A pair of 2flute 6mm cutters arrived. Very cheap and came in 4 days from UK not HongKong. http://www.ebay.co.uk/itm/190984562714 price was only £1.69 last week ! I've got some more expensive ones as well coming from china, comparisons will come in due course.

So I disconnected Z, and that allows me to drive around in X and Y.

Feed 1200mm/min. 6000RPM.

First I did full width passes along the top at about 1mm doc > all fine.

Then I sidemilled the endface with doc 3mm stepover about 1.4mm. Fine conventional but when I tried to climb mill on the way back I got a loud vibration.

That made me panic and I hit a key (aiming for reverse!) and instead took a cut at full width 9mm doc. That too made a noise but nothing broke.

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I'm pretty pleased. Acetal is the easiest plastic to work with, and I'm all for making life easy. These feeds and speeds are plenty for the small pieces I have planned.

I'll probably go back to 16 microsteps giving a max feed around 2300 as I don't think I'll be needing 4700 mm/min.


Hoping my replacement drivers arrive soon so I can do some CNC.