Cool - that gives me a target for now in terms of tool life from where I am now.

I'm certainly expecting the better compressor to help, as I'll not have slots full of cut chips - although they'll all be stuck in what's left of my hair I expect ;-)

I'll buy some serated edge cutters to play with - they are often called rippers?

I've shied away from 3 flute cutters due to the previous frustrations and lack of feed-rate I could get, but will have a go again now my machine is a lot smoother than it was due to Christmas hols maintenance and the new controller board, which I should have up and running tomorrow.

Luckily the parts I'm cutting for a customer can be left at the rough stage, as they are for a sub-frame to chassis mount and hence buried in the bowels of an engine bay away from public view. He is well happy with the 2 I have shipped already (especially as I can sell them cheaper than the OEM) :-) even if I need to charge a cutter for each part, which with extended tool life over what I have currently I shouldn't have to do. Of course there are many parts which are not so hidden I need the finishing pass on......

BTW - is that tool life using "normal" toolpaths or iMachining/HSM? There are some stunning youtube vids of the latter in steels albeit on what must be very rigid moving bed mills rather than the gantry type and they are claim 70%+ better tool life - shame the continental company that makes the software is not more Google/Trimble rather than Autodesk in terms of price point ;)