milling ?utter make sink in hole in steel billet. locksmith work

end mill drill bit metal billet material building drilling equipment industry construction make hole structure mechanic concept stainless alloy steel high speed aluminium carbide titanium dimple measure punch reduces friction production center machine precision metalworking engineering technical milling lubrication deburr sharp press shavings swarf turnings repairing work ñutter sink locksmith ?utter billet work