Our website uses cookies and other technologies to ensure you get the best browsing experience.

You can change your cookie settings at any time.

Find out more on how we use cookies.

NPA 13/2020

New Indexable Milling Cutters with Round Inserts for Efficient 3D Surface Machining


ISCAR is expanding the ROUNDMILL family by introducing new milling cutters carrying one-sided round (button) inserts

The new cutters are available in endmill exchangeable heads and shell mill configurations. The cutters are intended mainly for machining 3D surfaces, especially the working surfaces of blades in turbomachinery.

The tool bodies of the cutters bear the designation FRMT … and are available in 40, 50 and 52 mm diameters – the most popular diametral values for blade manufacturing in the power generation industry.

There are two types of cutters with round inserts: FRMT-12 for 12 mm dia. inserts and FRMT-10 for 10 mm dia. inserts. The insert pocket of the FRMT mills features an advanced design that provides fail-safe insert indexes and ensures very rigid and reliable insert clamping which is of key importance in multi-axis machining for 3D surfaces, and when a cutting tool experiences rapid load fluctuation in different directions.

All the cutters have internal channels for coolant supply directed to the working cutting edge of the mounted inserts.


The RPHX single-sided positive round inserts have a specially shaped bottom and side surfaces used for indexing and to prevent the insert from rotating.

The inserts are available in two types:
  • RPHX - Precise
  • RPMX - Economical

There are also two types of insert cutting geometries:
  • MT - Recommended mainly for steel, ferritic and martensitic stainless steel (ISO P group).
  • HT - Intended mostly for austenitic and duplex stainless steel and high temperature alloys (ISO M and S groups correspondingly).

The new inserts are produced from the latest ISCAR carbide grades with the SUMOTEC post-coating treatment.

At the first stage, the RP...X inserts, which are intended for 5 indexes, are being introduced.

Inserts designed for 4, 6 and 8 indexes will be produced as special items per request.

The insert designation key code for ordering is as following:

Insert type
(H, M)
Insert diameter and thickness
(1003, 1204)
Insert cutting geometry
(MT, HT)
Number of indexes
(4, 6, 8)
Carbide grade number

The main application field of the new cutters is high-efficiency rough machining of 3D surfaces, particularly turbine blades in the power generation industry. The cutters also have applications in the aerospace and die and mold industries. In addition to rough profiling, these cutters successfully perform face milling, ramp-down milling and circular milling.

Cutting data
For initial cutting speed, refer to ISCAR’s recommendations regarding cutting speeds according to tool material grades.

Information about the range of feeds per tooth, the depth of cut range, and the maximum depth of cut as the function of an insert diameter and insert indexes, can be found in the following pages.


Face Mills for Productive Machining of 3D Surfaces of Blades in Turbomachinery
(1) Cutting diameter maximum
(2) Number of inserts
(3) Maximum ramping angle
(4) For adaptation see page (5) Insert identification

Round milling inserts with specially shaped indexing grooves

Insert size
Number of indexes
ap (max)
*Bold values relate to standard inserts with 5 indexes.

Max. Recommended Depth of Cut

The NPA13-2020's pdf file: View (PDF) or Download (ZIP)
© ISCAR LTD. Manufacturer of Metalworking Tools (Iscar.com) All Rights Reserved