Tool marks

Tool marks occur during milling, by the superposition of the feed movement of the workpiece and the circular use of the cutting tool knifes. This superposition leads to an undulating surface. The troughs are called 'tool marks'. The faster the feed movement and the slower the tool rotation, the longer the tool marks appear.

A larger number of knives on the cutting tool cannot mitigate this effect, because only one cutting knive shows on the surface because of the inaccuracies in rotation. The 'shorter' cutters make their part of the chip removal work, but do not show on the workpiece because of their shorter length.

By tools with centering clamping system like hydraulic chuck, shrink fit (shrink fit toolholder) or HSK, the inaccuracies in rotation can be reduced, so that all knives become visible on the surface. Then, the tool marks appear less deep and in much shorter intervals.

Exactly the same knife supernatants and a rotation inaccuracy of 0 is reached with jointed tools. With the help of a jointer, the cutters are continuously trimmed on the same supernatant during the entire milling process. On the workpiece surface, this shows in even less deep and closely spaced tool marks.

Complete removal of the tool marks

Alternative terms

  • knife marks
  • planer marks
  • chatter marks

Images

herkömmlich gespanntes Werkzeug
LEITZ
Hydrospannsystem
LEITZ
Hydrospannsystem mit Jointer
LEITZ