Thanks all for your help so far. I have made another attempt at approximately 16,000 RPM and raised my X/Y feed rates to 700mm/min. I’m getting chips, as opposed to aluminum dust, but still not able to complete a cut through 1/4″ plate. About half way through, the tool starts chattering and it’s all over. I’m sure it’s just a matter of rigidity, or the lack thereof. My Z-height is currently about 4″ and I already have a 1″ spoil-board under the work piece. I’ve got room to lift it another 3/4″ or so, but that’s all I can do without re-mounting my tool holders to a higher point on the z-axis tubes.
With all of that in mind, I’m going to re-work the machine slightly. Does anyone have experience with the upgraded middle-z setup originally posted by “Camar0” (here)?
I have also been thinking about making the universal mount (here) and this would be the perfect time to add it to the machine. I’m somewhat worried that the universal mount itself will introduce more slop. Can anyone comment on this upgrade?