First to explain why I'm asking.
I wanted to cut out a basic rectangle with rounded corners and some holes from a piece of (about) 1/4" aluminum with an 1/8" end mill, and doing the boarder in three or four passes.
The holes went fine but doing the edges the end mill broke before it finished the first pass, ok slowed down the feed rate and it broke the second end mill during the second pass.
I have the mill spindle set to the highest speed, 2500 rpm by the chart.
So my question is, is that to low of a spindle speed for that small of an end mill?
I ask because I see some mills running at much higher RPMs and seem to cut fine with small end mills.