Precision HSS Annular Cutter M18 Weldon Shank Magnetic Drill Bits

Product Specification

Precision Magnetic Drill Bits M18 | Professional Weldon Shank Cutters for Multiple Plate Thicknesses

Problem: One Size Does Not Fit All in Steel Fabrication

In complex steel projects, using a "shallow" cutter for deep holes leads to tool jamming, while using a "deep" cutter for thin plates can lead to unnecessary vibration and wasted time. Fabricators often struggle to find a reliable supplier who offers consistent precision across both standard and extended drilling depths, leading to inconsistent hole quality across a single project.

Cause: Chip Evacuation and Structural Rigidity

A 30mm depth cutter is optimized for speed and rigidity on standard plates, but it cannot reach through heavy H-beams. Conversely, a 50mm depth cutter has longer helical flutes; while it handles thick sections, the longer body requires more precise chip management to prevent clogging. Without both options in the toolbox, operators are forced to compromise on efficiency or safety.

Solution: The M18 Dual-Depth Professional Range

We provide a complete 18mm series in both 30mm and 50mm cutting depths. Both are manufactured from premium HSS-M2 with identical CNC-ground tooth geometry. The 30mm version is your "speed king" for standard fabrication, while the 50mm version is your "deep-reach specialist" for heavy-duty structural sections. Both utilize the standard 19.05mm Weldon Shank, ensuring 100% compatibility with your existing magnetic drill fleet.

Technical Parameters.

Application Scenarios: Choosing the Right Tool

• The 18x30mm Specialist: Best for general structural steelwork (bolting M16 fasteners), gusset plates, and standard H-beam flanges. It offers maximum rigidity and is less prone to vibration.

• The 18x50mm Specialist: Essential for heavy-duty shipbuilding, bridge piers, and "stack drilling" (drilling through multiple 10mm-15mm plates at once).

• Cross-Industry Use: Both are widely used in the Energy and Oil & Gas sectors for creating precise clearance holes in structural supports.

Selection Guide: Pro-Tips for the M18 Series

1. Pilot Pin Match: Note that the 50mm series requires a longer pilot pin (103mm) to trigger the slug ejection. Do not mix them up with the 30mm series pins.

2. Coolant Pressure: For the 50mm series, increase internal coolant pressure. The chips have a longer path to travel, and constant lubrication is vital to prevent heat friction.

3. M16 Clearance: Remember that 18mm is the standard "Class 1" clearance for M16 bolts. Having both 30mm and 50mm depths ensures you can handle any M16 bolting task on site.

Professional FAQ

Q: Can I use the 50mm cutter to drill a 10mm plate?

A: Yes, it will work perfectly. However, the 30mm cutter is slightly more rigid and might offer a marginally faster cycle time for very thin materials.

Q: Do these cutters fit my Euroboor or Alfra machine?

A: Absolutely. The 19.05mm (3/4") Weldon shank is a universal industrial standard compatible with all major magnetic drill brands.

Q: Why choose HSS-M2 instead of TCT for the 18mm size?

A: For sizes under 20mm, HSS-M2 offers superior impact resistance and can be re-sharpened, making it more cost-effective for general steel construction than TCT.

Q: Can I stack-drill two 20mm plates with the 50mm cutter?

A: Yes. This is one of the biggest advantages of the 50mm series. It allows you to drill through multiple layers in a single pass, ensuring perfect hole alignment across all plates.

Q: What is the recommended RPM for 18mm HSS cutters?

A: For mild steel, we recommend a speed of approximately 450–600 RPM with constant internal lubrication for optimal tool life.