Kuroda UPB-3S Boring and Facing Head

Agree with Andrew about boring heads not being able to run fast enough to get the benefits of carbide, HSS still has its place for certain things.

Forgot to say that for the trial cuts I used a 6mm square HSS toolbit that came with the boring head.

Andrew

I have to say I am quite envious of the comparatively low-profile of your Kuroda compared to my Boneham & Turner which takes up a significant amount of the daylight between my spindle and table.

My experience of the commonly available insert boring bars is that they have geometry designed for lathe work, and the additional stick-out and reduced clamping surface in a boring head inevitably results in vibration under "proper" cutting conditions or poor surface finish from low surface speed, making it a fools errand no matter what you try.

A friend of mine has had a lot of success using QCMT "Multi-Turn" Drilling, Boring and Turning inserts in a boring head on his CNC machine to finish out holes roughed with a spiral toolpath, which seem to give significantly more back rake compared to the more widely available ISO insert geometries... But unless you find yourself suddenly doing a lot of boring in harder materials it's unlikely to be worth the outlay.

For my sins I usually use brazed carbide boring bars unless the hole is quite large where I'd use HSS like yourself, for economy.

Edited By Jelly on 12/06/2023 00:12:27