On 2015 here
Is there anyway to avoid this situation or do I have to use 2 features to get the chamfers equal off the common face?
Adding an extra (unwanted) edge forces it
Not a very simple reason behind this, and the program is making its own assumptions on the start and end of each side of your part. This assumption is not apparent in the model. SOLIDWORKS has stated that the workaround for this type of problem is to apply each chamfer individually reversing the distance to make them look the same.
I feared as much, but maybe hoped there was a way. It would be nice if we could 'flip' D1 & D2 per edge selected.
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