Chicago-Latrobe
Chicago-Latrobe 42783 M 4-3/8" HSS 135 Deg Jobber Drill Bit pneumatic accessory
A jobber-length drill bit made from high-speed steel with a 135-degree split point for accurate starting
- TypeDrill Bits
- 135-degree split point reduces walking and starts holes accurately
- High-speed steel construction resists wear for longer cutting life
- TiAlN coating lowers friction and heat during drilling
- Jobber length provides standard reach for general-purpose drilling
- Decimal size .2950 matches letter M for precise hole sizing
Chicago-Latrobe 42783 M Drill Bit
The Chicago-Latrobe 42783 M is a jobber length drill bit made from high speed steel. It is designed for general purpose drilling in metal, wood and plastic. The split point geometry allows for accurate starting without a centre punch. This bit suits maintenance technicians and workshop users who need a reliable replacement or addition to their drill index.
TiAlN Coated High Speed Steel Construction
The TiAlN coating increases surface hardness and reduces friction during prolonged drilling cycles. This helps the cutting edges retain sharpness longer than uncoated high speed steel under sustained load. Heat resistance is improved, allowing the bit to run at higher speeds without premature wear. The 135 degree point angle distributes cutting forces evenly across the lips.
.2950 Inch Decimal Equivalent
The critical specification for selecting this bit is its decimal equivalent of .2950 inches, corresponding to letter size M. This exact diameter determines whether the bit matches the required hole size for tapping, clearance or reaming operations. Verify the decimal equivalent against your engineering drawing or tap drill chart before purchase. No other dimension overrides this fit criterion.
Highlights
- 135-degree split point reduces walking and starts holes accurately
- High-speed steel construction resists wear for longer cutting life
- TiAlN coating lowers friction and heat during drilling
- Jobber length provides standard reach for general-purpose drilling
- Decimal size .2950 matches letter M for precise hole sizing
Specifications
| Brand | CHICAGO-LATROBE |
|---|---|
| Type | Drill Bits |
Questions about this item
Will the 135 degree split point on the 42783 drill bit reduce heat buildup during extended drilling sessions?
The 135 degree split point design on the 42783 bit allows for faster penetration with less pressure, which helps minimise heat generation during prolonged use in metal.
What type of drill chuck is required to hold the .2950 inch shank of this jobber bit?
The .2950 inch diameter shank fits standard three-jaw drill chucks that accommodate jobber length bits of this size.
Can the TiAlN coated 42783 bit be used effectively in a vintage hand-crank drill press?
Yes, the 42783 bit works in older hand-crank presses; its split point starts accurately at low speeds, though the TiAlN coating performs best with consistent power feed.
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