Milwaukee Switchblade Selfeed Bit

This is according to a Milwaukee Press Release (available on thomasnet.com):

“Milwaukee Electric Tool Corporation introduces SwitchBlade(TM) selfeed bits, a new solution designed to ensure that contractors maintain a sharp blade.”



Key features include heavy-duty 7/16" quick-change hex shank for ensuring secure chuck grip and blades that are precision-ground for producing clean holes. The selfeed bit is replaceable (comes with second replacable blade) which maintains a sharp blade twice as long as normal (naturally). Material used is investment cast high alloy steel, promising to hold sharp cutting edges longer. Milwaukee also claim that the "newly designed aggressive feed screw provides 12% faster cutting than a standard selfeed bit".

The drill bits come with accessory storage kit, which includes replacement blades and hex wrench for quick replacement.

These bits are targeted for plumbers, electricians and HVAC contractors, and are available in sizes most frequently used by these professionals. The "SwitchBlade selfeed bits are used for drilling multiple holes in all types of wood and for various types of pipe, vent and gas lines and bulk wire routing."

These new drill bits will be available in July of 2008.

Why Do Drill Bits Have Flutes?

The reason for the flutes is that drilling creates waste material, which has to go somewhere. (Its more common trade name is “swarf”). Therefore the flutes are there as the escape path for the swarf. This is why it is recommended that when you drill wholes deeper than about half a centimeter, withdraw the drill now and then to clear the swarf away. This will help to prevent clogging, overheating and various potential resulting damage.

For the same reason, never drill deeper than the drill flutes, because there will be no room for the waste material to escape, and you could damage both the tool and the project.