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Kodiac
October 20, 1998, 03:18 PM
I know this is not a gun topic, but any one have any suggestions for a Wanna be knife maker?

Paul
October 20, 1998, 06:15 PM
If you know someone who works at a machine shop, see if you can get their old hacksaw blades. (The ones from the big motorized saws.) I have made a couple of knives out of these and (if tempered correctly) they are easily sharpened yet hold a good edge. I have a friend who swears by old automobile leaf springs.
Whatever you make it out of, the most important step is the hardening/ tempering. Don't skimp on this, do it right!
Good luck!
Paul

Kodiac
October 20, 1998, 10:30 PM
Thanks Paul... I heard about the leaf springs... Saw blade? Makes sense.

Tempering is so critical - What is the best way to do this - and how do you know when you've got it right, and when to stop?

I have great blade designs... but now I have to make them great blades.

Paul
October 21, 1998, 06:38 PM
Hey Kodiak,
Now, this isn't exactly high tech but the way we used to do them is heat them EVENLY to a bright cherry red, douse them in oil (leave them in until they are cool) and then heat them just to a dark red and bury them in fine sand until completely cooled.
The secret is to cool them SLOWLY. Getting the color (temp) right is something that comes with practice. One guy I knew used to pack his in clay, then wrap it in thin sheet steel and bake it for about three days. I didn't like this method for blades as they come out so hard as to be VERY difficult to sharpen. It does however, work great for hardening new frizzens for flint locks.
I'm sure there is a newfangled method out there that will be easier, but I doubt the results will beat the old method. Also, there's really nothing like knowing you can harden steel with just a torch, a can of oil, and some sand.
Good luck, and keep me posted on the progress.
Paul

Mac Scott
October 22, 1998, 09:14 AM
One other method to consider, regarding heating steel to a certain temperature, is "Tempilaq." This stuff is painted on the surface of the workpiece where it dries hard like paint. When the piece is heated (by whatever means) and reaches the desired temperature, the Tempilaq immediately melts, indicating a time to begin the cooling down process.

It's sold by Brownells and comes in a whole bunch of different temperature settings or grades. You just have to figure out how hot the particular steel you're working with has to get for good effect.

----Mac Scott

Kodiac
October 22, 1998, 03:59 PM
THANK YOU, MAC!
You Da man!
I will try it next week whe I will try to get some actual Forge Time in at an old fasioned smithy.


Oh, Hey - when your treating the blade, instead of sand , can't you use crushed coals? I heard this will increase the steels carbon content with repeated use. True or false?

[This message has been edited by Kodiac (edited 10-23-98).]

.
October 27, 1998, 03:38 PM
Kodiac,

On the northwest edge of Richmond (Glen Allen area) there is a park with an old Antebellum working farm. There is a 'Smith that uses the onsite bellows and coke furnace to make period pieces to maintain the place. Check with him on the practical applications of the hand forge. I recall that he has made a few blades in his spare time, also.

It would also behoove you to check the optimum "heat ramp" and cooling rate for your steel in a a good metallurgy reference, as this affects the formation of certain metaphase crystals and their relative concentration is a key factor in the quality of the final product.

Consider heating and cooling your shaped, ground, and previously oil quenched blade in a 2-3 inch diameter steel pipe. The pipe should have screw-on steel caps at both ends, one of which should have the smallest hole that you can drill through it. The hole will allow the expanding internal gases to exit sedately (ensure you fellow LE buds understand that you're making a thermal stabilization chamber, not a pipe bomb http://www.thefiringline.com/ubb/smile.gif ). Completely surround and isolate the blade from the walls and ends by packing it with finely ground bone (dry) or fine sand with a high alumina silicate content. Heat the assembly to the desired temperature and maintain that temp for several hours to ensure the homogeneous distribution of heat within the chamber. Allow it to cool for a couple of days, preferably in the closed furnace or oven where it was heated. If not left there, be sure that it is not placed on any thing that would create a heat sink or otherwise cause a cooling differential around the chamber surfaces. If you use the bone, the result will be a very hard but not brittle steel that will withstand shock well and has the added benefit of case-hardened coloring.

[This message has been edited by Mykl (edited 10-27-98).]

Kodiac
October 27, 1998, 04:52 PM
So... It goes like this:
I cheat the forge and have a blade design milled on a CNC machine. I bake it in Mykls pipe bomb oven ( thanks mykl http://www.thefiringline.com/ubb/smile.gif ) And then to finish the process... Cryogenicly treat the blade... Freezing it for 3 days in -300 degrees.
Kinda like cheating as this stuff is all pretty hands off... What do ya think?

4V50
October 27, 1998, 07:56 PM
The NRA has a knife making class which is operated out of their gunsmithing school in Susanville, CA. It's about 90 miles NW of Reno. The school is pretty good and if you're a CA resident, fairly inexpensive ($33). You can also bring your rusty gun up there, sandblast or polish it and blue it or parkerize it during your lunch hour.

Absent visiting CA, go to a blackpowder sutler and he'll have all the raw materials and books. If you can't find a sutler, attend a black powder rendezvous in your area. You'll find a lot of guys make their own knives and they'll be happy to share their insights with you.

Rich Lucibella
October 28, 1998, 11:25 AM
An excellent treatise on heat treating steel for knives may be found at http://www.mdenterprise.com/heat.htm

Author is Kevin McClung of Mad Dog Knives.
Rich

Kodiac
October 28, 1998, 11:49 AM
Thanks Rich... That was most insitefull.

Now I believe the process I will go with is this...
I will design the blade I want and blue print it. Then send that to a maker that knows what the heck that was all about.

Thank God I work for the makers of ADVIL and can have all I want... I need some now.