Cobalt Number Size Drill Bit Set #1-60 - M35 HSS Jobber Drill Kit

In this review the Cobalt Number Size Drill Bit Set #1-60 is evaluated for metalworkers and hobbyists who need a wide range of precise holes in tough materials. The bottom line: this kit's biggest selling point is its complete span of number sizes and M35 cobalt construction, which make it useful when drilling stainless steel, cast iron and other hard metals while still handling wood and plastic. The set is best for users who value size variety and cutting performance over professional-rate lifetime toughness.

Key Features

• 60 Number Sizes: Includes number sizes #1 through #60, providing a continuous range from 0.228in to 0.040in so a single kit covers many drilling needs.
• M35 Cobalt Construction: The M35 cobalt alloy offers harder cutting edges than standard HSS, which improves durability and performance on stainless steel and cast iron.
• 135 Degree Point Tip: The split 135 degree tip helps with self-centering and reduces walk-off, making it easier to start holes accurately on metal.
• Jobber Length Twist Design: Jobber length and spiral flutes clear chips efficiently and let the bits penetrate a variety of materials from soft metals to plastics and wood.
• Storage Case: The indexed storage case keeps bits organized by number size and protects flutes in transit, helping prevent loss and mix-ups.

Who It's For

The kit suits home shop machinists, fabricators and DIYers who frequently switch between precise small diameters and must drill a range of metals, including stainless steel and cast iron. The full #1 to #60 selection removes the need to own multiple partial sets when working on mixed-material jobs.

It is less ideal for heavy production shops that require industrial longevity or carbide tooling for continuous high-volume stainless work; some buyers report bits dull or break under very heavy use, so professionals with high throughput should consider hardened specialty tooling instead.

Pros & Cons

Pros

• Extremely comprehensive size range lets you pick the exact number size without grinding or reaming.
• M35 cobalt composition gives better cutting performance on hardened metals than ordinary HSS.
• 135 degree tip and twist geometry reduce walking and improve hole accuracy for starting holes.
• Indexed case provides neat organization and quick size identification on the job.

Cons

• Some users report edge dulling and occasional breakage during heavy use, so long-term durability can vary under extreme loads.

Specifications

Brand	MACXCOIP
Bit Count	60 pieces (#1-#60)
Size Range	0.228in - 0.040in (5.79mm - 1.02mm)
Material	M35 cobalt high speed steel
Tip Angle	135 degree point
Length	Jobber length twist drills
Storage	Indexed protective storage case

Our Verdict

The Cobalt Number Size Drill Bit Set #1-60 is a practical, value-oriented kit for anyone who needs fine incremental sizes and better-than-average performance on hard metals. It represents solid value for hobbyists and small shops who drill a variety of materials, though those needing industrial-grade longevity under continuous heavy loads may prefer specialized carbide or industrial toolroom bits.

Frequently Asked Questions

Can these drill bits cut stainless steel?
Yes. The M35 cobalt composition and 135 degree point make them suitable for drilling stainless steel and other hardened metals when used with appropriate speed and lubrication.

Are all sizes included from #1 to #60?
Yes. The kit contains number sizes #1 through #60, covering 0.228in down to 0.040in for precise small-diameter work.

How are the bits stored?
The set comes with an indexed storage case that keeps every bit in its labeled slot to protect flutes and simplify selection on the bench.