HSK does not have the rotational repeatability like CAPTO during tool changes.
Means nothing when milling.
Means a little when turning or boring a decent sized diameter with a decent sized tool.
Means a lot when turning or boring small diameters or using small boring bars.
Means a lot when using mini turrets which are available for CAPTO but not sure about HSK.
^^^ That's an excellent point - relationship between rotational repeatability of the connection versus using small boring bars / small diameter bored holes.
I think OP's title mentioned "... vs new KM on a milling lathe "
^^^ This seems interesting.
For new / newer MAZAK integrex(es) [integracies ??? ] for some reason they offer HSK as standard and Capto (in the case of a C-6 machine ) is about a $4000 upgrade factory ordered for a new build. KM is also an option offered even for new machines as an option.
Maybe what
@BOB-OO is getting at is the
NEW KM4X interface ~ which apparently (HSK) machines can be retrofitted for ?
Basic draw bar force for comparison of the different connections can make a real difference. (smaller machines and smaller in cut loads seems HSK would suffice. - other than the rotational repeatability that
@fmari --MariTool- mentioned. ).
I'm not sure exactly what the draw bar forces are exactly for different integrexes i.e. J-200 or i-100 vs. i-200 or i-300 or Mazak's much larger machines (like a INTEGREX e-670H) or for that matter the draw bar forces on the Okuma Multus machines or DMG Mori Mill turn machines of different sizes.
For Integrex (mill turn) there are instances when there is no lower turret and therefore the bending moment of turning tools is more critical - thinking longer flash tooling type - 3 turning tools on one tool holder (indexable) at the B axis milling spindle (axis). Seems Capto would be the most secure also ? BUT not sure how that would theoretically or practically compare to the NEW -Newer- Newish KM X4 ...
The KM 4X being a roughly 4X multiplier of the initial draw bar force.
I.e. 20KN (Killo Newton) draw bar force being multiplied to a 80 KN clamping force at the connection.
That would be 4500 lbs draw bar force multiplied by 4 (ish) 18,000 lb draw bar force, approaching the maximum clamping force (for example for a C-6 interface - by comparison ).
Wonder if or how the KM4X jams or not ?
It's new to me so maybe I dig about ...