Quote Originally Posted by alanambrose View Post
On a similar topic, if I were to buy a new mill, what spindle taper should I look at? I'm seeing old R8 anglophile but MT / BT / HSK on the continent?

I appreciate this article is a bit serve serving, but reading between the lines, I'm getting an HSK buzz :)

https://www.sandvik.coromant.com/en-...selection.aspx

Alan
Depends really on how ridged the machine and how aggressively you want to cut, plus how deep your pockets are.?
HSK is far better than R8, MT, and to a lesser degree ISO/SK or BT, etc. BUT the holders cost nearly twice the price of BT so if you don't need the extra rigidity HSK offers then you'll have more money for BT holders.

Also, need to consider the strength of the machine, the main advantage of HSK is the rigidity it provides allowing more aggressive cuts to be made but if the machine doesn't match the taper what's the point.?