I don't recall the original poster asking about boring bars/boring tools.
Could you explain to me please how to bore a taper in this manner?
The projection/cantilever of the tool from its holder is the same at the start/top/front of the hole as it is at the finish/bottom/back.
Is the header not about 'Lathe tool sharpening' and whats a boring bar?
Since some one else posted tipped tools and Glanze its my own findings done in the real world who uses a lathe daily to provide bread and butter.
Next time bore a deep hole measure front and back, tool visually veers off as in flex gradually veering more out down inside hole, leave it to run cuts a groove. Send It down several times and each pass takes a cut more so at the end or breakout until flex gone out the tool. Equally may chaff/vibrate. Theory is one thing in practice is a different matter I have other expensive tools that do the same but not similar others.
Also had a part off tool, 16 square slightest touch and visually see tool deflect downwards then in to chaff mode, terrible tips supplied and still useless with branded tips. Given away a couple of years ago.
The ER and IR tips aint bad from Glanze readily available come quick next day when you cant find best quality at right price, there are a lot better.