Knife Making

[bow101]

So I did a lot of research on Kinfe making, mostly from files and old saw blades.  The question I have is observing these guys cutting out blades from circular saw blades.  THey just go for it. I know the Blades are allready tempered to a point. Is it necessary to temper it after it has been cut out and shaped.
It would still keep an edge without the post heat treating....Correct..?

[madcrow]

most of the blades i have tested were rockwell hardness 35.  It will take an edge but will dull quicker than one with rh 55.  If you can cut and shape a file (rh60) without messing up the temper it will make a fine knife.  Also industrial bandsaw blades are heated and tempered and make great small knives.

[jimdavis]

the file will be brittle if used with out heat treating it; also the newer files are only case hardened meaning made of lower grade steel I would put your file in the fire and bring the heat up until non magnetic  the let it cool make your knife the re-heat it quench it in oil (I use leftover peanut oil from turkey cooking) temper it in your cook stove 400* for a couple of hours

[bow101]

most of the blades i have tested were rockwell hardness 35.  It will take an edge but will dull quicker than one with rh 55.  If you can cut and shape a file (rh60) without messing up the temper it will make a fine knife.  Also industrial bandsaw blades are heated and tempered and make great small knives.

How easy is it to drill the handle without annealing the file first..? ..Not..!!

[madcrow]

That would depend a lot on drill speed and bit quality.  I don't have a problem drilling them.  Slower speed and high quality bits will get you going.

[KHalverson]

some good points made by all here
ive done knives from small circular saw blades with no heat treat and found them to be a bit soft for holding an edge for very long
ive also done the raw file knives by grinding them to shape and keeping them cool
and found em to be a bit brittle  i.e needed a temper cycle to draw back the hardness a touch
now a few years later and a few kniives later would i do either again
no.
in my oppinion proper heat treat,temper and edge geometry seperate a decent knife from a great knife
i guess the bottom line is its different strokes for different folks
and everyone has to start some where
 the most inportant thing to me is seeing new knife makers have fun
and if ya see a guy doing something that youd like to learn to do ask questions
Kevin

[bow101]

Metal work is just as much fun as woodwork, or the other way around. Does not matter it's all GOOD...!!
So exactly what do you guys recommend for steel grade in metal, and where do you buy it..!

[bigpapa]

The hardest thing for a begining knife maker to understand is the difference between tempering and heat treating. One sets your hardness and the other draws your hardness. All sorts of steel take to it differently, you can get most of your cheapest usable steel from the scrap yard. Decide what use your blade will have and select a piece of steel that would see the same stresses. Like a lead spring will make a good blade, but not a very good chisel or punch.

[KHalverson]

1080 steel is pretty easy to work with in heat treating and makes a great blade
it can be purchased from texas knife or one of the other knife supply stores
Kevin

[Cardboard_Duck]

I just built this forge to heat treat -


two 9.5x4.5x2.5 soft fire brick, coated with satanite and ITC 100

a toaster over to temper and some 1080 from admiral steel