Knifemakers, shop tooling builders, and anyone making punches or dies eventually hits the same question: O1 or A2? Both are popular tool steels, and both can make excellent tools, but they behave very differently once you start heat treating.
O1 is an oil-hardening tool steel. It hardens at relatively low temperatures and is forgiving for a home shop with a forge or a basic heat treat oven, which is why so many first-time knifemakers start with it. It takes a fine edge and machines well before hardening, though it can move or warp more during the quench.
A2 is an air-hardening tool steel. It needs higher temperatures and more controlled heat treating, but it holds its shape better through hardening and offers a strong balance of wear resistance and toughness. That's why it shows up in punches, dies, shear blades, and shop fixtures that need to stay dimensionally accurate.
Our Marietta team can help you match a tool steel to the job and cut it to the length you need, with no minimum. Stock changes, so check with the counter on what's on the rack today. What was the first tool or blade you ever made from tool steel?
#ToolSteel #Knifemaking
Authentic close-up of tool steel bar stock on the racks at the Marietta location, or a customer's finished knife blank, punch, or die made from O1 or A2. Clean bar ends with grade markings visible work well. Real photos strongly preferred over stock. No Google Drive image folder is set up for this client yet, so request a real photo from the Marietta location.
Canva text suggestion: "O1 or A2? It Depends on Your Heat Treat" or "Oil-Hardening vs. Air-Hardening Tool Steel"