Skill: Drilling Accurately Through Piers, Walls, and Posts
Skill level: 2
Gate Mechanics
Learning Objective
Learn how to drill clean, accurate cable holes through walls, piers, and posts, using correct tools, technique, and preparation. Understand how to avoid damage, mess, misalignment, and long-term issues like water ingress.
1. Overview
Whether you’re fitting an intercom, keypad, photobeam or push button, cable access holes need to be drilled cleanly and accurately. Poor drilling leads to blown plaster, misaligned holes, unsightly finishes, damaged tools, or worse — water tracking into indoor areas or electronics.
2. Tools & Materials Required
SDS drill (corded for heavy work, cordless for light/finishing)
Sharp SDS masonry bits (standard and long, straight, deep-fluted)
Pilot bit (for thick/awkward materials)
Dust sheets
Hoover or dustpan and brush
PPE: safety glasses, hearing protection, dust mask, gloves
Tape measure, level, and marker pen
3. Before You Start
Check exact entry and exit points before drilling.
Mark hole positions with tape measure and level.
Confirm alignment with a colleague if drilling a long run.
Decide drilling direction: always inside → outside to protect plaster/render.
Plan for water run-off: hole must slope slightly downward to outside.
Confirm you are not drilling into existing cables.
4. Procedure
a. Plan Hole Position
Confirm where cable will enter and exit.
Avoid locations where cables will bend sharply or be exposed.
b. Select Drill & Bit
Use sharp SDS masonry bit of correct length.
Inspect long bits for bends or clogging.
For heavy/thick work, use 230V drill.
c. Drill Technique
Start with a smaller pilot hole if drilling through dense walls.
Let the drill do the work — don’t force feed.
Withdraw bit regularly during drilling to clear dust.
Watch for overheating — swap drills if needed.
Get a buddy to help guide your hole angle.
Holes in the ground can be difficult to keep the drill flutes clear, use an air blower to help blow dust out of the hole and away from you.
d. Maintain Clean Finish
If indoors:
Lay dust sheets before starting.
Hoover or brush as you go, not just at the end.
Keep surrounding area clean to reassure customer.
5. Best Practices
Always drill slightly downward toward outside to channel water away from your delecate electronics.
Confirm drill angle with colleague if unsure.
Keep tools sharp and in good condition.
Protect indoor spaces with dust control.
Leave hole neat and aligned with planned cable run.
6. Common Mistakes to Avoid
Drilling from outside → inside (causes blown plaster/render).
Using blunt or cheap bits that wander or jam.
Forgetting to check where cable will bend or exit.
Leaving flat or upward holes that allow water ingress.
Overheating drill motors or brushes.
Leaving dust/mess indoors.
7. Safety Information
Safe drilling prevents structural damage, tool injury, and environmental hazards (dust, noise, debris). Always follow:
SSOW – Drilling & Use of Power Tools
RAMS – Work at Height & Manual Handling (if drilling ladders/scaffold)
SSOW – Electrical Safety (Before Penetrating Walls)
RAMS – Control of Dust & Housekeeping
SSOW – Use of PPE (Eye, Hearing, and Respiratory Protection)
