Origin ?

[Lew]

Originally Posted by asomotif

I am not a metalurgist, but with my practical knowledge I have a few questions / remarks.

- A file is hard and brittle. not the best material to make a knife
- a file is often not as broad as this knife is.
- a file's surface is often flat while this blade is getting thinner towards the edges is away that I have never seen in a file.
So if you would reshape a file, the original grooves of the filw ould remain vissible in th emiddle but surely not towards the edges.

So my idea is that this knife is not made from a file, but maybe the grooves/stripes are caused by shaping the steel, with a very rough file.
So in fact they are filling marks

Asomotif

Knives have been forged from files for hundreds of years. Many American revolutionary black smiths used them as their source of steel which was hard to come by in those days.Yes files are quite hard but the smith anneals them in the forge to soften them up. When you forge the hammer blows spread the tapers out in the file which widens the profile of the blade being made. I collected custom made forged knives for years before getting into antique knives and I have owned many knives forged from files,rasps and even steel cable.

Lew

[Ferguson]

What Lew said is correct. Probably made from a rasp, which has large coarse teeth made for cutting soft material like wood.

Files and rasps come in all sizes, some fairly large. As the blade is forged down to a thin edge, it gets wider, and retains the pattern of the teeth.

Files are hard and brittle because of the heat treatment. They are made that way to cut steel. Brittleness is not an issue because there is no impact involved. Further tempering (heating at a low temp, maybe 350 fareinheit) reduces hardness and increases toughness, which is what you want for a knife blade.

This gile was forged from a file, or rasp.

Edit:
A file that is .25" thick by 1.5" wide has a cross sectional area of .375 square inches.
A diamond shaped blade .1875" thick at the center, 3" wide has a cross sectional area of only .2813 square inches.
So it's easy to see that a rectangular file could be forged into a fairly wide diamond sectioned blade.


Steve

[asomotif]

Thanks Lew ann Steve for the explanation !

I am happy that I already excused myself as not being a metalurgist.

the hammer blows spread the tapers out in the file

This is indeed one of the things that I overlooked when drawing my conclusions.
Not to speak about the temperature issues and the square inch calculation

Best regards,
Willem