How are spindle speeds calculated for a drill bit?
I've seen dozens of charts that highlight the rpm that should be used for specific drill bit types, bit diameter, and material. However, what if my chart doesn't have the particular type of material or bit that I am using? I'd also like to have some intuition to know if the chart looks right or wrong.
Upon some quick research, it appears that the "cutting speed" is what is ultimately needed for a particular material. I assume the cutting speed for each material must be looked up? Is there a standard or "go-to" place to find these? Then, information about the drill bit can be used to determine spindle speed. Again, what if I'm using a big hole saw or circle cutter, and it's not listed? How do I model the bit to use the cutting speed to determine rpm (for a given material of course)?
I'd also like to know to calculate feed speeds for a drill or mill, but there are presumably more variables. It is probably better answered in another question.