Instructables
Picture of Home-made copper knife
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I recently made this knife out of a copper tube. It's work hardened and keeps a pretty nice edge on it, works well as a throwing knife. To get the shine to stay on it, I polished it with coarse sandpaper, then fine, then used 2 different rubbing compounds to get the scratches off, then did 3 coats of clear coat lacquer.
The handle is made out of pine I believe, or some other common wood, I'm not too sure on that. But I used a 1x1 inch piece of the wood, and used about .3inches of wood on each side of the blade handle. The handle is coated in a pecan color wood stain with a smooth finish in it.
The blade is actually soft 1/2" copper tubing, about 10.5" of it. I work hardened it with a ball-peen hammer so it flexes, but doesnt really bend. The blade length is 6", while the handle is 4", for a total length of 10". And yes, the blade is full tang, if you havent already figured that out.
I forgot to take pictures along the way, so I snapped a few pics of the finished product with my camera phone, explaining the moderate quality on them.
All in all, its the best knife out of the 2 I have made (not much to compare to, I'm planning on making more) and I probably could have used a nicer looking thing to bind the handles together than gorilla glue, but it works.

why copper? was it just because it looked cool? because copper is getting pretty expensive. i actually like the look of the knife and every thing though. very rough and homemade looking, just what i like.
_Scratch_ (author)  ducktape.mac3 years ago
Because I don't have the nessacery tools to smith steel, and I had some copper laying around. I got that 10foot spool of tubing for 12$, which is enough to make a good dozen knives.
is it very strong? it seems like copper would bend easily.
_Scratch_ (author)  ducktape.mac3 years ago
Thats what the work hardening helps with, it still bends, but it flexes about 3 inches and returns back to its place, its pretty durable. I can throw it from 25 feet into a box, and even if it hits the side of the blade, it wont bend.
nice. i'll have to make one someday. i don't have the ideal tools to be working with steel or anything like that. and the pipe would be the perfect shape too.
_Scratch_ (author)  ducktape.mac3 years ago
Yea, I was hoping to make a forge this summer, but I'm not sure how much spare money I'll have to do that, so that may be put off until next summer. If I do manage to make one though, I'll make sure to get an 'ible up on it, and make some steel or bronze knives.
funny, i was also thinking about making a forge over the summer as well. but just like you, i'm short on money. one thing that we could do without a forge is use the galvanized metal strips that they have at lowes. they are pretty cheap, and whenever i go to lowes i normally pick one up just to swing around the store like a sword or something. but i was thinking last night that they might make a good knife if i cut one up and sharpened it. but how did you attach your handle?
_Scratch_ (author)  ducktape.mac3 years ago
I looked into the toxicity a bit more, and the reaction of zinc fumes with oxygen creates zinc oxide, which isnt carcinogenic or very toxic, but it will induce severe flu-like symptoms, but not cause any long term damage. I would still stay away from it.
Also, the way I attached the handle was take the 2 pieces of wood, and put a small line of gorilla glue on each one, then stuck them on the handle part of the copper, and clamped them for about 5 hours. every 40min or so you should clean up where it starts to drip, due to the expansion of the glue.
Oddly enough, the glue is incredibly strong and I havent had the blade move even a millimeter since the handle was attached. so it works pretty well.
If you are still trying to make a forge you should try a fire pit first. Safer than gas and wood or charcoal withsome air glow is enough to melt soda cans in like 10seconds once its going. I used a hair dryer ( semi melted hehe) and forged 3 steel knives and made a few aluminum ingots for rings. Wood andcharcoal burn hot andlong but create a little mess after words. And when ur done u need a looong shower or ull smell like a smoke bomb went off on u.
yeah gorilla glue is incredibly strong. now, about the galvanization, would that stuff that you get at lowes for welding be galvanized? because i used some today and i didn't smell anything out of the ordinary. i'm pretty sure its not. i think i mentioned it being galvanized because they had galvanized sheets on the website and i thought everything was.
_Scratch_ (author)  ducktape.mac3 years ago
I dont think welding steel is galvanized, usually you tell because it has that distinct gray triangle pattern.
okay, i didn't see any of that on the metal. the knife turned out good though. just very hard to sharpen.
If you don't have a forge, you can make a basic one with one of those small metal patio braziers. Leaf blowers make great forge pumps, just rig it so it doesn't melt.
_Scratch_ (author)  bobwantzanapple3 years ago
Wouldn't a leaf blower be kind of.... inefficient? And insanely loud?? Or do you mean a electric one?
Electric. You should use some of high- temperature resistant tubing to direct the air into your fire. If it is blowing too hard, you could try a lower-powered device, or use something to divert some of the air.
sounds good.
_Scratch_ (author)  _Scratch_3 years ago
Also, I'm gonna try my hand at making some pattern-welded steel when i build that.
Steel isent toohard to wwork with. In my insructable i take a steel dresser base and make a durable knife. Tested it on fresh pumpkin...... hehe little to no force and i cut to the base ):p
curvy772 years ago
I like the design, and it shines like a new penny!! However copperis not the best material for knives or really any bladed weapon, cept axes, because its a soft metal. Constant reforging make it less wanted than iron.
wolf9963 years ago
I made a spear like that
wolf996 wolf9963 years ago
Here's My Cheap Copper Spear Instructable:http://www.instructables.com/id/Gettin-Started/
Nice knife but when you made it did you fold the copper pipe in half??
Nope, I cut a line down the middle with tin snips then folded that out. I then hammered that to make it flat, no folding, only cutting then spreading it out.