy that makes them from scratch.  Here is the link…
That is what I was planning on doing before I found the knife blade.)

Step 2: Make/sharpen/clean the Blade.

Depending on what you are starting with for a blade, follow the aforementioned ‘ible to get it to resemble a blade. I just needed to clean and sharpen the blade I found on the sidewalk.  (Note, in Afghanistan, sidewalks are hard to find, but just about every building is made of masonry.  So I just needed to walk outside and rub the blade on the side of the house to get the desired results.  BTW, if your co-workers didn’t think you were strange BEFORE they saw you rubbing the building, they will after they see it.  Especially if you say “I just wanted to see if a Genie would come out.”  Like I did! 8>)

Step 3: Making the Handle

To make the handle, cut a piece of cardboard the width of your hand.  Now, just tightly fold the cardboard around the blade.  It’s pretty simple.
You want at *least* to cover the blade twice.  It will wear through the cardboard if you open/close it a lot.  So make sure that you replace the cardboard before it falls apart.  (note, the wire will provide a small measure of protection if it does cut through the cardboard.)

Step 4: Secure the Handle

I wrapped the wire around the handle to secure it firmly.  This worked out perfectly for my needs.  Note, the blade can move in and out of the cardboard, so you can retract it.  Just tighten or loosen the wire to increase or decrease the friction on the blade.

Step 5: Decorate

Not really required, but I figured I’d make the knife “mine” by just jazzing it up a little bit.  I’m no artist.

Have fun and don’t cut yourself!


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    43 Discussions


    4 years ago

    How are u struck

    well, i guess i can tell you guys about the shovel and socket wrench i keep next to my bed. for self defense purposes :P


    Reply 9 years ago on Introduction

     Aaaaa..I only have a cheapy stainless steel knife stuck in my bed stand...


    Reply 8 years ago on Introduction

    I have like 8 different pocket knifes, a homemade kodak tazer, 2 lock knives and a home made cross bow by my bed. Why so much? Incase some one annoys me.

    funny thing is... im not joking


    Reply 9 years ago on Introduction

    I would never use anything that could cut or damage somone, only blut objects or electrical.

    if zombies invade and all you had was a lead pipe, simalar to the one i have next to my bed, how could you cut things? you have too consider utility purposes.


    Reply 9 years ago on Introduction

    I once fell asleep listening to music i managed to wrap it round my neck and make it so the when ever i sit up it tightens 0.o

    Scary thing is, I actually know someone who has an M4. I've never really met the guy, I just know he has tons of $$$ and collects guns.


    Reply 8 years ago on Introduction

    if have a pvc pipe by my bed. one time my sister was sneeking in my room and she tripped it woke me up and i beat her with it