Parabolic Flute Jobbers Length Drill High Speed Steel and Cobalt Fractional
Parabolic drills feature a unique flute design that greatly enhances chip flow, coolant flow to the drill point and heat dissipation. Recommended for Deep Hole drilling greater then three diameters deep without the need to reduce rate or withdraw the drill to clear chips, {Known as pecking}. Constant heavy feed rate is recommended.
Parabolic drills have a much different flute design with special web thinning, helix angles and Land Width than standard Jobbers Drills. The flute design with a reinforced web increases drill strength and rigidity providing closer tolerance holes and higher speeds and feeds. Split Point drills = Self centering point eliminates "walking" and reduce thrust requiredTanged shank = Allows for use with ASA split sleeve drivers
Bright finish = polished flutes enhances chip evacuation especially for aluminum{s} and other non-ferrous materialsBlack oxide Surface treatment = increases wear resistance,reduces galling and chip welding, increases drill lubrication retention
Tin/Ticn/Tialn coatings = increases drill surface hardness, wear resistance, heat resistance, increases chip flow and resists chip welding. Enhanced hole quality at higher speeds and feeds.All items are new in original manufacturer's packaging {unless otherwise noted}.
They are limited to quantities available.These items are from manufacturer's overstocks, distributors who have changed products lines and manufacturer's who have had print changes and no longer have a particular job in house where items where used.
Visuals are actual item{s}Found this independent article on-line from CNC Cookbook - Parabolics are quite a bit more expensive than the average jobber length twist drills, but for deep holes, they’re darned well worth it. They may even be worth it in shallower depths {Not Sheet Metal} just because of the increased feed rates they can bring. the parabolic flute moved the chips further up the helix due to its faster spiral. Parabolic drills often have other geometry advantages including more room in the flute for more chips and a wider web on the tip for greater durability.