Knives

So, I was bored this afternoon. Instead of playing video games, I decided to make a knife, something I've wanted to do for a while. I hardened it with charcoal in the front yard, and I tempered it in moms oven. All thats left is a little more cleaning up, and putting on the handle. I'll post pics when finished.

Does anybody else make knives here? I know you people have some weird talents...

I cured boredom the other day by finding 3 push mowers put out for garbage. inside of 2 days i have 2 of the 3 working perfectly (starts on first pull) and cutting evenly. gonna keep one and sell another to a relative's kid who wants to cut lawns for summer cash.

Interesting that your making knives, did you learn about phase diagrams and the different crystal structures in order to properly heat treat your steel? (I am a materials engineering student and if the answer is yes, color me impressed that someone your age has learned that!)

I have always wanted to try that, but life interferes sometimes. I have one that my grandfather made forever and a day ago. He cut the blade out of an old saw blade so he wouldn't have to temper it. The blade is sandwiched between two pieces of wood and riveted with brass rivets. It's a cool keepsake. Probably 50+ years old. He used to use it to cut vegetables in the fields. I remember it riding on the dash of his truck when I was a small boy. I'll pass it down to my son one day, and hopefully it will stay around for a long time to come. Too bad so few people make things today that will be considered valuable in a hundred years.

Well, kind of. I understand how it works and what is happening when the steel is treated, but I didn't look at diagrams to figure out exactly what temperatures to use. I read a knife making website how-to on heat treating to figure out exactly how to do it.

Why does steel loose its magnetism when heated red hot?

Apexcarver wrote: ...color me impressed that someone your age has learned that!)

Ouch!!

i once made a spear out of bamboo

I broke apart a rock and used it to cut thrue a fallen tree. My hands hurt afterwards

I Have flint napped a knife out of stone, that's a long and boring process, until you make a mistake and ruin the whole thing in one swing

I plan to go all "The Hunted" and actually design and hammer out my own, that and a sword.

Cool. Looking forward to pics.

I've got a friend who makes knives. He's a big guy, heavy-set, and always unshaven. I think when he mentions to people that he makes knives, it must creep them out slightly. Just seems a bit of a serial-killer hobby. (He's a nice guy, though. )

I'd like to have a crack at knife making myself. The closest I've come is the trowel I made when I was 13. Mum still uses it in her garden.

Tommy Suddard wrote: Well, kind of. I understand how it works and what is happening when the steel is treated, but I didn't look at diagrams to figure out exactly what temperatures to use. I read a knife making website how-to on heat treating to figure out exactly how to do it. Why does steel loose its magnetism when heated red hot?

Basically due to the thermal energy making the atoms too kinetically excited to remain pointed in one direction for long enough for the attractive forces to be effective. For a better scoop look up "Curie point".

Dont feel bad for not knowing the phase diagram information. I learned it as a part of a 300 level college engineering course If your interested, I can review my text and probly find the diagrams online and post up some of the basics tomorrow so you can see whats really happening with the metals. (It is really good stuff to learn about if your interested in fabrication for strength applications.) (If you still have "science fair" type stuff it would also make a great topic)

If you really want to learn the stuff I can give you the ISBN of my Materials Manufacturing text. It can be a bit heady, but its the best way to learn.

My friend used to have a small engine repair shop, and we made heavy duty machetes out of worn out lawn mower blades. Good steel for free. We'd make handles out of busted axe handles, and rivets from large guage copper wire. They were pretty crude, but we had a good time doing it. Good luck with your project!

http://en.wikipedia.org/wiki/Japanese_sword

If you're bored and interested in metallurgy, look up how they made Samurai swords. The apprenticship to learn is 30 years.

If you heat metal and bang it out flat and then fold it over onto itself, that's one fold. This material is folded over 400 times. If it's folded in the same direction every time, it's called ____, but folding it 90' each time has a different name. Each process generates different grain boundries and patterns in the metal that can be seen with the naked eye on the finished surface.

The blade has to be strong to hold an edge, but that usually means very brittle material, so they make a "V" of hard material and put a slab of softer matrerial in the center, fold the two together. Upon heat treating the difference in materials can be seen as a greyish line. The line can be razor straight or look like a row of clouds on the horizon. (called clouds & rain, Japanese for orgasm).

Heat treating is different, sometimes quenched in virgin's urine; can you say Salt Quench? Sometimes five enemies are lined up front to back and the blade is thrust through all of them and allowed to cool on station. Brutal but effective results. The sharpeneing is usually done by a Shinto priest. An apprentice will work for four to six years making the wooden scabbard before he is ever allowed near a knife.

Under the wrapped handle of the blade is carved the blade's history, family lineage etc. I find the metal more interesting.

Google "Materials Handbook", if you know the metal you started with this may help in time and temperatures for specific results.

Dan

Materials Technician

Curious.

Look up a book called "The Art of the Japanese Sword" for more on what Dan said. I have made a few knives out of old files. Grind to shape, polish, and put a handle on it. Very brittle but good for letter openers and work in the kitchen.

I've made knives out of steel and stone. All three of us (me, wife and son) have knapping kits and have made stone knives, axes, arrowheads and such.

Ok, I got around to taking a picture. This is right after tempering, before final sanding and polishing. I picked up the wood for the handle a few minutes ago, Red Oak.

What do you think?

That looks like a folding hunter that doesn't fold.

Well done.

Nice I wish I was as cool as tommy (now and when I was a kid) LOL.

Is Mom going to need to build another patio?

Ok, I put the handle on, and the varnish is drying now. How do I keep the blade from rusting?

I'd say, "wipe the blood off on your shirt before it has a chance to oxidize the steel." but that's not what you want to hear.

Figure out how to Parkerize it? http://en.wikipedia.org/wiki/Parkerize

What kind of metal is it and where did it come from? Sounds like a cool project.

Tommy Suddard wrote: I hardened it with charcoal in the front yard, and I tempered it in moms oven.

Knowing Margie, she's probably more angry about the missed apostrophe than the fact that her oven was used for this

Tommy Suddard wrote: Ok, I put the handle on, and the varnish is drying now. How do I keep the blade from rusting?

Marine grease is your only hope. Steel rusts pretty quick unless it's Stainless, and even then...

thedude wrote: What kind of metal is it and where did it come from? Sounds like a cool project.

Some kind of carbon steel I found in the shop.

If you clean it well and store it away from moisture, you shouldn't have much problem with rust.

In other words, your next cool project is a one-off custom leather sheath. How are you with rawhide?