For A Forged Blade What Would Be A Good Steel.

[markknx]

I have built a forge and will be just playing with some projects. as far as for knife making I have heard o1 used a lot when machining knives, but would it be good for forging? I have also hear old files but what would I order if I ordered the steel on line. would 4140 work? does not need to be top shelf but usable.
Mark

 

[Franko]

I've heard of people forging knives out of old trailer leaf springs.

 

[T Bredehoft]

Years ago an acquaintance of mine used O1 steel. He bought 1/8 by 2" by 36", bandsawed the form, ground to near finish, heat treated them, (quenched in hot oil) and polished them for finish. He liked to use an epoxy handle covered with a turtle's tail skin.

 

[RJSakowski]

O1 can be forged as well as machined. Leaf springs are not intended to be hard, just "springy". They are often medium carbon steel and may not achieve the desired hardness. I have no direct experience with 4140 but it appears that it is a medium carbon steel as well and and has a maximum hardness of HRc 60. If you can find them, I would guess that old time buggy or wagon springs might have a higher carbon content. Files should work. Just be sure to grind away the teeth prior to forging. W1 steel is forged as well and can obtain a slightly higher hardness than O1.

McMaster Carr carries a variety of steels in bar form. Here is a table of properties for the steels they carry: http://www.mcmaster.com/#standard-steel-sheets/=xbp8qf
If you are going to use a steel of unknown pedigree, it would be wise to run a piece through a hardness test before investing the time and effort in making the knife.

 

[markknx]

RJ this is why I was asking about known steels. I have other steels, like RR spikes to learn how to shape thinks on. I just don't want to take time to make a blade and have it be trash or just a show piece. Thanks for the help to all that posted.
Mark

 

[RJSakowski]

RJ this is why I was asking about known steels. I have other steels, like RR spikes to learn how to shape thinks on. I just don't want to take time to make a blade and have it be trash or just a show piece. Thanks for the help to all that posted.
Mark

In that case, I would go with O1 or W1. Both are commonly used for cutting tools and the hardening/tempering are straightforward.

 

[markknx]

Thanks I just wasn't sure if forging them would spoil the steel. I have since read that that you also have you take care to not forge it below 1600 F for O-1.
Mark

 

[chuck]

The machinery hand book, at least mine does, has a section on what different steels are, gives the asme designation of drive shafts, leaf springs, torsion bars etc of the parts of heavy and light machinery.
I have made things from automobile leaf springs, old one piece chainsaw bars and lawnmower blades quenching in water and heating to a yellow for tempering. More specifically, roughly tempering, ,,,Not necessarily hammer forged, but cut to shape with oxy acetylene ground, shaped and bent with heat etc. I made new shear blades from ford light truck springs for a heavy duty manual rebar cutter that have held up for years. Chainsaw bars are mostly three laminated layers now. Lawn mower blades have worked very well for several projects or repairs for me.
My forge is a propane bottle, a propane weed burner torch and fire brick or my oxy rig,
chuck

 

[KevinD]

Mark, I offer this advise as someone who has never made a knife (I just hate that much bench work) but have done a lot of forging for horseshoeing and ornamental iron. I'd recommend you start with practice pieces of mild steel to develop your forging skill. Make some letter openers, etc. Although oil and water quench steels are quite forge-able they have narrower ranges of forging and are more unforgiving of overheating, cold shuts and cracks and make that sickening "PING" sound when you want to get in one last whack after spending a couple hours/days/weeks hammering on your masterpiece. Your scrap pile will be much cheaper and the learning curve is easier to swallow.

Is your forge gas or coal?

 

[markknx]

Kevin my forge is gas, but I am building a brake drum forge also.
Yes I am using old pieces of mild steel 3/8 square and round for practice. I have quite a bit of this savaged from shipping braces on hand rails and the like.
Mark