Drill bit set for metalwork promising clean, accurate holes in stainless steel and other hard materials. Tradespeople and keen DIYers gain confidence from durable, heat-resistant bits that cope with repeated use. Is the Rennie Tool Company Cobalt Jobber Drill Bit Set the dependable upgrade any workshop needs?
⚡ At a Glance
- • Cutting Quality: Sharp, dimensionally precise edges for fast penetration in hard metals
- • Best for: Tradespeople and DIY enthusiasts tackling stainless steel and tough alloys
- • Not ideal for: Fine woodworking where specialised wood bits are preferred
M35 HSS alloy with 5% cobalt delivers high heat resistance and durability. A 2-flute, DIN338-ground design ensures rapid chip removal and accurate hole geometry.
Fast, accurate hole starts – with a 135° split point
A 135° split point on sizes from 3mm upwards prevents walking by concentrating cutting action at the tip. The geometry reduces the need for a centre punch and improves initial penetration.
For 4mm work the split point allows confident, centred starts even on stainless steel, cutting setup time for workshop and site jobs.
Sustained cutting life under heat – with M35 HSS alloy containing 5% cobalt
M35 HSS is alloyed with 5% cobalt to raise red hardness and resistance to softening at high temperatures. Fully ground-from-solid manufacturing maintains consistent geometry across the set.
Longer edge life means fewer replacements during heavy use, making the set well suited to repetitive stainless steel and hardened metal drilling.
Cleaner holes and rapid chip clearance – thanks to two-flute geometry and DIN338 precision
A two-flute profile is optimised for effective chip evacuation while the DIN338 ground specification ensures dimensional accuracy and straightness. The combination reduces clogging and improves finish.
Results are neater holes with less rework, useful when drilling component parts or working with CNC, pillar, or handheld drills.
✨ The 4 Key Reasons for Rennie Tool Company Cobalt Jobber Drill Bit Set
- M35 HSS with 5% cobalt – Keeps cutting edge longer during extended stainless steel drilling sessions
- 135° split point – Eliminates walking so you can start holes without centre punching
- Two-flute geometry – Speeds chip evacuation for cleaner holes in metalwork
- Plastic storage case included – Keeps ten 4mm bits organised and protected on site
📋 Technical Details at a Glance
- Category: Drill Bit Set
- Brand: Rennie Tool Company
- Material: M35 high-speed steel, 5% cobalt
- Bit Type: Jobber twist drill bits
- Point Angle: 135° split point from 3mm and above
❓ Frequently Asked Questions
Q: Can these drill bits handle stainless steel and other hard metals?
A: Yes, the bits are specifically designed for stainless steel, hardened metals, cast iron and similar tough materials, as stated in the product description.
Q: Will the 4mm bits need a centre punch before drilling?
A: No, sizes from 3mm and above use a 135° split point that prevents walking, so centre punching is generally unnecessary for the 4mm bits.
Q: Can the bits be used in handheld drills and CNC machines?
A: Yes, the set is suitable for pillar drills, handheld electric drills, battery-powered drills and CNC machines according to the product information.
🏆 Our Verdict
The pack suits tradespeople and experienced DIYers who regularly drill stainless steel and other hard metals. Long-life M35 HSS alloy, a 135° split point and two-flute geometry combine for accurate starts, heat resistance and rapid chip removal. Given the durability and workshop utility, the set represents a practical, long-term choice for metalworking tasks.
