My second attempt at making the Impeller wasn't as successful as the first.
I wanted to cut back on machining time and reduce the file size of the g-code, so I changed some of the settings. I raised the fine stepdown to 0.025" from the previous 0.008". I also increased the overall size of the Impeller to prevent parts from getting too small. I did keep the finishing passes the same as they were in the previous version.
I ran into an issue pretty quick, the stock I was using was a bit larger than the previous time I machined the Impeller, and my tool reach wasn't quite long enough to machine down to the center of the part. I was able to fix this by using a few facing toolpaths on the corners of the stock, which gave me another 1/8" reach.
I was having some issues with the post-process trying to obtain the g-code, it would fail as soon as I tried to export it. I can't for the life of me figure out why. I played around with which toolpaths I exported and found that certain ones don't work together in the same file, I'm very lost as to why it's doing this. The workaround I found was to select as many toolpaths at once and do them one at a time, time-consuming, but it works.
I ran through five of the seven roughing operations and must have accidentally set the sixth toolpath to have no stock to leave, which caused one of the fins to snap and left too small of a peg to stand on, and so I couldn't do any of the finishing passes. Since the part was pretty much useless at this point, I decided to try out one of the five-axis toolpaths. Namely, the swarf tool, I programmed it to finish the underside of the part and cut it from the base. The underside of the Impeller had a very slight dome-like incline, and the swarf worked out very well (see the last image).
