Quote Originally Posted by routercnc View Post

As a strategy I think I would:
Spot all the holes (leave finishing for the drill press)
Pocket out all the internal holes and slots (i.e. not an internal profile)
Rough profile the exterior with 6 or 8mm carbide, leaving 0.1mm
Finish profile the exterior with 6 or 8mm carbide in one full depth pass (but still use same tabs as when roughing)
Switch to 2mm cutter and profile the outside again to get the detail then profile the inside of the pockets
Cut away the tabs and tidy up the edges by hand
Thanks for that, interesting stuff, my response...

I really don't want to drill the final holes, IMHO, spiralling down should work ok, will need to test it.

Pocketing out the waste - brilliant point, probably never have thought of that one;)

Rough profile exterior - makes sense but favour a 6mm rather than going bigger.

Finish profile exterior with big cutter - if its only got 0.1mm to go, I'm not sure of the point, a 2mm solid carbide should handle that in one pass AFIK - test again.

The smaller internal shape/pocket would need a smaller roughing cutter, probably 4mm, why not go to finish on the same tool?

Tabs are the same in Sheetcam, bottom upwards. So if i have an aluminium bed, I would not want to request a 6mm cut on a 5mm sheet, I was thinking of using a sheet of stiff card or some-such between, I use a lot of 0.4mm hard card at work and that would likely work well, cut would then go to work plus 0.2mm.

I'm generally against babying cutters, on the Bridgeport I find they are happier when taking a proper cut, within the abilities of the machine, but not tickling the metal, especially with carbide which has a larger edge radius than HSS and needs to 'cut' the metal.

Some good points though, noted, thanks