13-Pc M35 Cobalt Drill Bit Kit — Precision-Ground, 135° Split
Point, Auto Repair / Stainless / Metal
Designed for real shop workloads, this 13-piece M35 cobalt HSS (≈5%
Co) kit combines a 135° split-point with precision-ground flutes to
start fast, drill true, and last longer in stainless, carbon &
alloy steels, and cast iron. Jobber-length, round-shank bits fit
any 3-jaw chuck (corded, cordless, drill press). A compact metal
index case keeps sizes organized for grab-and-go efficiency in the
bay or on the road.
Why technicians choose it (merged highlights)
Built for tough metals: M35 cobalt maintains hot-hardness in
304/316 stainless, carbon & alloy steels; fewer change-outs,
cleaner holes.
Fast, clean starts: 135° split point is self-centering, resists
walking on curved/painted panels, and lowers thrust at
breakthrough.
Run true, evacuate chips: Precision-ground flutes improve
concentricity and chip flow for rounder holes and better finishes.
Shop-friendly set map: 13 essential inch sizes cover common
pilot/clearance/tap-drill prep used across brakes, body &
under-hood jobs.
Ready for daily use: Jobber length, round shank, and a labeled
steel index box speed selection, storage, and inventory.
High-Intent Applications (search-optimized)
Drill out broken studs/bolts, exhaust manifold & bracket holes,
frame/chassis work
Stainless steel drilling, sheet-metal & panel repair, and tap-drill
preparation
Automotive MRO & fabrication · HVAC/Electrical panels · Mounting
holes & accessory installs
Product Specifications
| Feature | Details |
|---|
| Material | M35 Cobalt HSS (~5% Co) |
| Tip Geometry | 135° split point, web-thinned (self-centering, low thrust) |
| Flutes | Precision-ground twist flutes, polished for chip evacuation |
| Length Type | Jobber (ANSI / DIN 338 equivalent) |
| Shank | Round, 3-jaw chuck compatible |
| Finish | Bright ground (options: Black & Gold, Black Oxide) |
| Recommended Materials | Stainless 304/316, carbon & alloy steel, cast iron, aluminum/brass |
| Storage | Metal index case, size-stamped wells |
| Resharpenable | Yes — maintain split-point geometry |
Inch Size Map with Overall Length (OAL) & Flute Length (FL)
| Size (in) | OAL (in) | FL (in) |
|---|
| 1/16 | 1.875 | 0.875 |
| 5/64 | 2.000 | 1.000 |
| 3/32 | 2.250 | 1.125 |
| 7/64 | 2.375 | 1.250 |
| 1/8 | 2.750 | 1.625 |
| 9/64 | 2.875 | 1.750 |
| 5/32 | 3.000 | 2.000 |
| 11/64 | 3.125 | 2.125 |
| 3/16 | 3.500 | 2.375 |
| 13/64 | 3.625 | 2.500 |
| 7/32 | 3.750 | 2.625 |
| 15/64 | 3.875 | 2.750 |
| 1/4 | 4.000 | 2.750 |
Speed & Feed Quick Guide (rule-of-thumb)
| Material | Surface Speed (SFM) | Notes |
|---|
| Stainless 304/316 | 25–40 | Cutting oil; peck on deep holes |
| Carbon/Alloy Steel | 40–70 | Oil extends life |
| Cast Iron | 50–80 | Dry or minimal oil; avoid rubbing |
| Aluminum/Brass | 150–250 | Light oil optional for finish |
Packaging & OEM (wholesale-ready)
Retail-ready metal index case (sleeved & barcoded); master cartons
for distributors
Private label/OEM: custom assortments (metric/imperial), finish
options, laser-etched logo, EN/RU bilingual labels & spec sheets
FAQ
Will these drill stainless reliably?
Yes—M35 cobalt + 135° split point are engineered for stainless. Use
lower RPM, cutting oil, and peck cycles.
Impact-driver compatible?
Round shank bits are for 3-jaw chucks. Hex-shank cobalt variants
available on request.
Can I get tap-drill or metric-specific maps?
Absolutely—OEM assortments tailored to common automotive tap sizes
or metric ranges are available.
Can they be resharpened?
Yes. Regrind while keeping the split-point geometry; M35 grinds
cleanly and holds an edge.
