Bosch PRO Metal HSS-G Spiral Drill Bit 3.5 x 39 x 70 mm, 5-Piece Set

The Bosch PRO Metal HSS-G spiral drill bit set provides a reliable solution for precision drilling tasks in metal. Engineered for high performance, these 3.5 mm diameter bits are crafted from high-speed steel, ensuring long-lasting durability and resistance to wear during intensive use. The geometry of the bits facilitates efficient chip removal, which helps maintain a clean cutting path and prevents overheating during operation. This set is designed to deliver consistent results in both professional workshops and home improvement projects.

Advantages

These drill bits stand out due to their precision-ground construction, which allows for fast and accurate drilling without the need for center punching in many materials. The high-speed steel material provides excellent heat resistance, ensuring the cutting edge remains sharp even during prolonged use. Furthermore, the optimized flute design ensures that metal shavings are cleared away quickly, reducing the risk of clogging and improving the overall quality of the drilled hole.

Suitable for

• Drilling in alloyed and non-alloyed steel
• Working with cast iron and cast steel
• Processing non-ferrous metals like aluminum or copper
• General metal fabrication and repair tasks

When it may not be suitable

These drill bits are specifically optimized for metalworking and may not provide the best results when used on masonry, concrete, or extremely hard materials like hardened steel or ceramics. Using them on materials outside their intended scope may lead to premature dulling of the cutting edge.

Key specifications

• Diameter: 3.5 mm
• Working length: 39 mm
• Total length: 70 mm
• Material: High-speed steel (HSS-G)
• Quantity: 5 pieces

How to use

To achieve the best results, secure your workpiece firmly to prevent vibration or movement during the drilling process. Insert the drill bit into the chuck of your drill driver or drill press, ensuring it is tightened securely. Apply steady, moderate pressure while maintaining a consistent drilling speed suitable for the metal being processed. It is recommended to use a cutting oil or lubricant to reduce friction and heat, which will extend the lifespan of the drill bits and improve the finish of the hole.

What to consider before purchase

• Verify that your drill chuck is compatible with a 3.5 mm shank diameter.
• Ensure the working length of 39 mm is sufficient for the thickness of your material.
• Check if your project requires a specific coating, as these are standard HSS-G bits.

Usage recommendations

Always wear appropriate eye protection when drilling metal to protect against flying chips. Start with a low speed and increase gradually to maintain control and precision.