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Picking the wrong carbon steel grade costs you in cycle time, tool wear, and scrap. Forte Precision Metals has supplied carbon steel round bar from Franklin Park, IL, since 1994, and grade selection is the first conversation we have with almost every new shop.
Carbon steel is strong, affordable, and machinable. But each grade behaves differently under a turning tool. Knowing which one fits your operation before you order saves time and money on the floor.
Carbon Steel Grade Selection for CNC Turning Operations
The grade you specify shapes everything downstream, from chip control to part performance. We stock a full range of carbon steel round bar grades, so you can match material to operation without sourcing from multiple suppliers.
Getting this right at the purchase order stage means fewer surprises at the machine. Below, we’ve broken the grades into groups based on what matters most to a CNC turning operation.
Free Machining Grades for High Volume Output
For shops where cycle time is the primary metric, the free machining grades are where to start. 12L14 and 1215 are the fastest cutting grades we carry, and both produce clean chips that keep high-volume turning operations running without constant interruptions.
11L17 and 11L41 belong in the same conversation. All four grades are built for screw machine work and tight tolerance, small diameter parts running at high quantities. Before specifying any of these, confirm your weldability requirements with your engineering team, as these grades prioritize machining performance above other attributes.
General Purpose Grades for Strength and Consistency
1018 is the most common low-carbon grade we stock. It machines cleanly, welds without difficulty, and suits shafts, pins, and general structural components reliably across high-volume runs.
1020 and 1026 sit just above 1018 in carbon content and turn cleanly in most setups. 1144 steps up in strength while remaining machinable, and we stock it in two forms: 1144 and 1144 Carbon Round Bar Stock. 1141 is also available for applications where strength and machinability both factor into the grade decision.
Higher Carbon Grades for Wear Resistance
1045 responds well to heat treatment and suits gears, shafts, and pins that face wear in service. Machinability is lower than the grades above, so expect adjusted feeds and speeds at the machine.
We also stock High Carbon Steel Round Bar for applications where abrasion resistance is the primary driver. If your turned parts need to perform harder in the field, this end of the carbon steel range is where to look.
Specialty Carbon Grades for Specific Applications
8620 is the most widely used carburizing alloy in our carbon steel inventory, suited for camshafts, gears, and fasteners that go into a carburizing furnace after turning. 86L20 is also available for applications that follow a similar path.
FatigueProof carbon round bar and ST52-3 DOM round out the specialty end of our carbon steel range. If your application falls outside the standard grades covered above, reach out, and we’ll point you to the right option.
How Precision Ground Bar Supports Your Turning Program
Once you’ve confirmed your grade, the form of bar stock you order shapes how your turning program actually runs. Our centerless grinding operation produces carbon steel round bars to tolerances as tight as plus or minus .0001 inch, with a microfinish down to 8RA. Consistent bar dimensions mean your program runs the same way on bar one and bar one thousand.
Cut-to-length service through our CNC saws handles singles and bundles. Bar chamfering removes sharp ends before the bar reaches your spindle. Rotary bar straightening handles any camber in incoming stock before it affects your first operation.
Get the Right Carbon Steel Bar for Your Next CNC Run
Call our team at (847) 451-8888, Monday through Saturday, 7 AM to 5 PM. Tell us your grade, diameter, length, quantity, and whether you need precision-ground or cold-finished bar.
You can also submit your full specs online through our “Request a Quote” form. We’ll follow up with availability and get your order moving.
Frequently Asked Questions
Which carbon steel grade machines fastest in CNC turning?
12L14 and 1215 are the fastest options we stock. Both are built for high-volume turning and produce clean chips that keep your operation running without interruption.
What is the difference between a precision-ground bar and a cold-finish bar?
Precision ground bar holds tolerances as tight as plus or minus .0001 inch with a microfinish down to 8RA. Cold finish bar offers tighter control than hot-rolled stock but does not reach the same dimensional accuracy.
Can Forte Precision Metals supply a carbon steel bar cut to length?
Yes. Our CNC saw cutting service covers cut-to-length jobs for both singles and bundles. Just include your length requirement when you submit your quote request.
Which grade suits carburizing applications after CNC turning?
8620 is the standard choice for camshafts, gears, and fasteners going into a carburizing furnace. Forte Precision Metals also stocks 86L20 for similar applications.
