Cleveland C15900 Cobalt Jobber Drill Bit No 43 135 Deg

Product Description

The CLEVELAND C15900 is a cobalt jobber length drill bit designed for drilling into superalloys, hardened steels, and other difficult-to-machine materials. Built from M42 cobalt high-speed steel with an oxide coating, this heavy-duty bit delivers extended tool life under high heat and cutting stress. It carries a No. 43 wire size designation, corresponding to a 0.0890-inch diameter, and features a 135-degree split point that reduces thrust force and eliminates the need for a center punch. The fast spiral flute design promotes chip evacuation, making it well suited for demanding production and maintenance drilling tasks performed by machinists, tool-and-die tradespeople, and industrial maintenance technicians.

This bit is intended for right-hand cutting in metals where standard high-speed steel tooling falls short. Typical applications include drilling superalloys, stainless steels, and heat-treated materials in aerospace, industrial maintenance, and precision fabrication environments. The straight-cylindrical shank fits standard 3-jaw drill chucks on both benchtop drill presses and handheld power drills. The Series 3780 designation places this bit within a heavy-duty wire-size family intended for close-tolerance work, with a diameter tolerance of -0.0005 to 0.0000 inches ensuring consistent hole sizing. This is a single-piece package with a minimum order quantity of 10 units.

Key Features

• M42 cobalt high-speed steel construction for heat resistance in tough-metal drilling
• 135-degree split point reduces walking and cutting thrust without a center punch
• Oxide coating provides lubricity and mild corrosion resistance during storage and use
• Fast spiral flute geometry promotes efficient chip removal in deep holes
• Web-thinned, tapered web design reduces cutting resistance at the drill tip
• Meets ASME B94.11M standard for jobber length drill bits

Compatibility

Designed as an OEM-style replacement or direct-use jobber length drill bit for applications requiring a No. 43 wire size (0.0890 inch) hole in superalloys and hard metals, conforming to ASME B94.11M and NAS specification requirements.

Installation Notes

This drill bit is installed and operated by machinists or maintenance technicians using a standard drill chuck sized for a 0.0890-inch straight shank. Before use, ensure the workpiece is securely clamped and the drill press or power tool is powered off during bit changes. Cutting fluid or coolant is recommended when drilling superalloys to manage heat buildup, even though this bit does not support through-coolant delivery. Inspect the split point for wear or chipping before each use, as a damaged point will reduce hole accuracy and increase thrust load on the tool.