---
title: "Bronze Machining | Bearing, Phosphor & Aluminum Bronze | OpenSpindle"
description: "Get quotes for custom bronze parts from independent machine shops. Bearing, phosphor, and aluminum bronze machined into bushings, bearings, and fittings. Upload a drawing."
canonical: https://openspindle.com/materials/bronze
---

# Custom bronze parts from independent machine shops

Bronze is the go-to for bearings and bushings: it runs against steel with low friction, carries load, and resists wear and corrosion. Upload a drawing and hear back from shops that turn and mill bronze bar, plate, and sleeve stock.

## Bronze shops on OpenSpindle

Real shops that turn and mill bronze bearings, bushings, and fittings. See their equipment and get a competitive quote.

[Browse all bronze shops](https://openspindle.com/manufacturers?material=Bronze)

## Bronze grades shops run most

Bronze is a family of copper alloys tuned for bearing, strength, or corrosion duty. These are the ones you will see quoted.

### C932 / SAE 660 bearing bronze

The classic leaded tin bronze for bushings and bearings. Machines beautifully, runs against steel with low friction, and tolerates marginal lubrication.

**Best for:** Bushings, bearings, thrust washers, sleeves

### C544 phosphor bronze

A tin-phosphor bronze with high strength, fatigue resistance, and good spring properties. Wear-resistant for gears and heavily loaded bearings.

**Best for:** Gears, heavy-load bearings, springs, contacts

### C954 aluminum bronze

An aluminum bronze with steel-like strength and excellent corrosion and wear resistance, including in seawater. The choice for tough, marine, and high-load parts.

**Best for:** Valve parts, marine hardware, high-load bushings

### C630 nickel-aluminum bronze

Adds nickel for even higher strength and outstanding seawater corrosion resistance, used for marine propellers and pump components.

**Best for:** Marine propellers, pump and valve components

### C864 manganese bronze

A high-strength brass-family bronze for heavily loaded structural bearings and gears where strength matters more than the lowest friction.

**Best for:** Structural bearings, gears, heavy machinery

## Material Properties

Representative values for C932 bearing bronze. Exact numbers vary widely across the bronze family.

| Property | Value |
| --- | --- |
| Density | ~8.8 g/cm³ (0.318 lb/in³) |
| Tensile strength (C932) | ~35 ksi (240 MPa) |
| Tensile strength (aluminum bronze) | ~85 ksi (585 MPa) |
| Hardness (C932) | ~65 HB |
| Machinability (C932) | Excellent; free-cutting leaded bronze |
| Corrosion resistance | Good; aluminum and nickel bronzes excel in seawater |
| Friction / bearing | Low friction against steel; tolerates marginal lube |
| Conductivity | Moderate electrical and thermal conductivity |

Match the bronze to the duty: leaded tin bronze for easy-running bearings, phosphor or aluminum bronze for strength and heavy loads.

## Stock Forms

- **Round bar** -- Turned bushings, bearings, shafts, and fittings.
- **Plate & block** -- Milled bearing pads, wear plates, and gibs.
- **Tube & sleeve** -- Continuous-cast sleeve stock for bushings.

## Processes That Run This Material

- [CNC Turning](https://openspindle.com/capabilities/cnc-turning.md) -- Turned bushings, bearings, and fittings from bar and sleeve.
- [CNC Machining](https://openspindle.com/capabilities/cnc-machining.md) -- Milled bearing pads, wear plates, and housings.
- [CNC Machining · 5-Axis](https://openspindle.com/capabilities/5-axis-machining.md) -- Complex valve and pump geometry in a single setup.
- [Precision Grinding](https://openspindle.com/capabilities/precision-grinding.md) -- Ground bearing bores and journals to a fine finish.

## Finishes

Bronze resists corrosion on its own, so most parts ship as-machined. Bearings are finished for fit and surface quality.

- **As-machined** -- Bare bronze needs no coating and ships as-machined for most parts.
- **Honed / ground bore** -- Bushing and bearing bores are honed or ground to a precise diameter and fine surface for the running fit.
- **Oil-impregnated (sintered)** -- For sintered bronze bearings, the porous structure is oil-impregnated for self-lubrication; a different process from machined bar.
- **Bead blast** -- A uniform matte texture that evens out machining marks on cosmetic parts.

For bearings, call out the bore diameter, running fit, and surface finish. Note the mating shaft material so the shop confirms the pairing.

## Applications

- Industrial / OEM
- Robotics & automation
- Marine
- Energy / oil & gas
- Heavy machinery
- Pumps & valves

Bronze shows up wherever parts slide, carry load, or sit in a corrosive environment.

## How It Compares

How bronze compares to the other metals shops quote for bearing and fitting work.

### [Brass](https://openspindle.com/materials/brass.md)

- Bronze (a copper-tin alloy) is stronger, harder, and a better bearing material than brass
- Brass (copper-zinc) is cheaper, machines even faster, and is the choice for fittings and decorative parts
- Bronze resists seawater and wear far better; brass is easier and cheaper for non-bearing work

**Verdict:** Choose bronze for bearings, bushings, and marine wear parts. Choose brass for low-cost fittings, connectors, and decorative parts.

### [Stainless Steel](https://openspindle.com/materials/stainless-steel.md)

- Bronze runs against a steel shaft with low friction where stainless would gall
- Stainless is far stronger and harder for structural parts
- Bronze is the bearing surface; stainless is the structure it often runs against

**Verdict:** Choose bronze for the bearing or bushing. Choose stainless for the strong, corrosion-resistant structure or shaft.

## Frequently Asked Questions

### What is the best bronze for bearings and bushings?

C932 (SAE 660) leaded tin bronze is the classic bearing bronze: it machines beautifully, runs against a steel shaft with low friction, and tolerates marginal lubrication. For heavier loads or higher strength, phosphor bronze (C544) and aluminum bronze (C954) are used. Note the load, speed, and lubrication so the shop confirms the grade.

### What is the difference between bronze and brass?

Bronze is primarily a copper-tin alloy; brass is copper-zinc. Bronze is stronger, harder, more wear- and corrosion-resistant, and the standard bearing material. Brass is cheaper, machines even faster, and is favored for fittings, connectors, and decorative parts. Use bronze for bearings and marine parts, brass for general fittings.

### Is bronze good for seawater and marine use?

Yes, particularly aluminum bronze (C954) and nickel-aluminum bronze (C630), which have excellent seawater corrosion resistance and are used for propellers, pumps, and valve components. Leaded bearing bronzes are less corrosion-focused, so match the grade to the environment.

### What tolerance can shops hold on a bronze bushing?

Turned and ground bronze bushings routinely hold bore diameters to a few tenths of a thousandth for a specified running or press fit. Call out the bore diameter, the fit class, the mating shaft size, and the surface finish, and the shop will confirm the achievable tolerance.

### What files should I send for a bronze part?

STEP, IGES, X_T, or a dimensioned PDF. Include the bronze grade (for example C932 or C954), bore and OD dimensions with fits, surface finish for bearing surfaces, the mating shaft material, and quantity.

## Related Materials

- [Brass](https://openspindle.com/materials/brass.md)
- [Copper](https://openspindle.com/materials/copper.md)
- [Stainless Steel](https://openspindle.com/materials/stainless-steel.md)
- [Alloy Steel](https://openspindle.com/materials/alloy-steel.md)
- [Aluminum](https://openspindle.com/materials/aluminum.md)
- [Delrin](https://openspindle.com/materials/delrin.md)

## Get bronze part quotes

Upload a drawing once and compare quotes from independent shops that turn and mill bronze bearings, bushings, and fittings.