Milwaukee 21/64" Thunderbolt Black Oxide Drill Bit (6 PK)

As a craftsman who's always on the lookout for reliable, durable tools that can handle a variety of materials, I recently had the opportunity to test out Milwaukee's 21/64" Thunderbolt Black Oxide Drill Bit set. This set, which includes six bits, quickly became an integral part of my toolkit. The bits are designed with a thicker core for added strength and a 135° split point tip for precise starts, which significantly reduces walking when drilling. Let's break down my experience with these bits and see how they stack up.

Design and Build Quality

One of the first things I noticed was the robust design of the Thunderbolt bits. The black oxide coating not only gives the bits a sleek appearance but also provides a layer of corrosion resistance. This is a significant plus for anyone working in varied environments where moisture and rust are potential concerns.

The 3-Flat Secure-Grip shank is another feature I found beneficial. It ensures a firm hold in the drill chuck, which is critical for maintaining control and accuracy during drilling. The thickness of the core is immediately apparent, and it gives these bits a sturdy feel that instills confidence during use.

Performance on Different Materials

I tested these bits on a range of materials, including metal, wood, and plastic. The 135° split point tip is excellent for starting precise holes without the bit wandering off target. This is particularly useful when working on metal surfaces where accuracy is paramount.

Metal: When drilling through mild steel, the bits performed admirably. They penetrate the material quickly and efficiently, and the black oxide coating helps reduce friction and heat build-up. However, I did notice that they tend to dull somewhat faster than I expected when used intensively on metal. This necessitates more frequent sharpening to maintain performance.

Wood: In wood applications, the bits cut cleanly and efficiently. However, I encountered some issues with chip clearance. The parabolic flute design is supposed to aid in chip removal, but I found myself stopping occasionally to clear out accumulated wood chips. This can be a minor inconvenience, especially when working on deeper holes.

Plastic: Drilling through plastic was smooth and straightforward. The bits sliced through without causing any chipping or cracking, which is often a concern with more brittle plastics.

Durability and Longevity

Durability is a key factor for any drill bit, and the Thunderbolt bits are designed to withstand substantial use. That said, they are not immune to wear and tear. As mentioned, the bits tend to dull faster when used on harder materials like steel. However, with regular maintenance and sharpening, they can provide a long service life.

I did experience one instance where a bit shattered during use. This was an isolated incident, but it's a reminder that no tool is infallible. Nevertheless, the overall build quality and design suggest these bits are built to last under normal operating conditions.

The Case

The set comes with a sturdy, well-designed case that keeps the bits organized and protected. The case feels durable and should hold up well over time, even with frequent use. It's compact enough to fit easily into a tool bag, making it convenient for transport and storage.

Value for Money

Considering the price point, the Milwaukee Thunderbolt drill bits offer good value for money. They fall into a mid-range category, making them accessible for both DIY enthusiasts and professionals. While they may not match the longevity of higher-end titanium or cobalt bits, they outperform many budget options available in the market.

Recommendations

If you're in the market for a versatile set of drill bits that can handle a variety of materials, the Milwaukee 21/64" Thunderbolt Black Oxide Drill Bit set is a solid choice. The features like the thicker core, 135° split point tip, and 3-Flat Secure-Grip shank make these bits reliable and easy to use.

However, if your work primarily involves drilling through hard metals on a daily basis, you might want to consider investing in higher-end options like titanium or cobalt bits. These will offer better edge retention and longer service life under heavy use.

In summary, I would recommend the Milwaukee Thunderbolt drill bits for general-purpose use, especially for those who need a reliable set without breaking the bank. They offer a good balance of performance, durability, and cost, making them a worthy addition to any toolbox.