Timo, you should have watched the simulation more closely it shows the crash as the tool plunges straight down in red
I don't tend to use pocket that much so below is what I came up with. The reason I don't us epocket that much is you can end up with some large tool engagement, even your setup 1 has that 2mm tool cutting full width and 2,5mm beep which is quite a loading, the adaptive will keep tool engagement down.
-Do the spot drilling as you have first as the 3mm spot drill won't work on that internal corner location if done later.
-Drill holes as you have
- Ream holes as you have
- Do a 3D adaptive with the 4mm dia tool selecting the bottom of the recess as the geometry and set "tool ctr within boundry" as this will ensur eit does not enter from outside the area, leave 0.3 radial and axial
- Do a 3D adaptive with the 2mm tool, same geometry and same stock to leave. But click rest machining and tick "from previous" that way it only machines what the previous cutter could not get at in the corners and where the space is too narrow.
- 3D Horizontal with same 0.3 radial but zero axial stock to leave which will finish the bottom of the recess
=2D contour with 2 roughing passes and one finish pass all of 0.1mm as it's quite a small 2mm dia tool to finish sides of recess
File in my
dropbox to download and see what I did