M35 Cobalt 21-Pc Drill Bits for Steel & Stainless – 135° Split Point, Jobber Length, Indexed Case
XRTOOLS 21-Pc M35 Cobalt HSS Drill Bit Set — Black & Gold, Inch Sizes, Heavy-Duty Metal Index Box
Purpose-built for shops that drill metal every day, the XRTOOLS 21-piece M35 cobalt set pairs hot-hard M35 HSS-Co (~5% Co) with a 135° split-point and fully ground flutes to keep holes straight, chips moving, and cycle times down. The black & gold finish helps manage friction and makes edge wear easy to see, while a steel index box protects and organizes the whole kit.
What makes it different (multi-angle value)
1.Process integrity: Blanks are normalized, CNC flute-ground, and vacuum heat-treated before finish grinding for consistent hardness and runout.
2.Edge that lasts: M35 retains hardness at temperature—ideal for stainless, carbon & alloy steels and cast iron—so you sharpen less and drill more.
3.Fast, clean starts: The 135° split-point self-centers, reduces thrust, and cuts down on walk even on curved or coated surfaces.
4.Real chip control: Fully ground, polished flutes evacuate chips smoothly; margin relief lowers friction on the hole wall for a better finish.
5.Ready for work: Jobber length, round shank fits any 3-jaw chuck (corded, cordless, press). Labeled metal case speeds size selection and inventory.
Applications that pay off
Fabrication & frames: Brackets, channels, angle, base plates.
Electrical/HVAC: Panel work, pilot holes for knockouts, enclosures.
Automotive/MRO: Mounting, upfit holes, fastener prep, stainless trim.
General shop: Fixtures, guards, jigs, and small batch production.
For thick austenitic stainless, use cutting oil, lower RPM, and peck to control heat.
Key specifications
Feature | Detail |
|---|---|
Substrate | M35 HSS-Co (~5% cobalt), fully ground |
Point | 135° split-point, web-thinned (self-centering) |
Flutes | Precision-ground twist, polished for chip flow |
Finish | Black & Gold (steam-treated/oxide + polished lands) |
Length | Jobber |
Shank | Round, 3-jaw chuck compatible |
Sizes (inch) | 21 pcs: 1/16, 5/64, 3/32, 7/64, 1/8, 9/64, 5/32, 11/64, 3/16, 13/64, 7/32, 15/64, 1/4, 17/64, 9/32, 19/64, 5/16, 21/64, 11/32, 23/64, 3/8 |
Case | Heavy-duty metal index box, size callouts, snug wells |
Resharpenable | Yes—maintain split-point geometry |
Recommended cutting practice (quick guide)
1.Mild steel: 15–25 m/min surface speed; steady feed; coolant optional.
2.Stainless (304/316): 8–12 m/min with cutting oil; peck on deep holes.
3.Aluminum/brass: 60–90 m/min; light oil improves finish (optional).
Quality & compliance
1.Runout & concentricity checked 100% on sampled lots.
2.Hardness verified post-treat to M35 spec; edges micro-honed to reduce chipping.
3.Lot traceability on case label; optional EN/RU bilingual labeling for export.
Packaging & OEM options
1.Retail-ready steel index box (sleeved & barcoded); master cartons for distributors.
2.Private label: your logo laser-etched, custom assortments (metric/imperial), custom finish (black oxide or black-&-gold), data sheets with your brand.
FAQ (new set)
Will these replace my titanium-coated HSS set?
Yes—on steel and stainless you’ll see longer life and cleaner holes versus TiN-only HSS.
Impact-driver compatible?
Round shank is for 3-jaw chucks. Ask about our hex-shank cobalt line for impact use.
Can I mix sizes (custom 21-pc map)?
Absolutely—OEM assortments and mixed metric/imperial maps are available.
How often should I resharpen?
When lip wear reaches ~0.5–1.0 mm or chip color stays dark at normal feeds. Keep the split-point geometry.
Get in Touch
Have questions about our products or want to discuss a custom order? Our team is ready to help you.