This article is part of the CNC Machining Materials Guide: Metals, Plastics & Superalloys on CNX Precision.
If you are specifying brass for CNC parts, the brass 360 vs 260 decision affects machining cost, corrosion performance, and final part strength. This guide explains the composition, machinability, corrosion resistance, strength, and cost of these two workhorse alloys, and it tells you exactly when to select each one for your precision components. Buyers who understand the trade-offs avoid expensive re-specs and missed delivery dates.
Alloy Composition: 360 vs 260 at a Glance
Brass 360 is the official designation for C36000 free-cutting brass. It contains roughly 61.5 percent copper, about 3 percent lead, and the balance zinc. Lead is the critical ingredient. It acts as an internal lubricant and chip breaker, which is why 360 produces short, broken chips and cuts cleanly at high spindle speeds. The names Alloy 360 and free-cutting brass are used interchangeably across machine shops.
Brass 260 is the official designation for C26000 cartridge brass. It is a 70/30 alloy with roughly 70 percent copper and 30 percent zinc, and it contains no added lead. Note that 260 contains no tin, despite a common misconception. The alloy family that adds tin for seawater service is naval brass, such as C46400. Keep the copper, the zinc, and the absence of lead in mind for the rest of this brass 360 vs 260 comparison.
That composition gap drives nearly every difference in machinability, corrosion resistance, strength, and cost that follows. Machining data, bar stock pricing, and application references all trace back to the alloy families, so check the designations on material certificates before production starts.
Machinability: Why 360 Leads CNC Turned Parts
Machinability ratings are expressed relative to brass 360, which holds the industry baseline of 100 percent. Brass 260 rates near 30 percent. That single number explains why 360 dominates high-volume CNC turning, including fitting bodies, valve stems, terminals, and threaded fasteners.
In practice, the gap appears in cycle time, tool life, and surface finish. Brass 360 cuts fast, holds tight tolerances, and leaves clean threads and fine finishes on both outside and inside features. Chips break predictably into short segments, which supports unattended machining and reduces cleanout time. For deep holes, cross-drilled ports, and fine pitch threads, 360 is the dependable choice.
Brass 260 is fully workable on a CNC lathe, but it demands sharper tooling, careful feed selection, and more attention to chip control. Dull tools can tear or smear the surface, and stringy chips can wrap around tooling if parameters drift. Design for 260 benefits from slightly larger corner radii and robust toolpath planning. For most shops, every brass 360 vs 260 quote starts with this machinability gap.
Secondary work also separates the alloys. Brass 360 polishes to a bright finish quickly, and it accepts plating, passivation, and clear coatings without issues. Brass 260 receives similar finishes, but its softer, more ductile surface calls for slightly different polishing practice.
Corrosion Resistance and Strength Compared
Brass 260 offers the better corrosion resistance of the pair. Its higher copper content resists dezincification in fresh water and common atmospheric conditions, which is why cartridge brass appears in plumbing, radiator, and hardware applications. Brass 360 is adequate for many indoor and outdoor uses, but its higher zinc content makes it more vulnerable to dezincification in aggressive water or condensate. For parts that spend their life damp, the brass 360 vs 260 corrosion gap is decisive.
Neither alloy is the first choice for prolonged seawater immersion. That role belongs to tin-bearing grades such as naval brass. For continuous saltwater service, specify a naval grade rather than either copper-zinc alloy.
On strength, 260 responds well to cold working. Hard and extra-hard tempers reach higher tensile strength than annealed stock, which suits spring contacts, clips, and structural hardware. Brass 360 offers moderate strength that is fully adequate for fittings, valves, and connectors, although it is rarely the strongest option in demanding structural service. Ductility also separates the alloys: 260 bends, forms, and crimps with less risk of cracking, so it stands up to secondary forming steps.
Cost and Supply Considerations
Raw material cost usually favors brass 360. Its copper content sits near 62 percent, while 260 sits near 70 percent, and copper typically drives the price of brass. Contract manufacturers also stock 360 bar stock in many diameters because it is the default free-cutting grade, which shortens lead time for common part sizes.
Machining cost also favors 360. Faster cycles, longer tool life, and fewer burr conditions translate into lower cost per part. For high-volume projects, the brass 360 vs 260 cost gap on the shop floor can exceed the material price gap. When a part runs on multiple spindles for weeks at a time, that difference can decide which supplier wins the contract.
Regulation adds another factor. Leaded brass 360 faces restrictions in potable water and some consumer products under lead content rules. Brass 260 is lead-free, so it clears those programs without extra paperwork. Lead-free alternatives to 360 also exist for parts that must not use lead, so a compliant option is available for nearly every geometry.
Lead time is a practical concern as well. Because 360 is common, suppliers keep inventory and quote shorter lead times. Brass 260 bar stock is available but often from fewer sources, so procurement planning matters more for larger runs.
Brass 360 vs 260: Which Alloy Fits Your Parts
Choose brass 360 for high-volume turned parts where machinability drives cost. Fittings, valve bodies, gas and water connectors, terminals, and threaded fasteners are classic candidates. The alloy also rewards parts with deep holes, fine threads, and complex profiles because of its chip behavior and surface finish.
Choose brass 260 for parts that require ductility, cold forming, or higher strength in hard tempers. Think radiator components, stamped or drawn hardware, lead-free plumbing parts, and spring contacts that must hold their shape. The alloy machines fine in small batches, so it works for prototypes and custom runs as well.
Review the brass 360 vs 260 trade-off against your part geometry, service environment, and annual volume. For machined components, 360 delivers the fastest path to low unit cost. For formed parts or water-exposed parts, 260 is the safer, compliant choice. When seawater is the real requirement, move to a naval grade and keep both of these alloys out of the specification. If you are unsure which direction fits, run prototypes in both materials and compare cycle time, tool wear, and final properties under your real assembly conditions.
Frequently Asked Questions
Is brass 360 easier to machine than brass 260?
Yes. Brass 360 holds the machinability baseline of 100 percent, while brass 260 rates near 30 percent. That difference appears as faster cycles, longer tool life, and cleaner finishes on CNC lathes and mills.
Does brass 260 contain tin?
No. Brass 260 is a 70/30 copper-zinc alloy without tin. Tin-bearing alloys such as naval brass C46400 provide the seawater resistance that people sometimes associate with cartridge brass.
Which brass is better for seawater exposure?
Neither 360 nor 260 is ideal for continuous seawater service. Specify a tin-bearing naval grade when parts face long-term saltwater immersion, and keep 360 or 260 for fresh water and indoor applications.
For related information, see our guide to brass vs copper cnc machining and brass cnc machining, and brass vs bronze.