Cobalt Drill Bit Set 29-Piece M35 Cobalt Steel - Durable Metal Bits

In this review the CaRoller Cobalt Drill Bit Set 29-piece kit is judged on durability, range and real-world performance; it is aimed at professionals and serious DIYers who need a reliable, all-purpose set for metal, wood and plastic. The single biggest reason to buy is the combination of M35 cobalt construction and a full fractional size range that covers 1/16in to 1/2in, which means fewer trips to the toolbox and confident drilling through hard materials like stainless steel and high-temperature alloys.

Key Features

• M35 cobalt construction: Offers superior wear resistance and keeps edges sharper when drilling high-strength metals compared with basic HSS bits.
• 29-piece size range: Includes a complete set of fractional sizes from 1/16in to 1/2in, removing guesswork and ensuring the right size for most tasks.
• 135-degree split point: Self-centering tip reduces walking and improves accuracy when starting holes in thin sheet or hard surfaces.
• Fully ground twist design: Reduces friction and heat buildup for cooler drilling performance and longer bit life under load.
• Ergonomic cup-type case: Portable round carrying holder with built-in clip keeps bits organized and easy to access on a tool belt or in a bag.

Who It's For

This set is well suited to professional woodworkers, metal fabricators, mechanics and experienced handymen who frequently drill through stainless steel, cast iron, titanium alloys or hard plastics and need a reliable variety of sizes. The hardened M35 alloy and split point design mean it performs best on tougher materials rather than only softwood or occasional household projects.

Casual users who only need a few common sizes for occasional household repairs might find the full 29-piece assortment more than necessary; hobbyists on a tight budget should weigh whether the cobalt construction is worth the premium for infrequent use.

Pros & Cons

Pros

• High-quality M35 cobalt construction gives better wear resistance and cutting edge retention for metal work.
• Comprehensive fractional size selection from 1/16in to 1/2in covers most drilling needs without buying extras.
• Split point and straight shank design improve accuracy and reduce bit walking at startup.
• Convenient portable case with clip keeps bits organized and easy to carry to jobsites.

Cons

• Durability reports are mixed; some users praise long life while others have experienced breakage with heavy use on very hard alloys.
• Some buyers find the case fit or layout less robust than expected, which can make bit retrieval awkward.

Specifications

Brand	CaRoller
Material	M35 cobalt steel with amber coating
Sizes included	1/16in to 1/2in (29 pieces)
Tip geometry	135-degree split point
Shank	Round straight shank
Case type	Cup-type round carrying case with clip

Our Verdict

The CaRoller 29-piece M35 cobalt set is a practical, good-value option for professionals and serious DIYers who need reliable performance on metal and hard plastics; its full fractional range and split point design make it especially useful for jobs that demand precision. While a few users note case fit issues and variable longevity under extreme use, the set delivers strong cutting performance and convenience for most workshop and jobsite needs.

Frequently Asked Questions

Can these bits drill stainless steel?
Yes. The M35 cobalt composition and split point tip are designed to cut stainless steel and other hard alloys effectively.

Are the bits stored in a durable case?
The set ships in a cup-type round carrying case with a clip for portability; case quality has mixed feedback, so handle the case carefully.

What size range is included?
The kit includes fractional sizes from 1/16in through 1/2in, a comprehensive set for general workshop needs.