Brass Machining and Supply in San Bernardino, CA — C360, C260, and Naval Brass

C360 (UNS C36000) is the machinability standard against which all other metals are rated — 100% on the standard machinability index, which means every other metal is rated relative to C360's chip-breaking behavior, cutting speed capability, and surface finish quality. Its composition (61.5% Cu, 35.5% Zn, 3% Pb) includes lead as a chip-breaking agent, which gives it chip sizes and cutting behavior that are as close to ideal as any metal gets. San Bernardino CNC shops run C360 round bar on Swiss-type and multi-spindle lathes at surface footage of 200–300 SFM with HSS tooling and 400+ SFM with carbide — cycle times that are 3–5x faster than stainless steel and 2–3x faster than aluminum for equivalent complexity parts. In San Bernardino's industrial supply chain, C360 is the specification for valve bodies, pneumatic fittings, fluid couplings, instrument components, electrical terminals, and screw machine products produced in volume. The automotive aftermarket manufacturing concentrated in the Inland Empire uses C360 for sensor housings, fuel system fittings, and carburetor components where the combination of corrosion resistance, machinability, and thread-cutting performance justifies its cost premium over aluminum. The lead content in C360 provides both the machinability advantage and a mild galling resistance that helps threaded fittings resist seizing during installation and service. Important limitation: C360's lead content makes it non-compliant with California's Prop 65 and with NSF/ANSI 61 requirements for potable water contact. Plumbing fittings and water system components installed in California must use low-lead or lead-free brass alloys — C87850 (CDA Silicon Brass), C69300 (Eco Brass), or NSF-certified C36000 substitutes. San Bernardino buyers sourcing brass for plumbing or water-contact applications must confirm the alloy's NSF 61 certification and lead content declaration before specifying C360.

C260 (UNS C26000, cartridge brass) has 70% copper and 30% zinc — the classic 70/30 composition that has defined deep-draw and cold-forming brass for over a century. Named for its use in ammunition cartridge cases (which require extreme cold-working without cracking), C260 has elongation values of 60–68% in the annealed condition, making it the correct specification for any brass application involving significant forming, bending, drawing, or stamping. Where C360 machines well but forms poorly (the lead that aids chip breaking also causes cracking during cold working), C260 forms superbly and machines acceptably — machinability rating of about 30% relative to C360. In San Bernardino's manufacturing base, C260 is specified for stamped electrical contacts, formed sheet metal brackets and enclosures, deep-drawn cups and shells, and cold-headed fasteners. The construction hardware sector uses C260 sheet for decorative trim, kick plates, and architectural elements where the combination of appearance, corrosion resistance, and forming behavior is the governing requirement. Gauges from 0.005 in. through 0.125 in. are stocked by local and LA-basin distributors; heavier plate (above 1/4 in.) typically requires special order. For spring applications, C260 in the spring temper (H08) delivers 0.2% yield strength of 63,000 psi with the fatigue endurance that makes it suitable for contact springs, retaining clips, and formed hardware that sees repeated deflection. San Bernardino shops forming C260 spring temper use larger bend radii than for the annealed condition (minimum 2–3x material thickness in the transverse direction) to avoid cracking at the bend — confirm temper and bending direction relative to the rolling direction before tooling a part.

Naval brass (C46400, UNS C46400) is essentially a 60/40 yellow brass with 0.5–1.0% tin added specifically to inhibit dezincification — the selective corrosion of zinc from the brass matrix that occurs in stagnant water, chlorinated water, and seawater service. In standard 60/40 brass (C28000 Muntz Metal), prolonged contact with these waters can leach zinc selectively from the alloy, leaving a porous, weakened copper matrix with no structural integrity. Naval brass's tin addition dramatically slows this attack, which is why it was the traditional material for marine hardware, boat shaft components, and saltwater plumbing systems. In the San Bernardino and Inland Empire context, naval brass shows up in water treatment infrastructure hardware, irrigation system components, and industrial fluid-handling systems where the service water chemistry includes chlorine or high mineral content. The Inland Empire's water infrastructure, fed by groundwater sources with variable mineral content, creates specific conditions where dezincification-resistant alloys are specified by forward-looking engineers. Naval brass machines reasonably well — machinability around 30% relative to C360 — and welds satisfactorily with brass or silicon bronze filler. Strength values for naval brass: tensile 54,000–74,000 psi depending on temper (annealed to half-hard), with good ductility in the annealed condition for forming and good strength in the worked tempers for threaded and structural applications. It is available in bar, rod, tube, and plate from specialty brass distributors in Southern California, typically with 1–2 week lead time for standard sizes.

Brass pricing at local distributors and service centers tracks the COMEX copper price (brass is roughly 60–70% copper by weight) plus a zinc premium and processing margin. Unlike steel, which has published commodity price indexes, brass pricing is updated frequently and varies between distributors — getting multiple quotes on brass material orders of any significant size is worthwhile. C360 round bar is the most consistently stocked brass grade in the Inland Empire, with same-day availability in 1/2 in. through 3 in. diameters from electrical supply houses and metal service centers. C260 sheet and strip are available from metals distributors in standard gauges with 3–7 business day delivery. Naval brass bar is a specialty item with 1–2 week lead time from LA-basin distributors. For CNC machined brass parts, San Bernardino shops can typically deliver in 1–2 weeks for turned parts from C360 bar stock in quantities of 10–100 pieces. Higher volumes and complex milled parts extend to 3–4 weeks. Swiss-type lathe capability for small-diameter precision parts (under 1 in. diameter) is available in the Inland Empire at shops serving the automotive and electronics industries. For construction and plumbing hardware sourcing in San Bernardino, the local plumbing supply trade (Ferguson, various Inland Empire distributors) stocks NSF-certified brass fittings and valve bodies in standard configurations for immediate availability. Custom fittings and non-standard configurations are CNC machined from C360 bar (with appropriate lead-content declarations for non-potable applications) or from NSF-compliant alloys for potable water service.

California's regulatory environment imposes specific requirements on brass used in potable water applications that go beyond general industry standards. AB 1953 (effective 2010) and the federal Reduction of Lead in Drinking Water Act require that brass alloys used in pipes, fittings, fixtures, and components in contact with potable water contain no more than a weighted average of 0.25% lead — effectively eliminating C360 and other traditional free-machining brasses from these applications. NSF/ANSI 61 certification is required for plumbing components in contact with drinking water, covering not just the lead content of the alloy but also the potential for leaching of other metals and compounds from the material and surface treatments. Lead-free brass alternatives specified for California potable water work include C87850 and C69300 (marketed as 'Eco Brass' and similar trade names), which replace lead with bismuth or silicon as a machinability aid. These alloys machine significantly worse than C360 — machinability ratings of 30–40% compared to C360's 100% — adding cost and cycle time to machined parts. Suppliers in San Bernardino serving the commercial construction and plumbing market maintain inventory of NSF-certified lead-free fittings and stock lead-free brass bar for custom machined fittings. For industrial (non-potable) applications — pneumatic systems, hydraulic fittings, electrical components — C360 and its lead content are fully permissible. Confirm the application's water-contact status before specifying the alloy; mixing up potable and non-potable specifications is a common source of costly rework and project delay in commercial construction projects.