Jonathan,
I did take it very easy with that cut. Depth of cut was only 0.5mm, step over was 20% which would be just under 1mm and feed speed was 10mm/sec for that cutter was 10mm/sec. The only cutter I was was not new so I did go slowly with it. The alu also has some hard sections in it so that was why the cutting fluid was generously applied. The starting point was a mistake, I for got to set my dxf to 0,0 in cad and I think cut2d picked that up.
I have had a look at the program file and cant see any G64 codes in it. Youll need to excuse my ignorance in G codes at the moment, I havent got round to learning them yet!!
Some photos are attched of the cut edge. Quality looks good for an old cutter.

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