What is brass?

It is known as free-machining brass, with a lead content of about 3 %. It machines at high cutting data with little wear and goes into fittings, valve parts, bushes, inserts, contact parts and small turned parts in volume. You buy it as round bar, hexagon and sections. Drinking-water applications and some electronics set stricter limits on lead; the drawing then names a low-lead or lead-free grade such as CuZn21Si3P (CW724R).

What does the standard say about brass?

Rod for free machining is covered by EN 12164. The material number follows the European numbering system for copper alloys: C stands for copper, W for wrought material, and the final letter gives the alloy group, N for copper-zinc-lead. Which lead content is allowed depends on the application and the rules that apply to it, such as drinking-water requirements and RoHS. Those rules change, so the drawing or the customer has to fix the grade.

How does brass behave in the shop?

Brass machines quickly but costs a lot per kilo, so material can be the largest cost item. That makes the bar diameter important: buying one size up costs relatively more in brass. Swarf and offcuts have resale value if you keep them separate. Whether you offset that return in the estimate is a house convention; if you do, record the price you assumed. The copper price moves, so a brass price without a date says little. Lead-free grades usually machine more slowly and wear tools more.

What is brass often confused with?

Brass is not bronze: bronze is copper with tin, such as CuSn8 for plain bearings, and machines differently. CuZn37 is another matter: it contains no lead, cold forms well and machines with long chips.

How do you see brass in Blake?

In Blake your purchase price for brass bar or hexagon sits in the material catalogue with source and date, and the history of that price stays visible. You can see how old the price you are working with is. Material is its own line in the estimate, apart from machining. More on materials.