How to Make a Credit Card Knife - Cardsharp-




Hi guys,

Today, I will show you how to make a foldable knife with the size as that of a credit card. Why i did that? In few days ago, I had a trip to jungle with my friend in 5 days. All knifves we have were too large. After going home, i searched for a knife that is small but affordable to carry. The I found card sharp, I decided to make my own one.

Check out the video :

Here are the material that you'll need:

- 1 x Hard Plastic Card

- 1 x piece of flat steel

- Tape

- Scissors

- Hot Glue

Step 1: Draw the Shape of Handle

Firstly, You need to draw the shaoe of handle on the plastic card. I will devide the card into 4 parts as in image above. Please keep your mind the ration of those part. This step will require you 1-2 minutes.

Step 2: Cut Them Apart

Cut all parts seperately.

Step 3: Draw Blade on Metal and Cut It Out

Use a peice of metal to make your blade. Here i use s corrugated iron sheet. Draw the blade on that then cut it out

Step 4: Stick Plastic Parts Together

A after having handle part, use tape to stick them together. I recommend electricity tape due to its durability and softness.

Step 5: Stick Blade to the Card

Now you can use hot glue or iron glue to stick the blade to handle. Pay attention to this step, the blade shosuld be glued to the smallest part.

Step 6: Sharpening

In this last step, I recommend a 1000-grits stone to sharpen and smooth your blade. Then you can use a 6000 grit for honing the blade. In sharpening process, you should add some water and oil to make it smootheir and easier. Thank to that you will have a much sharper knife. And be carreful while sharpening because you can hurt yourself. Now, after fisnishing this step, it is high time to enjoy your work.
You can check the video here :



    • Cardboard Challenge

      Cardboard Challenge
    • Toys Contest

      Toys Contest
    • Warm and Fuzzy Contest

      Warm and Fuzzy Contest

    12 Discussions


    1 year ago

    good idea. however, u should use more durable tape. i am not sure that elẻctic one is durable enough


    1 year ago

    good one, just be careful to make some sort of safety mechanism to keep the blade safe while in the pocket/wallet.


    1 year ago

    Wow! neat idea but I think you'd better choose a harder metal to make the blade and your blade should be sanding more to have the best sharpness. Btw, it is really useful


    1 year ago

    Good job! How did you make those animated photos? I have a plan and wwant to make its photo like yours. Thanks

    1 reply

    Reply 1 year ago

    Thank You! There are many platforms that allow creat your GIF image such as ficker, imgur.... I converted my video into GIF online on imgur, so you can try it. Good luck


    2 years ago

    This is a neat idea. :) You should enter it into the Knives and Blades contest!

    3 replies

    Reply 2 years ago

    Thanks! where can I enter that contest? could you give me the link?


    Reply 2 years ago

    Unfortunately the contest closed for entries at midnight January 19th. You can check out what contests are running at any time here.