knife steel?

[edge9001]

I found my local hardware store sells these nails. I would guess they are for concrete or block. the nails are approximatly 8 inches long, and suprisingly hold a descent edge. any idea what these nails are used for or what kind of steel they are made of? I'll try and post pictures as soon as I can.

[Karl]

Do you have a photo?
they could be a decking spike...

[edge9001]

I only have one left it's a bit rusty

The nail head was cut off, but only less than a 1/2 inch from the cut end.

that is a AA battery for size reference

I made a small blade to use in my shop, although it is ugly and the handle is just a wrapping of electrical tape, it amazingly enough holds an edge well.

[Don A]

Do some research on spark testing. That will tell you a lot.

Also, forge one down kinda thin, heat it to non-mag, and water quench it.

Put it in your vise and bend it. If it's hardenable steel, it should snap like a twig. If it bends, it's probably mild.

[Rich Hale]

Using steel for a blade can be easier if you consider what the steel used was chosen for in the shape that you found it. And we must also consider economics. For instance the nail you described is designed to hold things together as it is driven into the pieces. Which also means it must have a pointed end that likely has some flats on it that act as edges to cut through the wood as it is driven. I would consider that a splitting rather than a cutting event. It really does not need the composition of steel that would make it really resistant to bending as it is driven or the ability to take and maintain a fine edge when used as a slicing or cutting tool. Now to the economics: To get more of the things I just mentioned above would require a different steel that what I expect is used for that nail. That would raise the price quite a bit depending on what the steel they used actually is.
Steel I prefer have from .72 carbon content up to around 1.0. Lots of folks get by with less C content but most of us might agree that below .5 C is not a good choice for knives.
In the past I made a few rifle stocks. I found out early that although pine was al ot easieer for the rough shaping in the end if I finished it, no matter how nice a job I had done I had a pine stock. If i used fine walnut I had somet4hing worthy of the efforts I had spent.
There are many steels you can use that are easily found that have the above features. Higher c percentage, and the ability to keep shape and a working cutting edge you can achieve in most home forge shops with information you can find on this site. Maybe the easiest to find is spring stock from vehicles. Coil or leaf. Search here for the abs testing information on seeing wot your finished blade should really do. And have fun. ( and I do not know wot that steel in the nail really is)

[edge9001]

Do some research on spark testing. That will tell you a lot.

Also, forge one down kinda thin, heat it to non-mag, and water quench it.

Put it in your vise and bend it. If it's hardenable steel, it should snap like a twig. If it bends, it's probably mild.

I have the one ugly blade i alreay made, it can be my sacrificial (spelling?) piece. I'll let you know what i find out.