Indexable Cutting Tools & Turning Inserts

Carbide inserts are a tungsten carbide / cobalt composite: tough, versatile and able to survive interrupted cuts, which is why they cover most steel, stainless and cast iron turning. Cermet inserts use a titanium carbide or titanium nitride base that resists chemical wear and built-up edge at high cutting speeds, giving a better surface finish on steel finishing passes — but they are more brittle and less forgiving of interrupted cuts.

Negative inserts such as CNMG and TNMG have 0° clearance and are double-sided, so they give twice the usable corners and high edge strength for rigid setups and heavy cuts. Positive inserts such as CCMT and DCMT carry a 7° positive clearance — the C in the designation — and cut with lower force, which is what you want on small-diameter work, internal boring, thin-walled parts and less rigid machines. The second letter of the code is the clearance angle: N is 0°, C is 7°, P is 11°.

The first letter is the shape (C = 80° rhombic), the second the clearance angle (N = 0°), the third the tolerance class and the fourth the chipbreaker and fixing style. Then 12 is the inscribed circle in millimetres — 12.7 mm — 04 is the thickness, 4.76 mm, and 08 is the corner radius, 0.8 mm. The inch ANSI code for the same insert is CNMG 432.

The rule is which part moves: turning feeds a single-point insert against a rotating workpiece and produces a continuous chip, while milling rotates a multi-tooth cutter against a stationary or fed part. The turning insert range covers the stationary-tool case. If your operation rotates the cutter instead of the workpiece, you need milling inserts and cutters — tell us the operation and we will point you to the right family.

You can physically clamp it, but you will not be happy with the result. Aluminum and other non-ferrous alloys need sharp, high-positive inserts with polished surfaces and no adhesion-prone coating, otherwise you get built-up edge and a torn finish. Steel needs a tough, coated grade that survives higher pressure and temperature. Grade and geometry should be chosen per material.

Yes — CBN and ceramic inserts are supplied for hardened steel above HRC 45, plus PCD inserts for aluminum and non-ferrous finishing. Send the workpiece material, hardness, depth of cut and machine rigidity and we will recommend the grade, edge preparation and starting cutting data.

Tooling is sourced from vetted tooling partners and inspected before dispatch. The grade, coating and geometry are confirmed against the quotation, dimensional reports and material certificates are provided on request, and each shipment is packed for transit. If a batch does not perform as confirmed, send us the batch reference and measurements and we will make it right.

The workpiece material and hardness, the operation (turning, boring, grooving, threading or milling), the machine and tool holder interface, the insert designation or a drawing / 3D model if it is a special, and the quantity you need. With those five points we can quote a matched insert, grade and coating instead of a generic one.

Quotations are normally issued within hours during business hours — email and WhatsApp reach us directly. Orders ship worldwide from Guangzhou, China with tracking, and payment terms are stated on the quotation. Trial quantities and mixed-item orders are both welcome.