MIR Series 29 Degree Solid Carbide Micro Internal ACME Threading Bars for Small Bore Machining

They are solid carbide right-hand tools for machining compatible 29° ACME internal thread profiles in small or restricted bores. Typical components include lead nuts, adjusting nuts, compact actuators, positioning mechanisms and other power-transmission parts.

A29 identifies the 29° included cutting profile used for compatible ACME threads. It should not be substituted for a 30° trapezoidal, 55° imperial or 60° metric threading tool.

The standard range includes 16, 14, 12, 10, 8, 6 and 5 TPI models. Each model is intended for its stated threads-per-inch value, so the required TPI must be confirmed before ordering.

Standard models cover cutting diameters d1 from Ø3.9 to Ø11.9 mm, clearance lengths L1 from 15 to 50 mm, shank diameters from Ø4 to Ø12 mm and overall lengths from 50 to 100 mm.

No. The d1 value is a tool dimension. Minimum bore suitability depends on the complete thread geometry, minor diameter, thread depth, entry clearance and tool retraction path, so the component drawing should be checked before selection.

The listed MIR A29 models are right-hand internal threading bars. If the machine layout or toolpath requires a left-hand configuration, submit the drawing and machining direction for a custom-tool review.

Confirm the complete ACME thread designation, General Purpose or Centralizing form where applicable, nominal diameter, TPI, thread class, hand, required thread length, bore geometry and available clearance. Then select the matching TPI and the shortest practical L1.

The standard tools are TPI-specific and should be matched to the required thread. Do not use a 16-TPI model to cut a 14-, 12-, 10-, 8-, 6- or 5-TPI thread.

Choose an L1 long enough to reach the full thread and provide safe entry and retraction clearance. Use the shortest practical reach because excessive overhang reduces rigidity and may increase chatter or thread-form error.

Minimize tool overhang, clamp the shank securely, verify center height and runout, and use a multi-pass threading cycle with controlled infeed. Start conservatively and adjust speed, pass depth and the finishing passes according to material, rigidity and thread size.

Suitable coolant or air-assisted chip evacuation is recommended when the material and machine permit it. Direct the flow toward the cutting zone and confirm that chips can leave the bore without being recut or packed into the finished thread.

Verify the spindle direction, tool hand, programmed TPI, thread start position, infeed method, final depth, relief or runout space and retract path. A dry run or single-block check is recommended for a new program.

Yes. Custom thread diameter, TPI, thread form, cutting diameter, clearance length, shank diameter, overall length, carbide grade, coating and cutting geometry can be reviewed according to drawings or samples.

Please provide the standard model or component drawing, complete ACME designation, nominal diameter, TPI, thread class and hand, bore dimensions, thread length, workpiece material, quantity and any coating, marking or packaging requirements.

Yes. The standard minimum order quantity is 10 pieces, and mixed-model or sample requirements can be reviewed according to the selected TPI values, sizes and available stock.

Yes. Laser marking, labels, packaging and distributor private-label requirements can be supplied subject to order quantity and artwork confirmation.

In-stock standard models can usually be dispatched within 1–3 working days after order confirmation. Custom tools require separate lead-time confirmation based on geometry, TPI, coating, quantity and production requirements.