Sumitomo U102043 Insert Screw T8 Torx M2.5 X 0.45

Product Description

The SUMITOMO U102043 is an insert screw designed to secure indexable cutting inserts to boring bars and other indexable toolholders. It uses a T8 Torx drive with an M2.5 x 0.45 thread, providing consistent clamping force against the insert seat. The overall length measures 0.215 inches and the head diameter is 0.130 inches. This screw is part of the ANSI-ISO series and is the hardware that holds precision carbide inserts in place during turning and boring operations. Machinists and toolroom technicians install these during insert changes on CNC lathes and manual turning equipment.

This insert screw is used in boring bar applications where ANSI-ISO-style indexable inserts are employed. It is suited for production turning environments and job shop settings running standard insert geometries on CNC or manual lathes. The T8 Torx drive reduces cam-out risk during tightening, which is particularly relevant in confined boring bar pockets where access is limited. Replacement of this screw is typically part of routine insert-change maintenance to ensure proper seating and prevent insert movement under cutting loads.

Key Features

• T8 Torx drive reduces cam-out during tightening in tight tool pockets
• M2.5 x 0.45 thread matches ANSI-ISO boring bar insert seats
• Overall length of 0.215 inches fits standard insert pocket depths
• Head diameter of 0.130 inches for proper insert clamping coverage
• Compatible with a wide range of CCMT, DCMT, TCMT, TPMT, VBMT, and WPMT insert styles
• ANSI-ISO series for broad toolholder applicability

Compatibility

Compatible with the following indexable insert styles: CCMT 21.51, CCMT 32.52, CPMT 21.51, CPMT 32.52, DCMT 21.51, DCMT 32.52, DPMT 21.51, DPMT 32.52, TCMT 21.51, TCMT 32.52, TPMT 1.81.51, TPMT 21.51, TPMT 32.52, VBMT 221, VBMT 332, and WPMT 21.51. Suitable for inserts with inscribed circle sizes of 0.250 inches and 0.375 inches. Designed for use with indexable boring bar toolholders in the ANSI-ISO series.

Installation Notes

Insert screws are installed and removed by machinists or toolroom technicians during routine insert indexing or replacement. Always power down and lock out the spindle before accessing the tool pocket. Use a calibrated T8 Torx key or driver and follow the toolholder manufacturer's recommended tightening procedure to avoid overtorque, which can strip the thread or crack the insert. Inspect the screw threads and seating surface for wear or damage each time inserts are changed.