Core Bit Extension Rods for Deep Vertical Holes in High-Rise Construction

Mechanical, plumbing, and fire-protection rough-in on high-rise projects often requires holes deeper than a standard core bit barrel can reach in a single pass. Extension rods connect multiple core bit sections, allowing continuous drilling through thick floor slabs and beam structures. Protec Tools extension rods and matching core bits are designed for aligned, vibration-free deep vertical drilling.

Extension Rod Setup

Each extension adds length and potential runout error. Use precision-ground rods with tight tolerance couplings to minimize wobble at depth.

• Single extension: Adds 300–500 mm for standard floor slab thicknesses.
• Multiple extensions: Required for transfer slab and beam drilling — stabilize with guide templates.
• Water feed: Verify center-feed water reaches the cutting face through the full rod stack.

Alignment and Safety

Vertical holes through structural elements demand plumb alignment within engineer tolerance. Use a laser plumb bob or drill rig with built-in level before committing to full depth. Bind-up at depth generates dangerous torque — maintain peck-drill intervals every 100 mm.

Site Checklist

1. Confirm rod and bit thread compatibility before assembly.
2. Torque couplings to manufacturer specification — loose joints cause runout.
3. Inspect rods for bend or wear at coupling faces before each use.
4. Document hole depth and location per structural drawing requirements.

Protec Tools supplies matched core bits and extension rods for construction drilling applications.

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