Boring Bar, 3/8" Indexable, 80 Deg HSS Diamond Inserts, A R Warner Kit #13

This Arthur R. Warner Co. precision tool holder kits use high speed steel or carbide inserts. These are production quality tool holders that are made in the USA. LEARN MORE

The minimum boring diameter is 0.330".

The Arthur R. Warner Co. is a family-owned American manufacturer of high speed steel products with specialization in cutting, shaping, pre-grinding, heat treating, and finish grinding of premium grades of flat high speed steel. Their quality is excellent and LittleMachineShop.com is proud to carry their products.

T-15 is a grade of cobalt tool steel, which offers the highest hardness of most common high speed steel grades.

This heavy-duty, high-speed steel grade offers maximum cutting-edge endurance and wear resistance due to its high Vanadium content. The Cobalt content additionally lends it high temperature hardness and resistance to tempering.

We are big fans of High-Speed Steel. Find out why... What's So Good About High-Speed Steel?

Make sure you get the correct inserts and retaining screws for your indexable turning tools.

Our chart of indexable inserts shows which inserts and which screw to use with each of our indexable tools.

Here's a video that talks about high speed steel tooling.