How to Pick a Tubular Lock: A Detailed Look Into This Unique Lock Mechanism

Introduction

Locks have safeguarded our property and privacy for centuries, evolving through countless designs and mechanisms. Among the many lock types in use today, the tubular lock—also known as the circular or radial pin tumbler lock—stands out for its unique structure and widespread use in everyday machines. You’ve probably seen it securing vending machines, ATMs, bicycle locks, gaming machines, and laundromat equipment. Its round keyway and characteristic circular key design make it visually distinctive and mechanically intriguing.

But what happens when you find yourself locked out of your own property because you’ve misplaced the key? Or when a vending machine technician needs to gain access to service a jammed machine? Understanding how tubular locks work—and how they can be picked responsibly for legitimate purposes—is both a fascinating study in mechanical design and a practical skill for locksmiths and security professionals.

This article provides a detailed, responsible guide to understanding the tubular lock mechanism, explains how a tubular lock pick tool works, and outlines the step-by-step process for picking one—always with an emphasis on legal and ethical use.

What Exactly Is a Tubular Lock?

At its core, the tubular lock is a specialized version of the standard pin tumbler lock, but with a major twist—literally. Instead of arranging the pins in a straight line like in traditional Yale-style locks, tubular locks arrange their pins in a circle.

This radial arrangement provides certain advantages:

Increased picking resistance: The circular design can make picking attempts more challenging than linear pin tumbler locks, especially for amateurs.

Compact design: The lock cylinder is smaller, making it ideal for vending machines and other compact applications.

Unique key shape: The tubular key is a hollow cylinder with precisely milled notches on its edge that match the positions and depths of the lock’s pins.

When you insert a tubular key into the lock, the notches push the pins back to their correct positions, aligning them at the shear line, so the lock plug can rotate freely. If any pin is misaligned—even slightly—the plug remains locked.

The Inner Workings: Behind the Tubular Mechanism

To truly appreciate the art of tubular lock picking, it helps to look inside the mechanism. Let’s break it down:

1. The Plug and Outer Housing

The tubular lock consists of a central plug (the cylinder that rotates) housed inside an outer shell. The plug has a circular pin arrangement drilled around its perimeter.

2. Pins and Springs

Inside these drilled holes are spring-loaded pin stacks, each consisting of a bottom pin (key pin) and a top pin (driver pin). When at rest, these pins block the plug from turning because the pins straddle the shear line.

3. The Notch System

To prevent the key from inserting in any random orientation, both the key and the lock typically have a physical notch. These must align before the key can fully enter the cylinder.

4. Horizontal vs. Vertical Pin Movement

Unlike linear locks, tubular lock pins move horizontally—radially in and out from the center. This difference in pin orientation is the essence of what makes the tubular lock unique.

5. High-Security Variations

Some high-security tubular locks incorporate features like false cuts, additional pin stacks, or unique pin shapes to resist bumping and picking. However, many standard tubular locks, especially older models, are more vulnerable.

Common Places You’ll Find Tubular Locks

You might be surprised at how many places rely on tubular locks. Here are a few:

Vending Machines: Soda, snack, and candy machines often use tubular locks because they are compact and moderately resistant to casual tampering.

Bicycle Locks: Some bike U-locks and cable locks employ tubular mechanisms.

Coin-Operated Machines: Laundry machines, arcade games, and jukeboxes frequently use them.

Display Cases: Retail kiosks sometimes use small tubular locks for glass display doors.

This prevalence makes understanding these locks especially important for authorized personnel such as vending machine service technicians and locksmiths.

Tubular Lock Picking: An Essential Skill for Professionals

Before we explore the picking method, it’s vital to emphasize that lock picking should never be used for unlawful entry. Ethical and legal lock picking is a tool of the trade for locksmiths, maintenance workers, and security researchers. Unauthorized picking can lead to criminal charges.

How a Tubular Lock Pick Works

The tool most commonly used to pick a tubular lock is the tubular lock pick, like the popular SouthOrd pick. It is designed to mimic the way a tubular key interacts with the pins, but instead of preset cuts, the pick has adjustable needles.

Here’s how it works:

The pick has a set of thin, spring-loaded feeler needles arranged in a circle that correspond to the lock’s pins.

These needles press against the pins inside the lock.

As you apply gentle torque and slight movement, the needles adjust themselves to match the shear line depths, just like a real key would.

Step-By-Step: How to Pick a Tubular Lock

1. Prepare Your Tools

Have your tubular lock pick tool ready. Make sure the picking needles are aligned evenly with the tool’s guide ring, and the tension is set light.

2. Insert the Pick

Gently push the tubular pick straight into the keyway. The needles will press against the pins, pushing them inward.

3. Apply Gentle Torque and Movement

Rotate the pick slightly left and right while maintaining inward pressure. The goal is to encourage each needle to adjust its depth incrementally as the pins align to the shear line.

4. Feel for Feedback

Listen and feel for subtle clicks and changes in resistance. When the pins line up perfectly, the plug will rotate, and the lock will open.

5. Adjust and Retry If Necessary

If the lock doesn’t open after a few attempts, remove the pick, reset the needles, adjust the tension slightly tighter, and try again.

Best Practices for Success

Picking a tubular lock can be tricky for beginners. Here are some tips:

Practice with Transparent Models: Clear practice locks show you exactly what’s happening inside, speeding up your learning curve.

Use Light Tension: Too much tension will bind the pins and make picking harder.

Keep the Tool Straight: Wiggling too aggressively can bend the needles or damage the lock.

Understand the Lock: Some locks have security pins or tighter tolerances. The more you know the mechanism, the better your technique will be.

Are Tubular Locks Really Secure?

It’s worth noting that while tubular locks were once considered high-security, some models have vulnerabilities:

Common Key Sizes: Many older tubular locks share similar key depths, meaning a single key might open multiple locks.

Bypass Tools: Specialized bypass tools can open cheaply made tubular locks quickly.

Drilling: A last-resort destructive method is to drill out the lock—something professional locksmiths may do when non-destructive methods fail.

Modern designs often incorporate better tolerances, unique pin configurations, or anti-pick features to improve resistance.

Ethical Considerations and the Law

Let’s be clear: picking locks without permission is illegal in many jurisdictions. This guide is intended for:

Locksmith training

Security research

Authorized maintenance

Emergency situations when you are locked out of your own property

Always obtain permission before attempting to pick any lock you do not own.

The Historical Context of Tubular Locks

Tubular locks gained popularity in the mid-20th century as vending machines and coin-operated devices boomed. Their compact size, ease of use, and moderate resistance to tampering made them an industry standard.

Over the decades, the tools used to pick them have evolved alongside improvements in lock design. The introduction of better manufacturing tolerances and patented designs has forced tool makers to innovate as well.

This cat-and-mouse game between lock manufacturers and security testers has helped push the entire field of physical security forward.

Final Thoughts

Understanding how tubular locks work and how they can be picked is not about enabling wrongdoing—it’s about knowledge, preparedness, and security awareness. For locksmiths and security professionals, mastering tubular lock picking is an important part of providing reliable service.

If you own or manage equipment secured by tubular locks, consider whether your locks are up to date with modern security standards. Sometimes, upgrading to locks with higher pin counts, unique keyways, or electronic upgrades is the best defense against unauthorized access.

Locks, after all, are not just pieces of metal. They’re a testament to human ingenuity, the ongoing battle between security and compromise, and the trust we place in small devices to guard our property.