Thread Measuring Wires — Best-Size Wire Diameters for ISO Metric M Threads (0.2 – 8 mm pitch)

Documents

Shipments are backed by Mill Test Certificate (MTC), Dimensional Report, Salt Spray Test Report on request, with full batch traceability from raw material to finished product. Quality management follows the owner-confirmed compliance list: ISO 9001:2015, RoHS, REACH. Exact document sets are confirmed on the order.

Quotation

• The fastener family (Thread Measuring Wires — Best-Size Wire Diameters for ISO Metric M Threads (0.2 – 8 mm pitch)) plus the standard designation from your drawing — DIN / ISO / JIS / ASTM / ANSI, or a drawing for custom parts.
• Size (diameter and length), thread type (metric or inch), property class or grade, and coating or finish.
• Quantity per size and your target delivery date.
• Destination country, and any required documents (for example a mill test certificate) so the quote includes them.

Sample & supply

Minimum order quantity is 10,000 pieces. Stock items run 3–7 days. Quantities or variants outside the standard range are confirmed at quotation.

Storage & shipping

Parts are packed for export and shipped factory-direct to buyers in Europe, Asia, the Americas and the Middle East. Store fasteners dry and protected until installation, and keep coated parts in their packaging until use; specific packing and preservation requirements can be stated on the order and confirmed at quotation.

Why must the wire size match the pitch, and how do I use the three-wire reading once I have it?

Because the wire diameter enters the measurement arithmetic directly. Three wires sit in the thread flanks and the micrometer reads over two of them; the pitch diameter is backed out of that reading minus a geometry term built from the pitch and the wire diameter. When the wire is best size — contacting the flanks exactly at the pitch line — the flank angle error cancels and the arithmetic is simple; when the wire is oversize or undersize, the contact point climbs or drops the flank, the flank half-angle leaks into the result, and a perfectly good thread can read out of tolerance (or a bad one pass). That is what the collected chart pins down: per ISO 16239, each metric pitch from 0.2 to 8 mm has one correct wire — 0.5 mm pitch takes 0.289 mm wires, 1.25 mm takes 0.722, and so on; the source also prints the general rule (P/(2 cos α/2)) so a non-tabulated symmetric form can be derived. In practice: measure over the three wires, subtract the constant for the pitch/wire pair, and compare against the pitch-diameter limits of the thread standard (see this catalog's metric thread dimension pages for the 6H internal limits). Keep wires clean and matched — one worn wire skews the whole reading. Wire tolerance class, calibration certificates and measurement uncertainty budgets are beyond the chart — per RFQ.

What is the MOQ and lead time for threaded parts and gaging hardware on this standard?

The minimum order quantity is 10,000 pieces. Stock items ship in 3–7 days; non-stock items are confirmed at quotation. Confirm the exact schedule against quantity and size mix at quotation.