9ce7951f_vice_by_Logan_Graphic_Products__Cause
[Problem] Over cuts (blade cutting past each corner with visible mark) [Cause] 
Because of excess blade depth the start and stop indicator line on the cutting head is no longer accurate. Using it causes the blade to start its cuts sooner and stop its cut later than needed resulting in cuts that go past the corners. This too is caused by too much blade extending out the bottom of the cutting head.
Mat Cutting Advice by Logan Graphic Products
Cause