Ringwood-based Horn Cutting Tools Ltd (www.phorn.co.uk) has introduced two grooving systems for the internal machining of bores.

System 209 is intended for bores 16mm in diameter and above, while System 216 is for bores greater than or equal to 20mm in diameter.

Both systems make use of tool-holders with internal cooling. A robust shank with elliptical cross-section of the boring-bar neck ensures high-performance damping, says the company. The ground shanks, of g6 quality, are available in left- or right-hand types.

Coolant flows from a nozzle in the clamping finger and from the side of the tool-holder.

The two jets cool the cutting zone and remove chips from the inside of the workpiece. Precision-sintered indexable two-edged inserts with cutting widths from 2 to 6mm are available in geometries 5, 1A and KF for cutting medium-strength materials.

All three geometries are said to offer good chip control and targeted chip breaking, even on long-chipping materials.

The System 209 tool-holders with a shank diameter of 16mm allow retraction distances up to 30mm in conjunction with a grooving depth of 3.5mm.

For bores with a diameter of 18mm or above, a more-stable shank diameter of 20mm (also with a retraction distance of 30mm) can be used to achieve a grooving depth of 5mm.

The System 216 tool holders, with a shank diameter of 20 or 25mm, enable grooving depths down to 7mm at a projection length of 2xD.