Do you want to cut fast or do you want to cut smooth? Generally, bit selection is based on whether speed or accuracy is the most important consideration at a specific stage of processing. For example, with straight cuts choose an end mill bit for speed. If you are carving, a ball nose bit will give you the best detail.
Feeds and speed will vary depending on the horsepower of your spindle, whether panels are held by clamps or vacuum, the stability of your CNC machine, and the condition of your collet, among other factors.
Plan to start cutting your material at a lower rate and gradually increase the speed and feed until the quality of your finish becomes unacceptable.
Getting comfortable with trial and error is the mark of a CNC expert.
Chip Load is a calculation which measures the amount of material removed by each cutting edge during a CNC cut. The feed rate is how fast material moves through the machine. Here’s the formula for calculating Chip Load:
Chip Load = Feed Rate (inches per minute)/(RPM x # flutes)
Chip Load is the size of chips created by a bit when making a cut. Chips too large might break a bit while chips too small turn your waste to powder and dull the bit.