Assassins Creen Hidden Blade/DAGGER




Introduction: Assassins Creen Hidden Blade/DAGGER

About: Hello There! My name is Timothy and I am 18 years old and I love biking, Rc, arduino ,gadget hacking and 3D designing. I'm currently studying in PATTS College of aeronautic As an incoming 3rd year Avionics s...

Get ready cosplay enthusiast and makers alike we are going to make something you all know about Its called the Assassins Creed Hidden blade.Its designed by me based from all the videos I've watched in youtube with out having an exact blueprint that has dimensions on it. All I really did was i kept on rewatching the same video over and over and over again until I got each part to work inside my head. After that I drew some templates that would fit my arm, then from that I started designing/ modelling and printing my own parts.The blade is not 100% complete but it works like a charm the only thing missing here is the automatic pull back mechanism where the blade goes back inside automatically, instead you flick a switch to retract it back but popping it out is no problem since that is the main goal of this hidden blade. Worry not I will soon make another ibles wherein the dual action works properly. But to do that I need you full attention and support to make this happen because I just started 3D modelling in sketchup and Autocad So feel free to message me and ask for the .skp or Dwg files C'mon and lets help one another.

For my entry in FORMLABS CONTEST: If I win the Form 1+ 3D printer, I will design and engineer interesting mechanisms like this that will satisfy my need for precision and speed. And with the printer I will make good use of it in making robots and gadgets like "SMART WATCH" "SMART DOLL", I will use the printer for my future project: "Perpetual GENERATOR" Something I've been thinking about last year its just, i'm still learning the ways of 3D modelling since I havent really mastered the whole thing. I will show the world what a kid can do with a 3D printer and I will show everyone why they should get a Form 1+ 3D printer.

SPECIAL THANKS To ammnra and Imdeepain for their wonderful videos in youtube, they sure gave me a lot of ideas and problems during the build hehehehe

This hidden knife will need some sanding and some recyclable materials like springs from old pens and screws from your old toys.

"BLADE MODES" Make your imagination run wild!

Use it as a

-hidden dagger

-Hidden Knife

-Hidden blade

or just a show piece!


TOOLS and materials you will need for this build

1x Clear epoxy

1x Super glue

2x Thumbtacks

1x Rubber band standard

2x Paper clips

1x Pen spring

1x Long Nose

1x Dremel

1x mini drill with 1mm drill bit

1x Tweezers.

6x M3 x 5 screws

Sand paper "GRIT" P120 and P60

Step 1: Blueprint~

The blade has 11 printed parts, and each part has its own print setting
For every part I will indicate the print setting or feel free to set your own to hasten the print But if you want quality prints better use my setting.

Now try looking at the image.... looks easy right? Its a simple yet complicated mechanism I would say, because of all the friction that occurs inside during the action.So the key here is precision and soft surfaces.

Step 2: Print #1 BODY


infill: 20-40%


Shells: 0

You may need to sand some surfaces here but if the print is smooth I guess there is no need to do so.

Step 3: PRINT # 2 BLADE


infill: 70-80%


Shells: 0

Same as the Body and I did this so that the blade wont break of easily so as the body.

The blade will need some sanding or trimming, look closely at the pic to see where exactly

Step 4: Print #3 LOCKERS

You will need to print 2 of these


LAYER HEIGHT : 0.1 its small so why not make it HD right

Shell: 0

Step 5: Print #4 EDGE

EDGE is a part of the body you will need to Sand both sides of it and glue it on its proper place on the body.




Step 6: RPINT #5 MECHS


Dont get confused by these parts

There is the MECHL1 and MECHL2 for the left part and MECHR1 and MECHR2 for the right part

You will need to glue MECHL2 onto MECHL1 Follow the picture to get an idea of what to do. And do the same thing for MECHR1 and 2

Infill 60%

Layer height: 0.20

Shell : 0


THE SWITCH Will need sanding~




Step 8: Print #7 COVER


Finally the last part

INFILL: 100%



Step 9: Print #8 Velcro

Infill 20%

Layer height : 0.25

Shell: 1

This part is optional~ Super glue it on the sides of the body so that ou can attach your own velcro

Step 10: Assembly #1

MAke sure every part moves just right on the body including the blade, switch and MECHS.

The goal here now is to mount the locks on the chassis now how to do this?

1. Get your thumbtack and pin it through the holes on the LOCK, ones done

2. Position the lock on the edge just like on the photo.

3. Pin it down until you get a small dent on the surface of the plastic.

4. On that dent drill it vertically with a 1mm drill bit. Pin that hole with some of your extra thumbtacks and make sure its firm and locked in place.Apply some epoxy/super glue on the base of the body to further lock the position of the thumbtack.

5. Do the same for the other side~ just make sure the locks move freely.

Step 11: Assembly #2 Springy


You will need old pen springs.

1.Get your long nose and expand the spring by stretching it the goal here is to make the spring metal flat as possible

2.Cut 2x 22mm flat spring metal "it does not need to be exactly flat~"

3.Go back to the body and look for the tiny hole there you will glue the spring metal

4. Apply a generous amount of super glue on the spring metal and insert it inside the hole using tweezers

5. Add some more super glue on the surface of the hole

6. Let it dry~

7. Bend the spring metal at certain angle the goal here is to make the lockers point out

Step 12: Assembly #3 MECHS

By the looks of the image you will get an idea of what to do so just glue it up ~

You will also notice there is a hole on it and that is where you will put your paper clips.

1. straighten the paper clip and trim it

2. With the remaining metal you see make a hook~

3. Do the same thing for the other MECH

Step 13: Assembly #4

Now you assembled the mechs its time to see if it works~

Get a small rubber band and hook it onto the mechs

place switch at the center and try it out if it works fine then cover it up and screw it in place

Step 14: Assembly #5 CUt That~

There is this excess metal on your thumbtack right so we cut that using a dremel

Cut this infront of a fan/Aircon. because it may melt the plastic as the metal heats up.

Look at the picture to get an idea of where to cut exactlyMe

Step 15: Congratulations~

Your done!~ Enjoy your hidden knife

And if you noticed the hole on the switch you can attach a string going to your ring and from that you can turn the hidden knife into a hidden blade! its just a single action not the dual action you are looking for but dont worry I will be posting another build that features the dual action hidden blade~

Step 16: Trouble Shooting

The hidden blade is designed with the help of some physics

So I'll give some of the problems i've encountered before that may help you with your problems too.

Problem 1. The blade does not pop out "completely"

Fix 1: Sand the blade on its sides and smoothen the walls of the body where the blade is placed (IMPORTANT)

Fix 2: Make sure that the Mechs move smoothly along its rails

Problem 2 The blade pops out but the blade does not lock in place

Fix 1: stretch your rubber band make try making the tension weaker, sometimes the launching action is to fast/hard that the lockers dont catch the blade, instead it bounces of way past the locks.

Fix 2: The hooks try replacing the hooks by printing new mech this time make the hook a little further to lessen the tension.

Comment your problems let me see what I can do

Just REMEMBER SANDING is the KEY, Friction is your enemy.



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    44 Discussions

    This blade have only one not auto retracting like IMDEEPAIN one.....but it's very good is one of the best 3d printable hb in the net!

    how much sanding???
    lil, fair, alot ??

    What does it weight approximately?
    like how many grams ?


    1 year ago

    How much for 2 to be printed?

    Hi this Is incredible! I have autodesk inventor, and would love to try to improve it, can you share the part and assembly files with me please? also are the shared files the one that is shown in the video with expanding and retracting action? thanks!! please reply to me at

    5 replies

    Are you still looking for the model?

    I lost the files in my old desktop computer.... the thing just broke down on me ...ow well

    You can re download them from this page...

    .STL file = Uneditable.... well it can be but not entirely anways I lost interest

    I lost the files in my old desktop computer.... the thing just broke down on me ...ow well

    could you make a wooden blade or something or upload step by step instructions

    I uploaded the STL files... I will upload the latest dual action hidden blade "FINAL" soon just need to wait cuz I have a lot of project to prioritize first

    If you atatch a rubber band to the back and the switch it would retract back, or you could do the sound hound system like imdeepain

    1 reply

    I wont publish the full dual action this was my progress 2 months ago i just finished the sound hound system too. I will keep the secret safe

    Great work! I've tried making this blade about 8 times, and failed completely. Hopefully, the 3D models should help improve my accuracy. Thank you.

    Also, try adding an extension spring to the switch, with one end coiled through the hole in the switch and the other end fixed to the rear end of the box. That way, when you extend your wrist, the blade fires out, and when you bring your wrist back, the blade retracts.

    2 replies

    ;) i'm actually done with the over all design with the dual action feature.. im just waiting for the right contest to enter

    Ah, that's great! I would definitely vote for you :) I'd love to see the changes you've done. Have you tried making the blade with an additional sleeve like ammnra's blade? That would make way better than it already is. What is the total volume of all the parts? How did you get it printed?

    Pdf plan please..

    thank you