Milling


With Sandvik Coromant, a range of anti-vibration milling adapters for facemills and square holder facemills are standard off-the-shelf items.

In our stocked assortment we have adapters with cutter pilots (both metric and inch) from Æ 40 mm and Æ 3/4". The modular coupling at the back end is Coromant Capto or Varilock. Using these adapters instead of a stub arbor you can reach down into a cavity, or mill away material from the side of a shoulder.

If none of our standard adapters are suitable, contact us about a special adapter. As special tools we also make adapters for slitting cutters. We even have built-in dampers in large sidemills and long-edge cutters (see below).

Working with rotating tools, is a lot different from turning with a boring bar in a rigid tool post, but most of the conditions for successful operations are the same ;

  • Shortest possible arbor length.
  • Largest possible arbor diameters, but not larger than the minimum cross-section in the spindle nose connection (tapered down towards the cutter is good).
  • Minimum weight (smallest possible diameter) of the cutter to reduce the kinetic energy in a possible vibration.
  • Double positive milling cutter (see below)
  • Coarse pitch cutter to slow down changes in the cutting force directions.
  • A higher feed per tooth may give a constant preload on the machine tool spindle and prevent it from using the play in its bearings.

The seat pockets in a double positive milling cutter (3), are angled positive relative to both the axial and radial feed directions. With positive inserts in these pockets, the deformation of the chip will be minimal, and hence the cutting force as low as possible. In the figure below the double positive cutter is compared with a double negative cutter (1) and a positive-negative cutter (2).

Even four inserts can be too many. Reduction to only two inserts, will often make it possible to make a significant increase in the axial depth of cut.

Insert pockets that are not in use can be porotected by worn out and ground down inserts.



Special Tool example :

Long Edge milling cutter Æ 100x 210 mm with built-in damper and integrated ISO taper. (Requires a solid machine and a rigid spindle interface).
 
Silent Tools® is a definition of tool holder made to reduce vibrations due to a damper inside the tool body and is a trade mark of Teeness ASA. Damped boring bars are designed for high productivity, close tolerances and overhang beyond 4 x the bar diameter.