General Purpose Thread Mills

General Purpose Thread Mill Series

The general-purpose catalog contains DHAM, DHBM and DHCM model groups. DHAM and DHBM tables include an effective-length field; DHCM tables list flute length. Use each series' own dimension drawing and specification table, since these fields describe different dimensions. Flute count is also listed by model: options differ between groups and sizes.

The catalog tables provide a starting point for selecting an assortment. For each purchase line, keep the series, model code, thread size and pitch together. Review the selected item's dimensions before choosing a holder or substituting a different model.

For example, the DHCM160P150 and DHCM160P150L rows share an M16 thread designation and a 1.5 pitch, but have different listed cutter diameters and flute lengths. Check each complete row and the feature clearance rather than ordering by thread designation alone.

How to Specify a Thread Mill

For an internal-thread application, check cutter diameter against the prepared bore and the complete tool path. A matching nominal thread size is not enough if the cutter, neck or holder cannot clear the feature. For a blind hole, include the unthreaded clearance and bottom geometry in the drawing review. State whether the drawing calls for an internal or external thread; the available catalog rows do not establish that every listed model is suitable for both.

Pitch, Length and Tool Access

Pitch is the distance between corresponding points on adjacent threads. Match it to the part specification and to the particular thread-mill model. Two tools listed for the same nominal thread size may have different pitches; they are not automatically interchangeable.

Distinguish effective length, flute length and overall length when comparing tables. The effective-length value should be read with its catalog drawing; flute length identifies the fluted section; overall length covers the complete tool. Neither a longer tool nor a longer fluted section alone confirms that the assembly will reach a particular thread depth.

Thread Milling or Tapping?

Thread milling uses a rotating cutter and a programmed tool path, while tapping uses a tap to form or cut the thread as it advances. The appropriate choice depends on the thread, workpiece, machine and production requirements. Before specifying a thread mill, confirm that the machine and control support the intended interpolation and that the program suits the selected cutter and thread form.

For applications involving hardened material, provide the material grade and actual hardness with the RFQ so the appropriate series can be reviewed. Do not replace one model solely because its nominal diameter is similar.

Prepare the Purchase Specification

For a trial or recurring order, identify the catalog model, quantities and drawing revision. Include any critical tool dimensions, sample acceptance requirements and required documents. If your assortment needs labels, barcodes or a specific packing format, send those requirements with the model list so they can be addressed in the quotation.

For a hardened-workpiece requirement, review the thread mill for hardened materials and provide the material condition and hardness with the RFQ.

Catalog Series, Product Views and Dimension Drawings

DHAM Series · R095

DHBM Series · R096

DHCM Series · R097

DHCM Series · R098

Catalog Model Specifications

Check each DHAM, DHBM and DHCM row against the required thread designation, pitch and tool dimensions.

Production Equipment Reference

The photographs below show production equipment and workshop operations used as manufacturing-reference material for carbide tooling enquiries. Process requirements are confirmed for the selected model and order.

Inspection and Measurement Equipment Reference

The photographs below show inspection and measurement equipment used when discussing drawing dimensions and order requirements. The inspection scope is confirmed for the selected order.

Frequently Asked Questions