I am currently running 2017 SP 2.0, but I believe I have dealt with this issue since 2015.
I have an assembly with a revolved cut at the assembly level.
In this example (screenshot), I am attempting to cope all of the fittings that extend into the shell of a tank.
The green sketch outline is the selected region; however, the preview for the cut (yellow outline) appears to be 1/10th scale for some unknown reason.
After confirming the cut nothing gets cut. Even if I select an object that lies within the 1/10th scale preview, no cuts occur.
I have encountered this many times with many different assemblies.
I am hoping it is just a setting. The only odd thing is, sometimes within the same model the error will suddenly not be present, but then reappear when I try to edit the feature.
Any help would be very much appreciated.