Make a Realistic Prop/Fake Knife

     Are you filmakers out there wanting to incorporate a knife fight in your action films but don't want to put your actors in danger? You could dull a knife but that still presents risks AND up close shots can reveal the knife's true edge. Quit stressing out and look no further! Today I will show you how to create a prop knife in under half an hour (excluding paint drying). I have also created this instructable in  a way that will keep you from having to take trips to the store. It uses no advanced tools. Just objects you can find around your house! I in no way have copied this idea from anyone. I was just a filmmaker that wanted a knife to use without putting my actors in danger.

DISCLAIMER: I in no way am responsible for what you do with this fake knife. I am also not responsible for any damage that is caused during and after the process of creating this knife. Also while this knife is safer than a real knife, it may still be able to cause harm depending on the way you have created your knife.

Now that we have that seriousness out of the way, continue onto the first step where we will learn what is needed in order to create our own prop knives!

Step 1: What You Will Need

I purposely created this instructable in a way that is 1. easy for someone to understand, 2. uses household objects, and 3. is low on materials. The materials used may vary depending on what kind of knife you have. This may not make sense now  but it will later on in the instructable. Here is what I used and what you will probably use:

-CD (These can be bought very cheaply at stores if for some reason you don't have one)
-Lock Blade Pocket Knife (Not huge wooden BUCK knives but the metal/plastic ones like what  Gerber makes)(Your knife will not get damaged in any way)
-Sandpaper (I used a fine sandpaper but any kind works)
-Razor or EXACT O knife
-Fine tipped sharpie or pen
-Different sized screwdrivers (Either Philips or Standard depending on your knife)
-Allen Wrench or other tools that fit the screws on your knife
-Paint (Preferably gray or black spray paint)
-Various Drill bits
-Compound clippers (This is one of the items that you may not have and can be easily substituted)

Right now it may seem like this will be a hard thing to do but really you only use each of these things for a minute or two. Lets continue onto step 2 so that I can explain what is going to happen and how to prepare your pocket knife.

Step 2: Dismantling Your Lock Blade Pocket Knife

     By the end of this instructable you will have taken the actual blade off your knife and replaced it with a new one which we will create later. But Wait! Do not fret! This does not damage your knife in any way. When it is time to film you put on your fake blade. When you want to cut some stuff up then you put your real blade on. It is as easy as that.
     What you are going to do first is look to see if your knife has a clip that is used to attatch to your pants/pocket. If so, remove it (you will probably use the screw driver to do this). On ALL of my lock blades they have a side for a Allen wrench and a side for a standard screw driver. You are to take out the screw (stick the standard screwdriver on the one side and put the Allen wrench on the other and twist the Allen wrench counterclockwise). If yours has a different type of screw then try to find the correct tool for your knife. PLEASE be sure to be careful when removing the screw because after this is done the blade should be free of the knife. Be sure to keep track of all the pieces of your knife including the spacers and screw!
     You can put aside all the knife's pieces except for the blade itself. Handle with care and move onto step 3!

Step 3: Creating the Fake Blade for Your Knife

     Assuming that you are still intact after removing the blade of your knife you are going to get a blank CD (any kind works, if you don't have a blank one than use one that doesn't have anything too important on it, like your operating system). Make sure that your blade fits on the CD which shouldn't be a problem if it is 4 1/2 in. long or shorter. You are to outline your knife on the CD using either a fine tipped sharpie or pen. It is okay if the knife lays over the part of the CD with no labeling, just make sure it doesn't overlap the hole. (Look at pictures if you are confused). This outline is your boundaries of your knife. You can change the shape of your knife as long as it fits inside of the outline. After you are done, be sure to trace the hole on your knife onto the CD. Once you are done outlining and changing the shape of your knife, go over your line with a razor or exact o knife 3 or 4 times. This is to ensure your cut is fairly clean and acts as a guide for the clippers. The labeling will start to come off as you do this and that is a plus so that you don't have to peel it off later.
     Now that we have prepared the "blade" for cutting it is time to retrieve your clippers or whatever you are going to use to cut your blade out. Just follow along the lines you created and the cutting should be easier because of the exact o knife cuts. . Congratulations! If you have made it this far than you should have a piece of plastic that should look somewhat like a knife blade. Lets move on to step 4 for cleaning up our blade and cutting the hole!

Step 4: Cutting the Hole and Cleaning Up the Blade

     In order for this fake blade to function the same as the actual blade, there needs to be a hole in the blade so it can attach to the handle. To make the hole you will need to compare drill bits with the hole in the original blade a see which one fits the most snug. Once you found a good fit, insert into drill and drill the hole in your fake blade where you marked earlier. See if the knife's screw that attaches the blade to the handle fits in the hole you just made in the fake knife. If it still doesn't then get your exact o knife or razor and spin it around in the hole until the hole is large enough for the screw to fit.
     Now that you are done creating the hole it is time to clean up your amazing prop knife. Go around the edges with your knife or razor and try to smooth thing out. Add a little edge to the knife and a point to the tip. I sanded mine to get the excess labeling and plastic shreds off. It is important to make sure you sand it so that it can look as realistic as possible. Move onto the next step to hear about how to paint your knife blade.

Step 5: Painting the Knife

     This step is pretty straightforward and you can paint it however you would like. I am just going to share with you how I painted mine.

-Grab the knife with needle nose pliers
-Spray as much of the blade as I can
-Get wooden skewer and put it through the hole in the blade
-Stick one end of wooden skewer into a crack or under something heavy so the rest is dangling
-Spray the rest of the blade evenly
-Let dry

You can also use acrylic paint to paint a white/silver line across the edge of the blade to give it that sharp/realistic look. Heck, you could even add splotches of red paint and give it a "used" look...

Click over to the next step for how to finish up your fake knife and some tips as well!

Step 6: Finishing Up the Project and Some End Comments

     To finish up the knife simply reassemble the knife BUT with the fake blade. Your blade may be to loose even with the spacers in. My fix for this was to use a skinny and small washer as a spacer. To do this you simply look at your dremel bit that you used earlier and get the bit that is one size bigger. Drill into the washers center and the hole will get big enough for you to use it as a spacer!

How can I use this into a movie?
     Other than the obvious way of cutting people with it, there are other ways to use this knife in movies. Since this prop knife is so easy to construct, it is easy to make multiple blades. You can cut the top off of one with the clippers and repaint. Maybe even add blood! When it comes time to the stabbing scene, switch knives when the camera changes with the half a knife and it will actually look like the knife is inside of its victim.
     Thanks for even looking at this instructable! This was my first one and definitely won't be my last! Please comment below and post pictures of your own fake prop knives as well! If you have any issues as well just send me a message and I am almost sure I will have a solution.  See you around Instructables!




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    14 Discussions


    8 years ago on Introduction

    Nice write up. My only concern is how 'safe' this really is. This knife may break easily at the bolster (since it's the thinnest), but I bet in a thrusting motion it would easily stab someone. I agree that it's safer than metal, but can still be very dangerous. Think of any prison documentary you've seen, it doesn't take much to make an effective weapon. Do what the pros do - film a real knife in close shots, and switch to a safer knife in action scenes. It does look pretty convincing though.

    1 reply

    8 years ago on Step 6

    Good instructable, but shouldn't a prop knife be like not harmful and be able to look like it stabbed a person without stabbing them?

    4 replies

    Reply 8 years ago on Introduction

    It is actually all in the camera shots. Unfortunately there is really no prop knife you can create that makes it look as if you have stabbed something. You can however create a latex wound where the person gets stabbed. You can also cut the knife in half and when you switch camera shots have the half knife inserted into the latex wound. You can really just experiment with different ways of making it look realistic. But thank you for your feedback and hope to publish more "prop" instructables soon! (I am working on a few grenade props at the moment)

    nail facespark2FLAME

    Reply 8 years ago on Introduction

    hey, couldnt you like make it a plastic spring loaded one? like it gets pushed into the handle when you "stab" them?

    spark2FLAMEnail face

    Reply 8 years ago on Introduction

    Ya, I'm sure that if you get a cheap switchblade from a flea market or something but take out the locking mechanism then that would work as well.


    Reply 6 years ago on Step 6

    yeah, and it would be possible (though difficult) to make it deposit some fake blood when it stabs


    Reply 7 years ago on Introduction

    Gerber is a knife/multitool company,
    you can get gerber multitools in camping shops and you can get their knives of the internet (i.e. amazone, ebay)


    8 years ago on Step 6

    hey do you want to see a reel prop knife go to / and please leave a comment


    8 years ago on Introduction

    That is so AWESOME!!!!!!! Thanks so much! I've needed a way to film with knives!


    8 years ago on Step 3

    Or you could use a transparent CD protector ( It's the one on the top of a box of writable cd's) ;)


    8 years ago on Step 6

    pretty cool instructable good job very nice cutting i will be making one of these!