Originally Posted by
Wes Grass
Forgot, slotting with a 4 flute puts a flute on centerline, which is trying to deflect ... 'things' ... while the trailing flute is generating one of the walls.
A climb cut might need a finish pass to get the dimension and finish you want, depending on material, thickness ... and the rigidity of the machine.
A 2 flute ramps its way in and out of the cut, with less deflection... usually.
Tools last longer as well, on finish passes ... the flute gets a good bite into the material, instead of 'rubbing itself to death' from the progressive entrance with a conventional cut.
Disclaimer: I'm mainly a 'metal dude'.