How to Make a 3D Printed Key(FULL TUTORIAL)




Introduction: How to Make a 3D Printed Key(FULL TUTORIAL)

Hi everybody,

It is very clever to have a spare key hidden somewhere around your house. In this project I am gonna show you how to duplicate a steel key and 3d print a plastic one which can lock and unlock the door as easy as a steel one.


Step 1: How Is a Key Structured

- Let's start this project with the most commonly found house key.

- There is a lot of other types and sizes of keys but they basically work in the same way.

- Firstly, we need to see how our key is structured.

- The most difficult part will be creating those slots, because they are very small and they are all different shapes and sizes.

Step 2: Scanning and Photoshoping...

- The best method to get the profile of our key is to scan it and photoshop it later on.

- For best results try scanning it on a higher resolution so you will get better picture, 1200 DPI works best for me.

- You may need to do the preview of a scan to see if your key is in the scanning area.

- Once is that done save the file and open it in photoshop.

- Increasing brightness will make tracing much faster and more accurate, also be sure to capture even the smallest slots of the key.

- After tracing paint the key black and background white.

- You can also make a white hole but it is unnecessary.

- When you are done, save the it as png image and close photoshop.

- Now open it in any vectorizing program, vectorize that image and export it as .dxf format.

Step 3: Designing the Key

- I start with importing dxf file into 2d sketch. Then I measure height and width of the original key and do the same in solidworks.

- Steel key is 2 mm thick so I extruded the sketch for the same amount.

- Then I cut out the 3 slots so they were looking close enough to original. These slots are very small and it is not so important to make them exact because we will sand them after printing.

- When you finish, save the file in .stl format and open it in a slicing software

Step 4: Printing and Finishing

- I printed it at the finest settings with no supports so it could print as accurate as we draw it.

- For best results heat your bed and print it at lower speed as usual.

- Export file to g-code format and send it to the printer

- I used black pla with external fan for better cooling

- Now just wait till your key is printed

- And there you have it, 3d printed key

- If you try to insert the key into the lock it probably won’t fit in so we need to sand it a bit and make its slots larger. I did this with small files and it worked perfectly

- The key is ready to be tested

Step 5: Testing the Key

- You may need to use a drop of oil for smoother insertion and we have done it

- I was very impressed that this actually worked as it should

- You can also print yourself a bump key. It should work like the steel.

- And this is how to 3d print a standard house key.

Step 6: Thank You

Thank you guys for watching my tutorial. That really means something to me and it really keeps me motivated. I also made a video with better instructions on youtube so please subscribe, like and share it so other people can see it.

You can help and support me on patreon. With that money I will upgrade my tools and renovate my workshop.

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Music by:

-Distrion & Alex Skrindo - Entropy [NCS Release]

-Joey Miceli - Without You (Instrumental Version)

Thank you for your support

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    I would be careful with 3D printing keys for stiffer locks and larger doors, I've seen people try to do this and they had the key snap off inside the lock! I wonder if there is any way to strengthen the key to avoid that problem?


    Reply 7 years ago

    you can alluminium cast the 3D printed key, or order a metal 3D print online (that would be pointless since ordering key copies would be cheaper)


    7 years ago

    puts plastic key in a lock, key snaps, stuck forever outside : )