--- title: Tool Steels: A2, D2, O1, S7 and H13 | Wolf Machine Reno url: https://wolfmachinenv.com/materials/tool-steels/ business: Wolf Machine & Fabrication, Inc. address: 4812 Longley Ln, Reno, NV 89502 phone: (775) 359-5570 hours: Shop Monday-Friday 7:00 am-3:30 pm; closed Saturday and Sunday type: Metal and plastic fabrication and machining (custom and CNC machining, welding, metal and plastic fabrication, gearbox and part repair, align boring, metal spray) --- [Photo: Stock photo: a milling cutter taking a finishing pass on a steel block, coolant line beside it] - [Home](https://wolfmachinenv.com/) - [Materials we machine](https://wolfmachinenv.com/materials/) - Tool steels # Tool steels for dies, punches and wear parts We machine tool steels at our Reno shop, and they tie directly to our tool and die work. They are the hard, wear-resistant steels used for dies, punches, cutters and fixtures, and they are usually machined in their soft state and finished after hardening. Stock photo: a milling cutter taking a finishing pass on a steel block, coolant line beside it A tool steel is made to cut, shape or form other materials, and to keep its edge doing it. The letter in the name tells you how it is hardened and what it is for. Here is a short guide before you pick one for a drawing. ## At a glance - We machine tool steels at our Reno shop - A2, D2, O1, S7 and H13 families - Dies, punches, wear plates and fixtures - Rough machined soft, finished after hardening - Ties to our tool and die work I have used Wolf Machine several times over the past few years for fabricating and repair of parts on my ultralight aircraft. [...] These guys are great to deal with. I wouldn't take my projects anywhere else. James B. ยท Google review, September 2023 [Leave us a Google review](https://search.google.com/local/writereview?placeid=ChIJVWVOfCI_mYARibcFMPsDEKc) ## The common families, as general education The table is general knowledge from published sources, not the shop's stock. Name the grade on your drawing, or tell us what the tool has to do and what it works on. | Grade | Family | Known for | Typical use | |---|---|---|---| | O1 | Oil hardening | Easy to machine and harden, holds an edge | Punches, gauges, fixture parts | | A2 | Air hardening | Stable in heat treatment, good wear | Dies, punches, forming tools | | D2 | High carbon, high chromium | Very high wear resistance | Blanking dies, long-run wear parts | | S7 | Shock resisting | Takes impact without chipping | Chisels, punches, shear blades | | H13 | Hot work | Holds strength at high heat | Die casting and extrusion tooling | ## Machined soft, finished hard A tool steel is normally cut while it is soft, close to the final size, with a small amount of material left for finishing. It is then hardened, and the surfaces that matter are finished afterward, usually by grinding. A part that must be flat or round to a tight callout is planned around that sequence. Hardness is written on a print as a Rockwell C number. The glossary entry on [Rockwell hardness](https://wolfmachinenv.com/glossary/rockwell-hardness/) explains the scale. Harder parts are cut with tools made for the job, at slower speeds. ## Tool steel and tool and die work Tool and die work is one of our specialties, and tool steels are its main material. See the page on [tool and die work](https://wolfmachinenv.com/services/tool-and-die-work/) for the process side. Send the drawing, the grade, the hardness callout, the quantity and what the tool does. Use the quote request or call [(775) 359-5570](tel:(775)%20359-5570). For general steels see [steels and steel alloys](https://wolfmachinenv.com/materials/steel-and-steel-alloys/). ### Sources - [Tool steel (overview)](https://en.wikipedia.org/wiki/Tool_steel) (2026-10-18) ### Tool steel parts - Punches and die sections - Wear plates and guide rails - Cutters and knives - Gauge and fixture parts - Hot work tooling parts ### How to send us the job Have a print? Attach it to the quote request. No print? Photos of every face, the sizes you know and the machine the part came from are a good start, and you can bring the part in. [Request a quote](#quote) [What to put on a drawing](https://wolfmachinenv.com/guides/what-to-put-on-a-drawing/) ### Talk to the shop [(775) 359-5570](tel:(775)%20359-5570) | Monday to Friday | 7:00 am - 3:30 pm | |---|---| | Saturday and Sunday | Closed | [Request a quote](#quote) ### Related - [Tool and die work](https://wolfmachinenv.com/services/tool-and-die-work/) - [Steels and steel alloys](https://wolfmachinenv.com/materials/steel-and-steel-alloys/) - [Rockwell hardness](https://wolfmachinenv.com/glossary/rockwell-hardness/) - [Blanchard grinding](https://wolfmachinenv.com/services/blanchard-grinding/) - [Materials we machine](https://wolfmachinenv.com/materials/) ### Terms on this page [Rockwell hardness](https://wolfmachinenv.com/glossary/rockwell-hardness/) [The full glossary](https://wolfmachinenv.com/glossary/) ## Other materials [Aluminum](https://wolfmachinenv.com/materials/aluminum/) [Brass](https://wolfmachinenv.com/materials/brass/) [Bronze](https://wolfmachinenv.com/materials/bronze/) [Copper](https://wolfmachinenv.com/materials/copper/) [Plastics](https://wolfmachinenv.com/materials/plastics/) [Stainless steel](https://wolfmachinenv.com/materials/stainless-steel/) [Steels and steel alloys](https://wolfmachinenv.com/materials/steel-and-steel-alloys/) [Titanium](https://wolfmachinenv.com/materials/titanium/) ## Questions people ask Still have a question? Call [(775) 359-5570](tel:(775)%20359-5570), Monday to Friday, 7:00 am to 3:30 pm. ### What does the letter in a tool steel name mean? It shows how the steel is hardened or what it is for: O is oil hardening, A is air hardening, D is high carbon and chromium, S is shock resisting, and H is hot work. ### Do I need to know the tool steel grade? A grade on the drawing is best. If you only have the old tool, tell us what it did and what it worked on. [Photo: Stock photo: a lathe turning a bar, hot chips flying] ## Request a quote Tell us what you need, attach a drawing or photos of the part, and we will get back to you during shop hours. Free consultations; prompt estimates. [Call (775) 359-5570](tel:(775)%20359-5570) - From your specifications, drawings or samples. We can also assist you in designing your product or part. - Free consultations and prompt estimates - Stands behind the work: Our rates are very competitive and our quality is second-to-none. Wolf Machine stands behind the work we perform. - Company accounts: all major credit cards, or we can open an account for your company Shop hours Monday to Friday, 7:00 am to 3:30 pm. Send your request any time and we will get back to you during shop hours. Stock photo: a lathe turning a bar, hot chips flying