This is a tutorial on how to make a Ballistic Knife. A safe one out of cardboard or foamboard.

This kind of knife is a weapon that shoots. The blade is in place and you can use it as a normal knife. But, if you need to, you press a button and the blade goes flying out of it.

I also have a video tutorial on this project. You can watch it at the bottom of this page.

The Template is here

Print up the template. It has all the patterns for this project. You can download the template here.

Note from Will: The Template and the tutorial are both absolutely free! But would you consider a donation of $1 to support my work? Paypal makes it very easy and safe. Click here to donate $1 - Every little bit helps Will to keep making great tutorials and templates. Thanks!

Cut out the ten pieces and lay them out on your foamboard or cardboard. Trace them onto the board.

Go ahead and cut all ten pieces out.

Here are the ten pieces. Now you see that there are four little squares. The bigger pair are the stop. Glue one right on top of the other. Do the same thing with the smaller squares. Glue them together. Those smaller squares are the trigger.

Now glue that assembly of the larger square right onto the side piece. At the end of it . Be sure the whole square hole is exposed. The stop should be right up against it but not cover it.

Now let's make the handle box. Glue the two sides on just like this. Then glue the fourth piece right on top of it, making a box.

There you go. The box is done. Notice how the rubber band slots are both on this end. And you can see the stop inside there. That stop is what catches the blade and locks it loaded.

Now glue the guard on.

Cut the rubber band and feed it through one slot, through the handle and then out the other slot.

Then glue it down on each side. Now, you really should test the tension of it before you glue it. This way you can adjust it to maximum power before glueing it. You don't want the rubber band taught from one side to the other. There is plenty of slack inside that handle.

Now insert the knife blade and give it a try! The red arrow shows the notch. That part is what catches on the square stop you glued inside.

Now insert the button. This is the smaller square assembly. It should be a snug fit. You can trim it as needed.

If you push that button in further it releases the blade.

All that remains is to paint it. Paint the handle brown and the guard and blade silver. Notice the notches in the blade. These are not in the template but you can add these yourself if you like them.

Here is the video tutorial:

More projects like this one:

Make a Spiderman Web Shooter that Really Works - This is a fun rubber band powered project that is easy to make. It shoots a web.
Make the Spider man web shooter

Make a Rubber Band Gun

All you need is a sheet of foamboard. I figured out the engineering of this and it works really well. Fires great too. How to make a rubber band gun.

Elmer's Acid-Free Foam Boards, 20 x 30 Inches, 3/16-Inch Thick, 2 Boards per Pack, Bright White (902015)

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