How to write a brass parts requirement that gets accurate quotes

By Manoj Khande, Founder, BrassRoute · 11 October 2026

Most slow or wildly different quotations have the same cause: the requirement left something out, and every factory filled the gap with its own guess. A clear requirement takes ten minutes to write and saves a week of questions.

This is the list we suggest to buyers who post a requirement on BrassRoute. It works just as well in an email to a manufacturer you already know.

1. A drawing or a sample, not just a name

"Brass insert M6" describes hundreds of different parts. Send a dimensioned drawing (PDF is fine, a STEP file helps for complex shapes). If you have no drawing, send clear photos of a sample with a scale in the picture and the key sizes written down: overall length, outside diameter, thread, hole size, knurl type. Say whether the manufacturer may suggest small changes that make the part easier to make.

2. The material grade, by its standard

"Brass" is a family of alloys, and the grade changes both price and performance. Name the grade and the standard you buy to. Common ones for machined and forged parts:

• CW614N (CuZn39Pb3) under EN 12164: the usual European free-machining rod for turned parts.
• C36000 under ASTM B16: the free-cutting brass most used in North America.
• CW617N (CuZn40Pb2) under EN 12165: forging stock for hot-forged bodies such as valves and fittings.
• IS 319: the Indian standard for free-cutting brass rods and sections.

If the part touches drinking water, or is going to a market with limits on lead, say so at the start. It usually means a low-lead or lead-free grade, which costs more and machines differently, so a quote based on ordinary free-cutting brass will not be valid. If you do not know the grade, describe the use and ask the manufacturer to propose one in writing.

3. Threads, written out in full

Thread mix-ups are the most common reason parts are rejected. Write the thread standard as well as the size:

• Metric (ISO): size and pitch, for example M20 x 1.5, with the tolerance class if you need one.
• BSP parallel (ISO 228, written G) and BSP taper (ISO 7, written R or Rc). They are not interchangeable for sealing.
• NPT (ASME B1.20.1), the taper pipe thread used in North America.
• PG threads, still used on some cable glands.

Say whether each thread is male or female, and its length.

4. Tolerances that match the job

Mark tight tolerances only where the part needs them, and state a general tolerance for everything else. Many drawings use ISO 2768 classes (fine, medium, coarse) for this. A tolerance tighter than the part needs raises the price and the rejection rate without making the part better.

5. Finish and plating

State the finish: natural brass, nickel, tin, chrome, silver, or another. Give the plating thickness in microns if it matters, and mention any salt-spray or appearance requirement. Say if the part must comply with RoHS or REACH, so the manufacturer can confirm it for the grade and plating offered.

6. Quantity, honestly

Give the quantity for this order and, separately, your expected yearly use. Factories price a one-time 2,000 pieces very differently from 2,000 pieces every month. If you want prices at several quantities, list them. Inflating the number to get a better price only produces a quote that changes later.

7. Delivery place, date and packing

Give the destination city and country, the date you need the goods, and the delivery term you want quoted (for example FOB an Indian port, or delivered to your door). Mention packing needs: bulk in cartons, bagged in counted lots, labelled with your part number, palletised.

8. Testing and documents

List what must come with the goods: material test certificate, dimensional inspection report, plating report, a first-article sample before the full run, or inspection by a third party. Asking for these after the order is placed is where disputes start.

A checklist you can copy

• Part name and what it is used in
• Drawing or sample photos attached
• Material grade and standard
• Threads: standard, size, pitch, male or female
• General tolerance and any critical dimensions
• Finish or plating, with thickness
• Quantity now and expected per year
• Delivery place, date needed and delivery term
• Packing and labelling
• Certificates, samples and inspection needed
• Target price, if you have one

What happens on BrassRoute

The requirement form on BrassRoute asks for the product, quantity, material or grade, delivery location and the date you need it, and our team reads each requirement before it goes to manufacturers. Posting is free for buyers. BrassRoute is a marketplace and not a manufacturer: you agree the price and terms directly with the factory you choose, and you should check a supplier's samples and documents yourself before placing an order.

Sources

1. Free-Cutting Brass (Alloy C360), Copper Development Association

Standards are revised from time to time. Check the current edition of any standard you name on a drawing or purchase order.