Chicago-Latrobe
Chicago-Latrobe 49220 Screw Machine Drill Bit 5/16 Black Oxide
High-speed steel screw-machine drill bit with a 135-degree split point and black-oxide finish for 5/16 inch holes
- TypeDrill Bits
- 135-degree split point starts on contact without walking
- High-speed steel construction resists wear in metal drilling
- Black oxide finish reduces friction and chip welding
- 5/16 inch diameter suits screw-machine applications
- Right-hand cutting direction matches standard drill chucks
Chicago-Latrobe 49220 Drill Bit
This Chicago-Latrobe 49220 screw machine drill bit is a high-speed steel cutting tool finished in black oxide for corrosion resistance. It suits machinists and maintenance technicians who need a right-hand cutting bit for general-purpose drilling tasks in metal.
5/16 Inch Diameter With 135-Degree Split Point
The critical specification is the 5/16 inch diameter, which has a decimal equivalent of .3125 inches and a 135-degree split point angle. This geometry allows the bit to self-centre on contact and reduces thrust requirements, making it the deciding factor for hole-size accuracy and material suitability.
Straight Shank Fits Standard Chucks
The bit installs directly into any drill chuck that accepts a 5/16 inch shank, requiring no adapters or special tooling. The most common issue is selecting the wrong diameter for the intended hole or applying excessive feed pressure that can damage the split point on harder materials.
Highlights
- 135-degree split point starts on contact without walking
- High-speed steel construction resists wear in metal drilling
- Black oxide finish reduces friction and chip welding
- 5/16 inch diameter suits screw-machine applications
- Right-hand cutting direction matches standard drill chucks
Specifications
| Brand | CHICAGO-LATROBE |
|---|---|
| Type | Drill Bits |
Questions about this item
What does the 135-degree point angle do for drilling?
The 135-degree split point centres itself and reduces walking, so the bit starts cleanly in steel without a pilot hole.
What does the 5/16-inch size mean for my chuck?
The 5/16-inch diameter fits any 3/8-inch or larger drill chuck; it will not fit a 1/4-inch chuck.
What shank style does the 49220 have for mounting?
It has a straight round shank the same 5/16-inch diameter as the flute, designed for standard three-jaw chucks.
Also in this aisle
People compared these
Same shelf, same checkout — eight coins and a 30-minute rate lock.
