A step drill bit for stainless steel and hard metals, made from cobalt-enhanced HSS to resist heat and wear. Workshops and serious hobbyists gain confidence when YOKOCUT Cobalt Step Drill Bit reduces bit changes and stays sharp under repeated use. Does the 15-step 4–32mm range and AlTiN coating suit heavy-duty metalwork?
⚡ At a Glance
- • Cutting Quality: Triple-ground cutting edges in M35 5% cobalt HSS deliver clean stepped holes and strong wear resistance
- • Best for: Workshop professionals and serious hobbyists needing multiple hole sizes without frequent bit changes
- • Not ideal for: Fine, single-diameter metalwork or precision woodworking where specialist drill bits are preferable
M35 5% cobalt HSS construction with AlTiN coating and triple-ground edges, supplied in a 15-step 4–32mm format. Designed to cut stainless steel, steel, sheet metal, iron plate, aluminium, ducts, wood, PVC and plastic.
Longer tool life – with M35 5% cobalt HSS construction
M35 HSS contains 5% cobalt and reaches 66–69 HRC, increasing heat and wear resistance; cutting edges are ground three times to maintain sharpness. The high hardness and grind quality reduce edge rounding during steel drilling.
Fewer bit changes and extended service life during heavy metalwork, lowering the effective cost per hole over time.
Versatile hole sizes – with 15-step 4–32mm stepped geometry
Fifteen distinct stepped diameters cover 4mm up to 32mm in one cutter, allowing progressive enlargement without swapping tools. Each step corresponds to common hole sizes used in sheet metal and ductwork.
Quickly drill a range of holes for tasks such as duct installation, panel fittings and bracket mounting without stopping to change bits.
Heat and friction resistance – thanks to AlTiN coating and triple-ground edges
AlTiN coating reduces friction and helps dissipate heat at the cutting face, while triple grinding sharpens the lip and improves chip evacuation. The combined treatments enhance cutter performance under sustained loads.
Smoother cuts when using cutting oil, with reported retention of sharpness after multiple steel holes and stable performance during longer drilling runs.
✨ The 4 Key Reasons for YOKOCUT Cobalt Step Drill Bit
- M35 5% Cobalt HSS – High hardness for prolonged life in stainless steel drilling
- 15-Step 4–32mm Range – Eliminates frequent bit changes across commonly used hole sizes
- AlTiN Coating – Reduces heat and wear for longer cutting sessions
- 3-Flatted Shank – Locks firmly in chuck for stable, wobble-free drilling
📋 Technical Details at a Glance
- Category: Step drill bit
- Material: HSS Cobalt M35
- Cobalt content: 5% Cobalt
- Hardness (HRC): 66–69 HRC
- Coating: AlTiN coating
❓ Frequently Asked Questions
Q: Can the bit cut stainless steel?
A: Yes. The bit is designed specifically for stainless steel and other hard metals, listing stainless steel, steel and iron plate among suitable materials.
Q: What hole sizes are included?
A: Fifteen stepped diameters cover 4mm through to 32mm, allowing sequential enlargement without changing tools.
Q: Will the cutter stay sharp after multiple steel holes?
A: User feedback reports the bit stays sharp after drilling multiple steel holes, supported by the triple-ground cutting edge and high HRC cobalt steel construction.
🏆 Our Verdict
The YOKOCUT Cobalt Step Drill Bit suits workshop professionals and serious hobbyists who need durable, multi-size drilling in metal. M35 5% cobalt HSS, AlTiN coating and triple-ground edges combine to extend life and reduce tool changes. Although a higher upfront cost is noted, the low cost per hole and longer service life deliver strong long-term value.
