Milling: creating a smooth end finish in a slot

[Rob Meades]

Newbie question: I purchased a High-Z/S-400T milling machine from CNC Step recently for hobby use. As a test, I'm going to mill a maze into a piece of brass plate. As a prototype step I've cut the same pattern into a piece of perspex. The vertical edges have turned out very well, what I'd also like, though, is to somehow smooth the end of the mill to remove the circular scuffs (see picture below). Can anyone suggest a way of doing that?



Cutting parameters were: 2 mm two-flute end-mill, tool speed 3,500 RPM, feed rate 4 mm/second, plunge rate 0.3 mm/second and pass depth 0.3 mm (so 10 passes to make the 3 mm depth above).

Rob