Today I got to make another fixture plate and started programming the final operation for the parts I've been working on the past few days.
For the fixture plate, I took a piece of scrap aluminum and faced the top, then drilled the three holes to match the three on the block of the part to locate it. The whole operation took about seven minutes to program and two and a half to run. F
From there, I started working on the 3rd operation for all the parts and had some difficulties at first when trying to clean off the flat surfaces. After looking at some of the other toolpaths, I noticed that the manufacturing extension was now available. My boss bought the whole Fusion360 package when it first came out, and up until this point, it was all locked, and I didn't have access to any of it. Because of this, I was able to use the deep and shallow finishing toolpath to clean up quite a bit of the part.
There was also a small slit in the part that met up with a hole I drilled on the 4th axis, so I had to cut it with a slitting saw and a contour toolpath. I've never used one of these before, so I was a bit cautious and took it slow at ten inches a minute and three times the width in its sidecut.
When I went running the program, I quickly ran into an issue where the bottom of the saw blade would collide with the steel hard-jaws if I let it run as it should. My boss suggested I move the fixture to the edge of the jaws and relocate the work origin on one of the holes using a gauge pin and dial indicator, which is what I needed up doing. From there, I was able to go through the rest of the toolpath without issue until I got to the cutting out sequence.
The way I machined the part was to leave a block of material in the center to locate off of and have a secure fixturing spot in which I could cut all the features. The piece is a pyramid-like shape with a thin band lining the parameter with nothing in the center. The way I would get it off the block was to cut from the underside and cut away at it from the opposite side until it would just fall. It's tough to explain how it works, but the long and short of it is that you cut away small amounts of material and finish it at the same time, taking tiny steps down until it comes loose. For the longest time, I couldn't understand why it wasn't coming loose; I had the tool cut past the bottom of the flap where it should have just fallen off. I finally figured out that the endmill I was using was a 0.06" endmill and not a 1/16" (0.0625"), which made a surprising amount of difference in the rigidity of the part, being held up by just four thou.