I am working on a set of skateboard parts today on the Haas VF2.
One of the difficulties I ran into pretty quick on the first part was how long I had to stick out a couple of the endmills I'm using. There is a large bump/cup shape on the top of the part that has a very organic body to it, which requires a slow spiral toolpath with a ball endmill to ensure it all flowed nicely together. Because of this, I had to use a smaller endmill then I usually would to get into all the crevices and would have to have it stick out over an inch to get all the shallow features. Unfortunately, this meant the tool would vibrate while cutting the aluminum and left some weird surface finishes. Thankfully these parts will be tumbled afterward, and that will remove all the marks left by the vibrations but isn't my best work, and I may switch the toolpath up for a morphed spiral to see if I can get a better finish.
There are also two slots at the bottom of the part I needed to mill out on the part which I tried to do on the first operation with a 1/8" endmill and 1.25" tool stick out, but the vibrations were so bad it left a horrible finish.
Since this is a skateboard part, the tolerance doesn't need to be super high, and the looks matter more than accuracy. It still is an exciting challenge to machine out all the small features and getting good finishes in a relatively short period. There are a few small pockets that require a 0.04" endmill to clean up, which requires quite a bit of the machining time.
This first part will consist of three operations, first and second will get the majority complete on the 3-axis mill, then it will be finished up on the 4th-axis to get a couple of small features that I'm not able to reach on the previous setups.