GERMAN QUALITY
| Type | Drill bit diameter | Art.-No | Set of |
|---|---|---|---|
| 1/2 '' shank HSS / CO5 drill bits | 9/16''-13/16''-5/8''-7/8''-11/16''-15/16''-3/4''-1'' | 35-0002 | 8 piece |
Under normal usage, swarf is carried up and away from the tip of the drill bit by the fluting of the drill bit. The cutting edges produce more chips which continue the movement of the chips outwards from the hole. This is successful until the chips pack too tightly, either because of deeper than normal holes or insufficient backing off (removing the drill slightly or totally from the hole while drilling). Cutting fluid like the METAFLUX 70-03 is recommended to ease this problem and to prolong the tool’s life by cooling and lubricating the tip and chip flow. Coolant may be introduced via holes through the drill shank, which is common when using a gun drill. When cutting aluminum in particular, cutting fluid helps ensure a smooth and accurate hole while preventing the metal from grabbing the drill bit in the process of drilling the hole. When drilling brass, and other soft metals that can grab the drill bit and causes “chatter”, a face of approx. 1-2 millimeters can be ground on the cutting edge to create an obtuse angle of 91 to 93 degrees. This prevents “chatter” during which the drill tears rather than cuts the metal. However, with that shape of bit cutting edge, the drill is pushing the metal away, rather than grabbing the metal. This creates high friction and a very hot swarf.
