Best strategy for sheet aluminium holes and cutouts

New to the world of cnc having recently got my 6040 up and running (0.8W spindle) I'm on the hunt for a plan of action for cutting some aluminium (1.5mm & 3mm thickness)

I'm thinking of buying some carbide TiAlN coated bits as I'm hoping to run it without flood but with an air compressor blowing air direct and a shopvac to collect the chips.* So I've heard that TiAlN coating would be best for that.

I'm looking at some cobra carbide bits from eBay.* Have people used/heard of these before? Recommended?
*http://m.ebay.co.uk/itm/2mm-Carbide-...222?nav=SEARCH

For the actually toolpaths, I'm using HSMexpress in Solidworks and am thinking that for general front panels (3.5mm holes.. maybe larger ones for pots and things 11mm or so.. and the outside cuts of the panel too..)

Is the right thing to do, choose 2d contours in HSMexpress and use a 2mm bit to cut everything? Or is drilling more recommended?* I suppose if possible I'd prefer less tool changes rather than actually speed..*

Try the single flute carbide bits, they work brilliantly on aluminium with air for cooling and chip removal, I've had no issues with plain carbide.
I use 2D contour profiling for a lot of parts, holes too unless it would involve many passes to achieve the hole diameter with the loaded tool.

- Nick

Thanks for the advice.. I was looking for some single cutters too but couldn't find any TiAlN coated ones.. perhaps it doesn't matter so much for single flutes?

I'll pick up some 2mm single flutes then...
Perhaps these:
http://www.cutwel.co.uk/milling/mill...l-e5e47-series

Or Europa Tools http://pages.ebay.com/link/?nav=item...834460&alt=web

Quote:

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Originally Posted by d4cnc

Is the right thing to do, choose 2d contours in HSMexpress and use a 2mm bit to cut everything? Or is drilling more recommended?* I suppose if possible I'd prefer less tool changes rather than actually speed..*

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Use the largest tool you can get away with. If not too many holes then you can use the end mill and either pocket the holes or use peck drilling cycle.
If lots of holes then using a drill will be quicker.

Thanks for advice.. is there a general rule of thumb for what diameter cutter for pocketing a hole.. obviously a 3.5mm cutter in a 3.5mm hole would just be plunging and wouldn't be able to spiral in..
Whereas a smaller bit can spiral in better.

Or is straight down plunging not too much of a problem in 3mm thick aluminium with a single flute cutter? So a 3mm cutter in a 3.5mm hole would be fine to pocket.

Have a look at these http://www.sorotec.de/shop/Cutting-Tools/END-MILLS/

Quote:

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Originally Posted by d4cnc

Thanks for advice.. is there a general rule of thumb for what diameter cutter for pocketing a hole.. obviously a 3.5mm cutter in a 3.5mm hole would just be plunging and wouldn't be able to spiral in..
Whereas a smaller bit can spiral in better.

Or is straight down plunging not too much of a problem in 3mm thick aluminium with a single flute cutter? So a 3mm cutter in a 3.5mm hole would be fine to pocket.

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Well you'd normaly use tool just little smaller than hole if spirling down. So in this case 3mm tool would work well. But if just 1 or 2 holes then using same size tool and peck drilling cycle with small peck amount is quicker.