I've never seen any tear out using a Freund 1/2" diameter straight bit with two carbide flutes. Some woods may be more prone to this but it hasn't happened with West African ebony, Macassar ebony, EIR, maple or the junk fir that I used to test the unit when it was first completed. I move up and down the board lengthwise using quite a few passes, probably a dozen or more, and always radius before cutting the fret slots to avoid the possibility of chipping the slot edges. I don't know how much of a risk this is but my process of cutting the slots doesn't care if the board is flat or radiused so I do the slots last so there's no risk at all.