Colin,
I think your cutting parameters are right at the limit of the tool...as long as the tool engagement angle is not increased by going inside corner...as you've found. Having said that, your feedrate is just simply too high for the feature you're trying to cut. So yes, you are pushing too hard.
Unfortunately, with your CAM program, you have to limit your cutting parameters with regards to the feature, and this will leave some time on the table.
We switched from OneCNC to a different package last year because of the ability to have high speed toolpaths AND a feed optimizer. (ANY machine can benefit from these more advanced toolpaths) I heard that OneCNC was planning to add high speed toolpaths in the future...not sure about the feed optimizer/high-feed/adaptive feedrates.
In the meantime, if you're really concerned about your cycle times, you will have to manually edit the program to slow your feedrate for the corners. I suggest a program called NCPlot...they offer a demo before purchasing. Also, you could start conservatively, then listen to the cut while watching the line numbers on the control. Take notes, and increase feed rates where it sounds like the tool can handle more.
Anyhow, with this limitation in mind, I suggest using a two flute endmill rather than a three flute for pocketing operations, until you get to 3/16" or smaller, then I prefer a three flute for tool rigidity. With soft and gummy materials such as aluminum, two flute endmills can accept a higher feed per revolution than three flute endmills. Also, two flute endmills like to plunge MUCH better than three flute tools, which can expedite your pocket entry.
Regards,
Justin  |