Only because i just seen the topic.
Seriously you can make knives and spend next to nothing. Heck some times it in fact wont cost you a dime.
If you got a car you got your cooling fluid to temper with. If you got a oven you got your heat treat oven. Few files of vaiour corseness. Youll need to sacrafice at least one large file made by say nicolson(sp?) or miller. I bet theres a old worn out one in your garage.
To use a file as a knife blade you need to soften that hard sucker up. So see that first heating step in the link MSCantrell provided in the qouted post here? Well instead of quenchign it set it aside and take a break while you wait for it to cool down to the air tempreture. Now take a decent file and see if you can cut in to the one that just finished cooling. If so find your self a nice vise or c clamp and start profileing the blade to get the basic shape you want. I sugest a warncliff , spear point or drop point. The files own taper lends it self to a spear point or drop point pretty well and a warn cliff as well. Once you get the shape you like change how you have the blade clamped.
For the edge "grind" you want the blade flat with the edge ither just off the work surface or right at the edge of it.
File on the blade from edge to spine removeing very little meat up towards the spine. work the edge grind till you file to half the files thickness Well almost you want say 1/32 to 1/16 inch flat showing when both sides are filed explain why in a few minutes). Now flip it over and repeat. All the file marks from the file you started out with should be gone by now.
Look at both sides and make sure that both grinds go back the same distance towards your future tang. If not true it up and finish off the file work on the spine and flats of the blade.
Once all your file working is done redo your fire pit getting it nice and hot again. Heat the blade in the fire till cherry red and non magnetic and hold at this tempreture for a minute or 2 after. Now quench in that old motor oild from the oil change you did earlyer. Thee reason you did not take your grind t a edge is on quenching it would warp or simply chip off.
<ake sure to clean off the oil thats on the blade less you want the firedepartment called by your neighbors who mistake the billowign smoke as a house fire hehe
After quenching go fire up your house hold oven to i beleive its 450 degrees. Once preheated place your blade inside for 45 minutes. After 45 minutes remove fromt he oven and allow to cool to room tepreture. Youd blade will be this pretty bronze brown color. Now put back in the oven for another 45 minutes.
Time for some more filing. This time close up the edge grind so there is no visable flat area along the edge.
After that its just a matter of polishing puttng a handle on it and sharpening.
I just finished up a new knife like this my self came out nice except one little problem on the way to the stove i dropped the blade on to the hard cement patio at the foot of the stair. The blade is now in tiny little bitty peices. It was a nice drop point bowie made frma 2 inch wide 1/8 inch thick niller and sons file. over all length just shy of 17 inches. It sucked but such is life. If i could have gotten it tempered it have posted pics of it. But as it is they chunks are like 1.4 to 1 inch and no hope of even putting it togather for a pic.
I did get to see the quality of the steel though. No bubbles in the file and it was uniform silver in color. None of the sandy texture you see in cheap files when you snap them. This was a miller bors 0/0 bastard cut file. So if you find a flemarket special like that for a buck snag it it can make a good knife blade just treat it like its a million dolor ming vase when your heading to the oven
