Hey Guys, I now made several fingerjoints, the problem is: The corners are not straight, they are always a bit above 90° so that they don’t match exactly. You can see some pictures here: MPCNC Primo Schneewittchen - Oldenburg, Germany - #21 by Tokoloshe
I know that the bindings are not sanded down, but in the top view you can see that there is a lot of air, like half a mm above and below the finger. Could it be that the machine is too fast so it has got too much momentum? I cut the pieces at 1200mm/min with 2.2mm depth.
The wood being thicker than the pockets are deep is not a problem either (it is a problem, but I know why. The wood was sold as 6mm thick, it is factually 6.4mm thick, wich I didn’t know when making the model.).
Any tips are appreciated, I love fingerjoints and want them to be beautiful. 
(I know, there will always be the “round” corners, even with “Freifräsen” in Estlcam.
Is your z axis perpendicular to the xy plane?
Looks like something a finishing pass could help with, if you’re not already.
Argh, my picture is not good. the ones that are not straight are smaller than the others, not bigger. I drew it wrong. I am sorry for the confusion. So no, a finishing pass would not help. I’ll try it a little slower tomorrow or in the next few days and will tell you how that went.
If you switch between conventional/climb cuts, it might cut outside instead of inside. But a finishing pass may help anyway, because the first cut is farther away.
Thought the same - in static mode, it will probably be. I saw such deviations when my old steel/PU belts approached their lifetime limits and at the same time I found out that my burly core was anything but solid. Plus some play in the bearings settings. Primo parts are ~ 70% printed now.
In other words: How does your (Philipp) router mount react to an enhanced earthquake/meteor impact test ™?