When machining, selecting the correct carbide insert shape is crucial for optimizing performance, tool life, and achieving the desired results. Each insert shape has its unique strengths and applications. Here’s a guide to help you choose the suitable carbide insert based on your specific machining needs, using information from Millstar’s Total Carbide Insert Solutions.
Square Inserts
Strength and Economy: Square inserts offer a very strong 90° corner, providing excellent economy with up to 8 cutting edges on double-sided inserts.
Best For: These inserts are ideal for rough facing operations, particularly on castings, forgings, and rough-sawed blanks.
Limitations: Square inserts are unable to turn or face up to a shoulder unless used in a toolholder with a minimum 5° lead angle. High radial forces can push against the workpiece during turning, so they should always be used in a stable setup.
80° Diamond Inserts
Versatility and Popularity: The 80° diamond insert is the most popular shape due to its versatility. It has a strong cutting edge and secure seating in the insert pocket.
Best For: These inserts are suitable for turning and facing operations, with opposite 100° corners providing maximum economy in roughing applications.
Limitations: With only 5° of clearance between the trailing side of the insert and the workpiece, chip jamming can occur when boring.
80° Corner Trigon Inserts
Economy: This insert offers increased economy compared to CNMG-style inserts.
Best For: These inserts are typically used for moderate cut and feed rate depths, making them a good choice for general-purpose machining.
Limitations: The seating is not as stable as CNMG-style inserts, and they cannot handle as deep a depth of cut.
Triangle Inserts
Versatility: Triangle inserts are highly versatile and suitable for turning, facing, boring, copy turning, and basic profiling.
Best For: They are an excellent choice for general boring due to their stable seating in the boring bar pocket and extra side clearance, which reduces the risk of chip jamming.
Limitations: The edge strength of triangle inserts is weaker than 80° diamond-shaped inserts.
55° Diamond Inserts (D-Shape)
Profile Turning: The 55° diamond insert is generally the first choice for profile or copy turning applications, capable of “in-copy” (plunge turn into a smaller diameter) at a 30° angle.
Best For: These inserts are ideal for machining near the tailstock or live center.
Limitations: They have weaker edge strength than triangle inserts, and the cost per edge is higher than most other turning inserts.
35° Diamond Inserts (V-Shape)
Intricate Machining: The 35° diamond insert is the go-to choice for intricate shape copy turning and can “in-copy” at angles up to 49°.
Best For: It is ideal for working extremely close to the tailstock or live center.
Limitations: This is the weakest insert shape in terms of edge strength, so the depths of cut and feed rates must be lighter. It also has the highest cost per edge.
Conclusion
Choosing the right insert shape is critical to the success of your machining operation. By understanding the strengths and limitations of each insert shape, you can optimize your machining processes for better efficiency, accuracy, and cost-effectiveness.
At Epic Tool, we offer a comprehensive range of carbide inserts from the Total Carbide brand from Millstar Canada, designed to meet the diverse needs of machinists. Contact us today to learn more about how our carbide insert solutions can enhance your machining operations.
