The comment wasn't meant as argumentative, but as educational.
As a arbitrary debate ( I have no personal stake in whether someone knows what his steel actually is ) - lets go with your scenario.
Knifemaker Bob has been given a large amount of some steel that he has been told is some kind of spring steel.
After annealing the steel, he can do a series of tests ( about ten to twenty test blades to get a good reliable set of HT parameters), and get reasonably good blades from this steel.This would take a hobby smith a couple of months, and cost $50-60 in gas, electricity, and belts. He would then know how to HT the steel for a knife with good performance (maybe the best performance....maybe not), but still would not know what the steel was. It could be 9260, or 5160, or 1060....and would have about the same HT. At the end he may have a few usable test blades left, depending on how many were tested to destruction, and how many had a good HT.
OR - He could purchase a 22 foot long bar of 1.5X.25" 5160 from Admiral or a spring shop for less than $100, including shipping.The HT specs are provided by the seller, and/or are readily available from any metallurgical reference book.
That would make more than 20 knives for most makers. For a cost of about $150 (including the gas, electricity, and belts), or about $7.50 a knife to make the blades.
So, unless he is in the business of selling knives, he could make a knife every two weeks for a year from the one bar of known steel.
If he is a hobbiest, then using the found steel may bring joy to his heart. Saving money is important to most folks.
However, if he sells knives, he must be able to tell the purchaser what the steel is. He can say, "Some kind of spring steel." and that will work for some buyers. As the price goes up, and the buyer becomes more sophisticated, that answer often won't be good enough.
OK, so Knifemaker Bob starts out using this steel, sells some knives,and his customers are fine with it for the camp knives he made them. Later he becomes a more talented smith and makes better quality knives, and more of them. Will some of his former clients still remember that his knives are made from, "Some Kind of Steel"??? Even if he is now using a known steel, they may still think that.
This is a summation of where I was getting at with the post I made.
Yes, with the proper skills and testing,you can make a good knife from found steel.
Yes, many smiths (mostly ones who had attained a reasonable level of skill and equipment) make great blades from ball bearings and planer blades. They did, however, already know that the bearings were indeed 52100, or the planer blades were indeed D-2 before they made the knife. ( A planer blade may be anything from 10XX steel to D-2, to carbide- very different HT's).
No, found steel is not a good way to start learning forging and knifemaking.
Using a known steel is the way to start.
No, you won't know what it is unless you have it analyzed.
Having a sample analyzed ( it only takes a 2"X2" piece) is a cheap way to turn that pile of donated steel into a knifemakers bonanza. Costs run form about $20 to $50-60 for most labs. A forumite here would test a piece for free a while back (I'll leave it to him to volunteer).
Stacy
