Copper strip specification for engineering drawings and RFQs

This handbook is an authoritative, non‑proprietary reference for engineers who must create or evaluate a copper strip specification for engineering drawings and RFQs. It explains temper designations, tolerances, grain direction callouts, surface finish metrics, plating units and inspection notes so you can write clear, testable drawing notes and procurement requirements.

Purpose, scope, and how to use this copper strip specification for engineering drawings and RFQs

This section defines the handbook’s intent and explains how to use the content when preparing prints or requests for quotation. The goal is a pragmatic, vendor‑agnostic approach to a copper strip specification for engineering drawings and RFQs so procurement, manufacturing and quality teams share a single interpretation of requirements. Use the guidance below to: 1) compose a one‑page callout block for drawings, 2) build RFQ checklists that suppliers can price against consistently, and 3) create inspection acceptance criteria for incoming lots.

Quick-reference spec summary (one-page callout template)

Pasteable callout templates make it easy to apply consistent requirements across drawings. A compact copper strip specification for drawings and RFQs should include material grade, temper, thickness/width tolerance class, grain direction, surface finish, plating target and acceptance, flatness/camber limits, edge condition and packing/marking notes. Below is an example callout template engineers can adapt:

• Material: Copper, UNS C10100 (or specified alloy)
• Temper: H04 (see note 1)
• Thickness: 0.25 mm ±0.02 mm (tolerance class)
• Width: 10.0 mm ±0.1 mm
• Grain: RD parallel to long axis (see symbol)
• Surface: Ra ≤ 0.8 µm; plating: Ni 3.0 ±0.5 µm (XRF)
• Flatness/camber: ≤ 2 mm/m
• Edge: Deburred, radius 0.2 mm where indicated
• Packaging: coil on core, anti‑tarnish separator, lot label

Units, notation and conventions (µm, µin, MPa, H temper notation)

Consistent units and notation prevent misinterpretation. On drawings and RFQs prefer metric SI units with imperial equivalents in parentheses where needed. Specify plating and roughness in micrometers (µm) and include µin equivalents if suppliers commonly quote imperial values. Use MPa for tensile/yield, and give hardness units explicitly (e.g., Vickers HV or Rockwell). When referring to temper, use the temper notation (for example H01, H04) alongside a short definition so the buyer and supplier share the same expectation. If you maintain a copper strip and foil specification for procurement and shop drawings folder, include these unit‑conversion tables there for quick reference.

Material tempers: overview and convention (annealed → spring)

Temper designations define the material’s mechanical condition. For copper strip, common states range from fully annealed (O) through light work‑hardening (H01/H02/H04) up to spring tempers used for high‑spring applications. A clear copper temper specification and a short table of expected tensile or hardness ranges removes ambiguity in procurement. When you call out a temper on a drawing, include either a recognized designation (e.g., H04) or a testable property requirement (e.g., 0.2% offset yield ≥ X MPa) if precise performance is required. This is especially important where the spec references copper temper designations and mechanical property conventions (annealed → spring).

Temper abbreviations and accepted wording for drawings

Use concise, repeatable wording on prints: e.g., “Temper: H04 per note — tensile 260–320 MPa” or “Temper: O (annealed).” Avoid proprietary trade names. If a hardness or tensile requirement is essential, add the test method and sample size for verification in the inspection plan. For practical help, see how to call out copper strip temper (H01, H04) and hardness on drawings for example phrasing and notes you can paste directly into your RFQ.

Thickness and width tolerances: classes, tables and examples

Specify tolerance classes appropriate to the part function and manufacturing realities. Tighter tolerances increase cost; the goal is to select the loosest tolerance that still meets functional requirements. Provide a table on the drawing or RFQ that maps nominal thickness and width to the permissible ± tolerances and reference the measurement method (micrometer, caliper, or optical gauge). Including thickness and width tolerance tables for strip and foil in the drawing or an appendix clarifies expectations and speeds supplier responses.

How to calculate permissable variation and specify in a print

Show worked examples converting tolerance classes into ± values. For example, a 0.30 mm nominal thickness in tolerance class T2 might read as 0.30 mm ±0.03 mm. Include measurement temperature and instrument accuracy in the note to ensure repeatable inspection results. Also state whether tolerances apply per coil, per cut length, or per finished piece to avoid interpretation differences.

Grain direction: definitions, symbols and why it matters

Grain direction (rolling direction) strongly affects forming, spring‑back and fatigue life in copper strip. Indicate grain direction with a standard arrow or “RD” callout where orientation is critical. When forming parts like spring fingers, specifying grain parallel to the long axis improves bend performance and reduces risk of cracking. If your team needs a short reference on best practice for grain direction callouts on copper strip for forming and spring fingers, include it in the drawing notes and RFQ so suppliers know when orientation is mandatory.

Best-practice callouts for grain direction on prints and RFQs

Use a concise symbol and text: for example, an arrow with label “RD → (grain direction) — required for forming.” When grain orientation is optional, note “grain direction not controlled.” If a sample is required to demonstrate orientation, state that in the RFQ and include acceptance criteria for grain verification. These practices align with broader expectations in an engineering copper strip spec — tolerances, temper, grain direction — and reduce fitment failures in stamped or formed parts.

Surface finish and roughness: specifying Ra, Rz (µm/µin) and acceptance

Surface finish requirements depend on contact function, appearance and adhesion of platings. Specify roughness using Ra (arithmetical average) or Rz and include units (µm). For electrical contact surfaces, a smoother finish (lower Ra) may be required to ensure reliable mating and plating uniformity. Indicate whether roughness applies before or after plating and provide acceptance tolerances in the drawing note. Where helpful, link to surface finish, roughness (µm/µin) and plating thickness callouts for copper strip — test methods and units so suppliers understand how you expect measurements to be taken and reported.

Surface finish testing methods and typical inspection notes

Reference standard test methods and instruments — for example, a profilometer measurement per the cited method — and require the supplier to report the average and maximum values across representative locations. Add an explicit statement such as “Surface finish Ra ≤ 0.8 µm measured per profilometer at three locations; report measurement locations and values.” This reduces misunderstandings about whether measurements are taken pre‑ or post‑plate.

Plating and coating: thickness units, test methods and specified tolerances

For plated strip, define the plating system, target thickness in micrometers (µm) with a permitted tolerance band, and the test method (XRF, coulometric or cross‑section). State if the stated thickness is inclusive or exclusive of base metal and whether any intermediate layers are required. Clear plating callouts reduce disputes on acceptance and improve first‑pass yield. When useful, refer suppliers to surface finish, roughness (µm/µin) and plating thickness callouts for copper strip — test methods and units so they can align their measurement and reporting processes with your requirements.

Conversion and reporting: how to show plating tolerances on a drawing

Use a standard callout format: e.g., “Plate: Ni 3.0 ±0.5 µm, test: XRF per note — measure three positions per coil and include detailed report with lot shipment.” If dual units are needed, show µm first and µin in parentheses. Specify whether the supplier must include calibration certificates for XRF or coulometric equipment in the test report.

Flatness, camber and camber measurement methods on receipt

Flatness and camber are important for automated feed systems and forming. Define camber as the maximum lateral deviation per unit length and state a measurement method — for example, supported on a flat surface with a gauge or optical scanning. Include acceptance limits on drawings so receiving inspection can quickly determine conformance. Link these expectations to camber/flatness inspection methods and acceptance limits in your inspection plan to ensure consistency across suppliers.

Typical flatness specs and pass/fail examples

Provide tabulated examples such as allowable camber ≤ 1 mm/m for thin foils and ≤ 2 mm/m for thicker strip. Show example acceptance language: “Camber ≤ 1.5 mm per 1000 mm length; measure with edge support method and report as part of inspection records.” Include a note about how camber tolerances may change for narrow, long strips used in automated feeders.

Edge conditions: square, deburred, fully rounded — callout language and functions

Edge condition affects handling, assembly and plating coverage. Standard options include square, deburred, chamfered or fully radiused edges. State the required edge finish on the print and, where necessary, call out the radius or chamfer dimension. For parts that contact delicate surfaces or require sliding motion, a specified radius reduces wear and stress risers.

When to require special edge prep (spring fingers, sliding contacts)

For spring fingers or sliding contacts, require radiused edges (e.g., R0.2) or chamfers to prevent digging into mating parts and to improve fatigue life. Note any additional deburring or tumbling that must be completed before plating to avoid entrapment of plating remnants or debris.

Mechanical properties, hardness notes and conversion to design requirements

Link temper designations to measurable mechanical properties such as tensile strength, yield and elongation. If a temper designation alone is insufficient, specify the required testable property and test method (e.g., tensile per ASTM E8 or hardness HV per a defined load). This ensures that supplier certification and incoming inspection tests can demonstrably verify conformance. When drafting notes, reference copper temper designations and mechanical property conventions (annealed → spring) so procurement and test labs use consistent acceptance criteria.

Specifying hardness vs specifying mechanical property values

Where function depends on elastic behavior or spring force, specify a hardness or tensile/yield target rather than only a temper. For example: “Temper H04 or tensile 260–320 MPa and elongation ≥ 10%.” Include the test standard and sample size required for lot acceptance. Practical phrasing and sample sizes help reduce back-and-forth with suppliers over test method and pass/fail interpretation.

Inspection, sampling plans and acceptance criteria for incoming lots

Define the minimum inspection requirements you expect from suppliers and what you will perform on receipt. Specify the sampling plan (e.g., ANSI/ASQ Z1.4 levels), required test reports (dimensional, plating thickness, surface finish, hardness), and mandatory documentation such as certificate of conformance and lot traceability. Clear expectations minimize delay and disputes at receiving.

Nonconforming material: reporting, corrective action and disposition notes

Include language on acceptable disposition: return to vendor, rework with prior approval, or use with concession under documented agreement. Require suppliers to report nonconforming conditions discovered pre‑shipment and to provide corrective action plans when significant deviations occur. Adding explicit timelines for corrective action responses reduces schedule risk when a lot is rejected.

Packaging, preservation and marking instructions to include on prints/RFQs

Packaging preserves material condition and traceability. Specify protective coatings or anti‑tarnish separators, coil or reel packaging methods, and mandatory lot marking or barcodes. Indicate whether preservative oils must be removed before plating and whether separation layers are required between layers of strip to prevent scratching. Also require a basic packing list and lot label to speed receiving verification.

Example drawing callouts and a ready-to-use RFQ checklist

Complete, copy‑paste callouts accelerate consistency. Provide three examples: an annealed foil callout for shielding, an H04 spring finger strip with grain and hardness targets, and a plated contact strip with plating thickness and XRF reporting requirements. Provide an RFQ checklist that lists mandatory items suppliers must return with quotes (material spec, temper, dimensional tolerances, plating spec and test method references, sample availability, lead time, packaging and inspection records). These example blocks are the practical core of a copper strip and foil specification for procurement and shop drawings.

Example A: Annealed foil — callout and acceptance criteria

Sample note: “Material: Copper C10100, temper O (annealed). Thickness 0.05 mm ±0.005 mm. Surface finish Ra ≤ 0.5 µm pre‑plate. Packaging: reel, anti‑tarnish separator. Report: dimensional check and certificate of conformance with shipment.”

Example B: H04 spring finger strip — callout and test needs

Sample note: “Material: Copper, temper H04. Thickness 0.30 mm ±0.02 mm. Grain: RD parallel to long axis. Hardness: Vickers 120–160 HV (or tensile 260–320 MPa). Plate: Ni 3.0 ±0.5 µm (XRF). Inspection: hardness and plating thickness report for each lot.” This type of example directly supports how to call out copper strip temper (H01, H04) and hardness on drawings and shows the measurement expectations for incoming inspection.

Appendix: conversion tables, common note library, and quick reference standards

Include SI/imperial conversion tables for common units (µm ⇄ µin, mm ⇄ inches, MPa ⇄ psi) and a library of standard note text for temper, plating, roughness, edge condition and packaging that can be copy‑pasted into drawings or RFQs. Also list non‑proprietary test method references for inspection (e.g., profilometer standards, XRF calibration notes, tensile/hardness standards) so suppliers know which methods you accept.

Using the templates, callouts and examples in this handbook will help you produce a clear, testable copper strip specification for engineering drawings and RFQs that reduces ambiguity, minimizes supplier questions and improves first‑pass acceptance rates at receiving inspection.