I'm running a job machining badges on my Emach cnc router and am breaking cutters frequently. Wasn't too bad on the original stock that I had -duraluminium I think -but now I'm using 5251H22 cutter life is dire.
Details are:
Cutting tool speed 21000 rpm
Cutter travel speed .25m/ min
Cutter pas depth .3mm
Tool = 2mm single flute carbide cutter from ITC Ltd
Coolant = ITC coolant via mister

I can't increase the cutter size due to the small radius on some of the letters. Am I better using a softer grade of aluminium or will I then get chip clogging?

Any thoughts where I'm going wrong? It's getting a bit pricey at £20+ per cutter