Cutting Armoured Cable: 5 Expert Tips for a Flawless Finish

   Cutting armoured cable, often known as SWA (Steel Wire Armoured) or AC (Aluminium Conduit) cable, is a common task for electricians and serious DIYers. However, it’s far from simple. A botched job can compromise the cable’s integrity, leading to moisture ingress, reduced mechanical protection, and serious safety hazards. This guide provides a professional, step-by-step approach to ensure you cut armoured cable cleanly, safely, and correctly every time.

 Why a Proper Cut Matters for Armoured Cable

You might think cutting this cable is just about getting through the steel. The real goal is to prepare it for termination without damaging the inner cores or the armour itself. A clean cut ensures the gland grips properly, creating a seal that is weatherproof and maintains earth continuity. A messy cut can leave sharp swarf that pierces insulation or makes threading the gland nearly impossible. Therefore, taking your time here is non-negotiable for a safe, durable installation.

 The Essential Toolkit for the JobWww.adsscable.cn

Using the wrong tools is the biggest mistake we see. Standard wire cutters or junior hacksaws simply won’t cut it (pun intended). You need tools designed for the job.

•  The Right Tools for Cutting:

• Rotary Tool with Cutting Disc: Offers the most control and precision.

• Angle Grinder: Powerful and fast but requires a very steady hand.

• Manual Armoured Cable Cutters: No power needed, great for tight spaces, but require significant grip strength.

• Hacksaw with a Bi-Metal Blade: A last-resort option; difficult to control and often results in an uneven cut.

•  The Right Tools for Preparation:

• Bench Vise: Crucial for securing the cable safely.

• Wire Brush: For cleaning swarf from the armour.

• Safety Gear: Gloves, and crucially, impact-resistant safety goggles.

 Step-by-Step: How to Cut Armoured Cable Safely

Follow this five-step guide for a perfect cut. Rushing is your enemy.

Step 1: Measure and Mark Precisely
Double-check your measurements. Use a permanent marker to draw a clear, straight line around the entire circumference of the cable. This line is your guide.

Step 2: Secure the Cable Firmly
Place the marked section securely in a bench vise. Don’t overtighten and crush the inner conductors, but ensure it cannot move or spin during cutting. This is the key to safety and a straight cut.

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Step 3: Score and Cut Gradually
If using a power tool, start at low speed. Gently score your marked line around the cable to create a guiding groove. Then, make a series of light passes, deepening the cut each time until you penetrate the armour. Never try to cut through in one go.

Step 4: Clean and Deburr Thoroughly
Once cut, you’ll have metal swarf everywhere. Use a wire brush to vigorously clean the end of the cable and the grooves between the armour wires. This sharp debris is a primary cause of short circuits.

Step 5: Install the Gland Immediately
After cleaning, immediately fit the armour gland. This protects the fresh cut from damage and secures the armour wires. Follow the manufacturer’s instructions for your specific gland type.

 Common Cutting Methods: A Quick Comparison

 ⚠ Attention: Critical Mistakes to Avoid

The Institute of Electrical Engineers (IEE) reports that improper termination is a leading cause of faults in industrial installations. Here are the top pitfalls:

• Using a Blunt Tool: This crushes the cable rather than cutting it, splaying the armour and making gland fitting a nightmare.

• Ignoring Safety Gear: Metal shards in the eye are a life-changing injury. Goggles are mandatory, not optional.

• Cutting the Inner Insulation: This is incredibly easy to do if you cut too deep. Always stop at the armour. You can often twist and break the armour after a partial cut to avoid this.

• Leaving Swarf: Failure to clean properly invites shorts. We team once investigated a fault in a 2025 data center upgrade where a tiny strand of armour swarf bridged two terminals, causing a costly outage.

 Beyond the Cut: Terminating the Cable

Cutting is only half the battle. The purpose is to terminate it. After cutting and cleaning, slide the gland components onto the cable in the correct order. Separate the armour wires, fold them back, and secure them with the gland’s clamping ring. Finally, strip and connect the inner conductors to your terminal block or breaker. Interestingly, a good cut makes this entire process smooth and intuitive.

 Your Pre-Termination Checklist

Before you energize the circuit, run through this list:
☑ Cable is securely isolated and dead.
☑ Cut is straight and clean with no crushed sections.
☑ All metal swarf has been removed (visually and by touch).
☑ Armour wires are neatly trimmed and secured under the gland clamp.
☑ The gland nut is tightened correctly, providing a solid mechanical grip and seal.
☑ Inner conductors are undamaged and properly connected.

Frequently Asked Questions (FAQs)

Q1: Can I use bolt cutters to cut armoured cable?
A: It’s not recommended. While bolt cutters can sever the steel armour, they massively crush and distort the end of the cable, making it almost impossible to fit a standard gland properly and compromising its integrity.

Q2: What is the minimum safety gear I should wear?
A: Absolutely non-negotiable: Impact-resistant safety goggles and heavy-duty work gloves. The process creates sharp, hot metal fragments that can cause serious injury.

Q3: How do I cut armoured cable in a tight space where I can’t use a vise?
A: This is challenging. Your best bet is a manual armoured cable cutter. It requires significant hand strength but can generate enough force to cleanly cut the armour without the cable being fully immobilized in a vise.

Q4: Why did my angle grinder disc get damaged while cutting?
A: Armoured cable armour is made from hardened steel. You must use an appropriate abrasive cutting disc designed for metal. A disc for masonry or wood will shatter, creating a severe hazard. Ensure you are using a thin, reinforced cutting disc.

Q5: Is there a special technique for cutting smaller 1.5mm or 2.5mm armoured cable?
A: Smaller diameter cable can be Meirar difficult to secure and is easier to crush. Use a precision tool like a rotary tool (Dremel) with a cutting disc for the most control, and be extra cautious not to cut into the live conductors inside.