Instructables
Make A Two Bladed Folding Pocket Knife Made From PVC & Hacksaw Blade.
 
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Step 1: Parts and tools needed

To make a Two Bladed Folding Pocket Knife you will need 1/2 " pop rivet, 2 washers, and "thin wall" Class 200 PVC . Time to make about 1/2 hour. Tools needed are hack saw, pop rivet gun, stove, sand paper, grinder (you can use a sharping stone rather than a grinder but it takes longer).

Step 2: Make blade blanks

Flex hacksaw blade back and forth to brake off the ends for blades. I leave one as a saw but you could make it a knife, screwdriver or other tools. You can make 3, 4 or more blades if you want.

Step 3: PVC

I used class 200 PVC 1" split into 1/3 but you can also use a whole section of PVC (heat and smash; then cut length ways to make your handle)

Step 4: Grind blades

Grind the teeth off of one of the blades, sharpen and shape.

Step 5: Keep them cool

When grinding never let your blades get so hot you can not touch. If they get too hot them they will not hold an edge. Cool often by dunking in a can of water.

Step 6: Soften the PVC

Heat PVC over your stove. Do not scorch. Keep it moving always. You should be able to just barly handle it by hand. When soft and flexable quickly insert your two blades and press it into shape till it cools.

Step 7: Shape PVC

Use a hot pad to press the soft and hot PVC to make your handle. Make sure you first insert the blades so that the handle will not be too tight.

Step 8: Blades and handle.

Blades and handle.

Step 9: Smooth handle

Sand and round the edges of the PVC. also sand out a finger slot to grab the blades when folded.

Step 10: Assemble blades into handle

Drill hole same diameter as the rivet. Place the hole 5/8 " from the end of your handle so that when blades are open the back of blades are supported by the handle. See the two washers on the rivet. The PVC is not stiff enough without the washers.
kalebpolley24 days ago
Schmidty162 years ago
pretty cool r u going to put ur name into the side contact me back
Thats is awesome. sadly i dont have all the tools to make it :(
heathbar642 years ago
Seems to me like the pvc would wear and let the blades wobble around and fall shut. I wonder if you could use one of those spring washers between the blades. that seems like it would keep them the right tightness even when the thing wears a bit.
Clever!
Grimmy Grim2 years ago
Thank you, I appreciate these sorts of projects and the nice layout that is step by step.
ghost9992 years ago
awsome
dude
The Mariner3 years ago
If you arrange the saw blade so that it cuts on the pull stroke, rather than the push stroke like normal, it'll help prevent the blade from breaking.
hey yeah....like a japanese hand saw!
ilpug3 years ago
seems pretty awesome, although i have tried making knives from hacksaw blades and they always snap. i would try this, but use old reciprocating saw blades.
gary.9183 years ago
looks good. the blades will be a little brittle, but should work. well done
extraordinarily good!
(YOUR N4 years ago
G567 MY NEW CODE NAME
TALLJ294 years ago
looks pretty cool and easy. Might have to try it when i get some time!
skimmo4 years ago
have you tryed meccano for the handle?
ajjardin4 years ago
Nice Instructions. very clear and precise. 2 bladed folding knife is very handy. i was thnking of making one with 2 saw blades. thanks for sharing

Spring Assisted Knives
I like it. Nice work. I make mini neck knives out of hacksaw blades as well.
I use a simpler technique they are part of a necklace kit I make.
But I really like this. These are up to $5 and you just made one for free basically.

Strong work keep it up. Peace

So how do you make the knife lock.
i made a few of these knives today i made one like the one in the picture but with a sharp point rather than a rounded one i also made a single bladed version (also sharp pointed) and then i made a folding fillet knife but with the same materials! i not only made the point on the blade but i polished the blade with a belt sander and then fie sand paper and it looks really professional! thank you so much for the idea by the way!
tahirhh5 years ago
if you have access to a laser cutter, you can make the sided bits on 2D Design
ajk975 years ago
Does the knife stay open or is it loose and fall back into the handle? Thanks and great Instructable.
Murdok7 years ago
How do you pop-rivet? I need a substitute, any ideas?
Matin (author)  Murdok7 years ago
Pop-rivets are small metal rivets that require a "Pop-rivet tool" to make it work. You can get both at most hardware stores. You can also use regular copper rivets which use a hammer to mash the protruding end.
how much does a pop rivet gun cost
Use a bolt?
berky937 years ago
I'm in the process of making a metal version of one of these, but I realized that the knives will dull when they contact the metal over and over. What can I use to cusion them? I was thining of this rubber coating stuff, but I don't know what it is called and where to get it. help please?!
y dont u use inner tube??
er....try a little bit of papre, just folded and pushed into the handle, if that doesn't work try and get some thin leather or a piece of the sealing rubber off waterproof torches. or even an elastic band poked into the bit where the knife'd touch the metal
take a swiss and cut off all but 2 blades
or just take a swiss
i know i should leave you alone, but i just realised as i got home from college that if you use copper as the metal, the steel'd not be damaged cos the copper's softer
xenongamer6 years ago
good. I might try this, seeing as my other knife got... broken... while i was trying to modify it. yeah, who knew that tungsten could destroy half the house.
i like the style i made one sorta like it expet was an otf swicth
and i mean the par were u bind the pvc
its realy cool but how do u get it to fold
pumpkinman6 years ago
extremly nice instructable, i used boilin water to bend my pvc pipe and that did not work so well. do you have any idea of what to make of the rest of the hack saw blade?
Lance Mt.6 years ago
Boiled water. It does the job rather than a naked flame with toxic fumes.. Other than that, It's super sweeeet (making 1 now.)
nfsaggese6 years ago
Do you know how to make it a locking blade?
very cool.. if i had more time, i would totally try this!
DIYerr6 years ago
This is an exellent instructable. I am using the pvc material and method described here as a substitute to a kydex sheath for a very small neck knife I just started making.
bowmaster6 years ago
I am going to make a balisong
nice instructable, but when you melt the plastic, be careful, the fumes coming off of it could kill you...
stone34087 years ago
I diagree this could be very useful if produced without the knife (that could be a problem). Think screwdriver shape, lock pick, wire bending notch, or awl along wih the saw. I would even consider using jig saw blades, less grinding I will have to destroy some saw blades over this one. I wonder if you could wrap that all up in one sawsall blade sheath it and make it wallet worth.
like this...
tool.JPG
cool
sk8erdude6 years ago
Awesome!!! after seeing your other knife instructable i came up with the exact same idea but i didn't know what to use for a casinggreat instructable i rate 5 star! thx 4 posting -sk8erdude
omzig186 years ago
congratulations you have been added to stumble upon!
X_D_3_M_17 years ago
hey yo this was on primitive ways.com !
yeh!
Matin (author)  X_D_3_M_17 years ago
same maker in both
Loveofchaos7 years ago
I see a homemade pocket lockpicker in my mind...
LOVE IT :)
nice idea how well does the top part of the handle stand up to the pressure of the back bottom of the blade hitting it whenever you cut something?
Matin (author)  garrettmikesmith7 years ago
Holds up well. Would not recommend for heavy carving however.
PaulTozzi7 years ago
could you do this with more blades?
Matin (author)  PaulTozzi7 years ago
Sure. How about adding a finger nail file (you could buy a metal file from a drug store; grind it down to fit, drill a hole and pop rivet it in); or a locking device for the sharp blades and or screwdrivers etc....
locofocos7 years ago
Here's an idea I had for a safely latch. You get only one blade, but cut a weird shape in it and a corresponding piece with the same shape so it presses against it until it locks. (just look at any other knife with a safety- you'll see what I'm talking about.)
knife diagram.bmp
This is cool but you could go to walmart and get a knife for about 10 dollars.But if you design this knife handle you could make it a very nice gift for fathers day or something like that.Then it would be worth about 20 dollars
Ben.land1017 years ago
this isnt exactly the safest pocketknife you kould make but its prety cool.
Think7 years ago
great one i need to do this, five stars
p1pe7 years ago
This is really nice. I work with Styrofoam and urethane insulation and use hack saw blades all the time -- and a knife to cut the filament tape!
Sgt.Waffles7 years ago
Thats cool.
macman5557 years ago
Wow, I am just speachless. I love to see these kind of things.I am definentley going to go make this.
coooooooooooooooooooooooooooooooooooool
JMB7 years ago
looks unsafe to make but besides that its good
gobob29 JMB7 years ago
i have a movie studeo (not perfeshinal but still) callded JMB studeos
littlemog927 years ago
i made one but with wood and it has a lockpick instead of a saw
Wade Tarzia7 years ago
Very interesting, I like this, as well as your folding saw. I have made small cheapy backpacking-type saws by wrapping epoxy-soaked cord to make a handle around standard replacement saw blades, but then you need a sheath. This is better.
for the riting thing i guess a screw and bolt would work or one of thoes hammer down rivits i "borrow" from school would work. for this im thinking lockpicks, the ideas are endless mwahahahaha. off to fo smite 1st years later
jackfr0st7 years ago
twould be so sweet if i could do it witout a riveter gun and if it locked for safety any suggestions
zofo3007 years ago
thats a pretty good knife for a DIY pocket knife
Spanky7 years ago
I don't think this is any less safe than an ordinary pocket knife - In fact I think this is a great instructable - Bravo matin
jtobako7 years ago
with the rounded back to the blades, it's very safe-better than some of the pocket knives i have where the tip of the blade sticks out over the handle area when closed. two sugestions. one, the knife blade has to be short or it will twist when you use is because it is so thin. two, heat up the corner of the handle where the blades rest when open and dent it is slightly. this will give a better angle on the blade when you try to use it. three, watch what type of hacksaw blade you use. bi-metalic blades have little more than the space of the teeth as hard metal. the shape of the blade looks like you realize this, but it's something to point out. watch which way the teeth point on the saw. you will be safer if it's a pull saw rather than a push saw. if the pivot was moved away from the end, you could have a T-shaped handle for a better sawing grip.
Kiteman7 years ago
Sorry, but that looks seriously unsafe, just itching to take a lump out of you as soon as it catches or sticks on whatever you're cutting. Plus, if a (UK) policeman found you in possession of one of these, I think it would take some time to explain away.
[Removed by author]
ddsn7 years ago
Err...that looks very, VERY unsafe...
I don't think it's 2x-very unsafe, but a knife that you can open with one hand and that locks open for safety is a thing of beauty. I'd love to see an instructable like that, even if it's cheaper to go buy one. Some things are just worth doing.