Why are there divot marks where the bit plunges, and why do V-bit tips keep snapping?

Why this happens

A straight vertical plunge forces the center of the bit, which has zero surface speed, to push through material. End mills leave a burnished divot; fragile V-bit tips can simply snap, especially in hardwood. Slow plunge rates make it worse by dwelling.

The fix

1. Use ramps. In the Pocket toolpath form, check Ramp Plunge Moves and enter a ramp distance. In the Profile toolpath form, use the Ramps tab (the types are Smooth, Zig Zag and Spiral). The bit descends while moving forward, so the flutes cut the whole way down. A ramp distance of 2 to 3 times the bit diameter is a common starting point (longer for lightweight machines), which is shop advice, so test it on scrap.
2. Raise the plunge rate so the bit doesn't dwell at entry. Dwelling burns and work-hardens the entry point.
3. For V-carving, keep the first pass shallow via the tool's Pass Depth (see the V-carve multi-pass entry) so the fragile tip never takes a full-depth plunge.

Pro tips

• A Spiral ramp is a Profile toolpath option. It ramps down around the whole profile and is not available when lead-ins are used. It is useful when there is no room for a straight ramp.
• The Fluting toolpath has its own ramps at the start and end of each flute.
• Plunge divots inside pockets matter less (the pocket floor gets recut), but they matter most on profile entry points. Use lead-ins on visible edges so the entry mark lands off the final surface.