HarveyTool

Pros: Prevents top surface edge chipping and tear-away.Cons: Less than optimal chip removal when dadoing or plunging. (Choose an up cut spiral bit for standard more efficient milling.)

Helical

Down cut endmills shear in a downward direction causing the uppermost layer of the material to be pressed down against the material just below it. This motion leaves a perfectly clean top surface edge. A concentration of wood chips in the work path will occur. Hose away excess wood chips to prevent bit breakage.