SPOTTINGDRILLRECOMMENDATIONS FOR SOLID CARBIDE AND QWIK TWIST DRILLS >
BEST Spotting drill angle is greater than the drill point angle. First contact is at the drill point.
ՕBest drill centering possibility.
Drill loading increases with penetration. >
ACCEPT ABLE Spotting drill angle is the same as the drill point angle. ՕTool loading proble m s can occur due to i mm ediate full engage m ent.Chatter m ay be a proble m .ՕReduced feed at entry reco >
mm ended.Good drill centering. >
NOT RECOMMENDED WITH CARBIDE Spotting drill angle is less than the drill point angle. ՕPoint contact along cutting lips or corner - drill point should contact spotted hole first..Chipping likely in these areas. >