I just ran my first post from Fusion 360 to the centroid M400. This was a live 4th axis test part that was supposed to machine three pockets all 120deg apart from each other. The behavior of the mill was not quite what I was hoping for as the mill table was stuttering whenever a somewhat tight radius would need to be performed. The other part that was even more bizzare was that the pockets did not turn out right either. Every one was different and I used a pattern feature in Fusion to make those pockets, so they should all be the exact same. Whats just as odd is that I ran the part again and the result was different than the first time around ... I am stumped. I don't know how that is even possible because its literally the exact same program.
I put a video on my little channel with the 4th axis running so others can see what it looks like:
. I am running a Fanuc post processor that uses the G93 inverse time command for this.
Notice how the lower wall is not straight, but looks like it was straight about a third of the way into the adaptive clearing tool path? I have no answer for this. I notice if I slow down the feed rate, then the stuttering of the table seems to lessen. Also, the 4th axis can be seen as stuttering as well in its rotation.