Essential Locksmithing Skills for 2026

Essential Locksmithing Skills for 2026

• Stator (Housing): The outer, stationary part of the lock cylinder that houses the plug.
• Shear Line: This is the critical line between the plug and the housing. When the correct key is inserted, it aligns all the pins at this line, allowing the plug to turn freely.
• Driver Pins: These are the upper set of pins, typically spring-loaded, that sit partially in the plug and partially in the housing when no key is inserted, preventing the plug from turning.
• Key Pins (Bottom Pins): These are the lower set of pins that directly interact with the key's bitting (the cuts on the key).
• Springs: Small springs located above the driver pins, pushing them downwards. When you insert a key, its unique cuts push the key pins upwards. If it's the correct key, it pushes the key pins and, in turn, the driver pins, to precisely the right height so that the break between the key pin and the driver pin aligns perfectly with the shear line. At this point, the driver pins are entirely in the housing, and the key pins are entirely in the plug, allowing the plug to rotate and unlock the mechanism. Any incorrect key will fail to align all the pins at the shear line, meaning some driver pins will still obstruct the plug's rotation. This fundamental principle is critical for understanding lock picking, rekeying, and basic troubleshooting. ### Common Lock Types You'll Encounter While the pin tumbler is prevalent, digital nomads will come across several other types of locks. Familiarity with these will enhance your preparedness. 1. Warded Locks: These are simpler locks, often found on older internal doors or basic padlocks. They have obstructions (wards) inside the lock that prevent incorrect keys from turning. The key has specific cuts or notches that bypass these wards. They offer very low security.

2. Disc Detainer Locks: Common in Scandinavia and increasingly elsewhere. These use rotating discs that align with the correct key. They are generally much harder to pick than pin tumbler locks. Keys for these often look flat with multiple 'bumps' or cuts along the edge.

3. Wafer Tumbler Locks: Similar in concept to pin tumblers but using flat wafers instead of pins. Often found on cabinets, vehicle ignitions, and cheaper padlocks. They offer moderate security and are generally easier to pick than pin tumblers.

4. Lever Locks: Primarily used in older buildings and safes, especially in the UK and Europe. These use a series of levers that must be lifted to a specific height by the key before the bolt can be retracted.

5. Smart Locks/Digital Locks: Increasingly common in modern apartments and hotels. These use keypads, fingerprints, RFID cards, or smartphone apps for access. While they don't involve traditional "picking," understanding their power sources, reset procedures, and manual override options is a crucial "locksmithing" skill for the modern era. We'll discuss these later in more detail in the context of Smart Home Security. By understanding the basic anatomy and function of these common lock types, you gain a significant advantage. You'll be better equipped to identify what you're dealing with, understand potential vulnerabilities, and appreciate the methods required to interact with them, whether for legitimate entry or basic repairs. This foundational knowledge is the cornerstone of all other locksmithing skills. For more information on securing your belongings, check out our guide on Travel Security Best Practices. ## Basic Lock Troubleshooting and Minor Repairs One of the most immediate benefits of having rudimentary locksmithing skills is the ability to diagnose and fix common lock issues without calling a professional. This can save time, money, and a great deal of frustration, especially when you're in an unfamiliar place like Hanoi or Mexico City. Many lock problems are surprisingly simple to resolve with a little knowledge and the right approach. ### Common Lock Problems and Solutions 1. Sticking or Stiff Locks: Cause: Dirt, grime, rust, or an accumulation of old lubricant can make a lock feel stiff or difficult to turn. Solution: Never use oil-based lubricants like WD-40 inside a lock cylinder, as they can attract more dust and gum up the mechanism over time. Instead, use a graphite-based lubricant or a silicon-based spray specifically designed for locks. Apply sparingly directly into the keyway, insert and remove the key several times to distribute the lubricant, and then clean the key. Tip: Carry a small tube of graphite lubricant in your Digital Nomad EDC Kit. 2. Key Breaks Off in the Lock: Cause: Worn-out keys, excessive force, or a stiff lock can cause a key to snap, leaving a piece lodged in the keyway. Solution: This requires patience. If a piece of the key is still slightly protruding, try to grip it with needle-nose pliers or strong tweezers. If it's flush or recessed, a broken key extractor tool (a thin, barbed hook) is ideal. Insert the extractor hook-side up, gently slide it past the broken piece, turn it slightly to hook onto a groove or bitting, and slowly pull out the fragment. Avoid pushing the fragment further in. Precaution: Get duplicate keys made before they become too worn. 3. Key Worn Down or Bent: Cause: Regular use degrades keys, smoothing out the bitting or bending the shaft. Solution: A worn key may not lift the pins to the correct height. If you have a working spare, compare them. If the key is bent, place it on a flat, hard surface and gently tap it with a soft hammer or another object to straighten it. If it’s significantly worn, it’s best to get a new duplicate made from the original or a working spare. 4. Door Latch Stuck (Door Won't Close Firmly): Cause: The latch bolt (the part that springs out of the door edge) might be sticking, or the strike plate (the metal plate on the door frame) might be misaligned. Solution: First, check the screws on the latch mechanism; sometimes they loosen. Lubricate the latch bolt assembly where it enters the door. If the issue is misalignment, the strike plate might need minor adjustment. Loosen the screws, reposition it slightly, and retighten. Mark the current position with a pencil first so you can revert if needed. 5. Loose Door Knob or Handle: Cause: Screws securing the knob assembly loosen over time with consistent use. Solution: Most door knobs have either visible screws on the rose plate (the circular base) or hidden screws that require prying off a cover plate to access. Simply tighten these screws. For levers, there's often a small Allen key grub screw on the underside that secures the lever to the spindle. Tighten this. ### Essential Tools for a Nomad's Repair Kit Carrying a compact kit of basic tools can make a huge difference. * Small Screwdriver Set: Both Phillips and flathead, often found in multi-tools.

• Needle-Nose Pliers/Tweezers: Invaluable for extracting broken keys or handling small parts.
• Graphite or Silicon Lock Lubricant: A small tube or spray can.
• Broken Key Extractor Set: Small, specialized tools that are highly effective.
• Small Pry Tool (Non-marring plastic preferred): For removing cover plates.
• Allen Key Set: For various handle and lock assemblies.
• Small Flashlight/Headlamp: For working in low light conditions. These small, lightweight tools can easily fit into a Digital Nomad Backpack and will equip you to handle a surprising number of common lock issues. Knowing how to perform these minor repairs not only saves money but also fosters a sense of self-sufficiency that is invaluable for anyone living a nomadic lifestyle. It's about being prepared, whether you're renting an apartment in Berlin or a bungalow in Da Nang. ## Non-Destructive Entry Techniques for Emergency Access While we certainly don't advocate for breaking into properties illegally, understanding non-destructive entry (NDE) techniques is a critical skill for responsible digital nomads. This knowledge is purely for emergency self-access circumstances – for instance, when you've accidentally locked yourself out of your own rented apartment or temporary workspace, and have no other means of entry. The goal is to regain access without causing damage, which would otherwise incur significant costs and potential trouble with landlords. This section focuses on very basic, widely understood techniques for common locks, emphasizing ethical use. ### Lock Picking Fundamentals (Pin Tumbler Locks) The ability to pick a basic pin tumbler lock is perhaps the most iconic locksmithing skill. It's a nuanced process that requires patience, a light touch, and an understanding of the lock's internal mechanics. #### Tools:
• Tension Wrench (Torsion Wrench): Applies rotational pressure to the lock cylinder, creating a binding effect on the pins. This is crucial for successful picking.
• Pick Set: A variety of picks, but for beginners, a hook pick (for single pin picking) and a rake pick (for scrubbing or raking) are most useful. #### The Process (Single Pin Picking - SPP):

1. Insert Tension Wrench: Apply light, consistent rotational pressure in the direction the key would turn to unlock it. This pressure causes the driver pins to bind slightly against the plug.

2. Insert Hook Pick: Slide the hook pick into the keyway, past all the pins, to the back.

3. "Feel" for the Binding Pin: Gently lift each pin. One pin will feel "stuck" or "binding" more than the others; this is your binding pin.

4. Set the Pin: Apply slight upward pressure with the pick to the binding pin until you feel a tiny "click" or a slight give in the tension wrench. This indicates the driver pin has been lifted past the shear line and dropped onto the shelf created by the plug's rotation.

5. Find the Next Binding Pin: Maintain tension and repeat the process, going through each pin one by one. As each pin is set, the plug will rotate minutely, bringing a new pin into the binding position.

6. Rotate and Unlock: Once all pins are set, the plug will rotate freely, allowing you to unlock the door. #### The Process (Raking):

Raking is a faster, less precise method, often effective on lower-security locks.

1. Insert Tension Wrench: Same as SPP, apply light tension.

2. Insert Rake Pick: Slide a rake pick (like an 'L' rake or a 'city' rake) all the way into the keyway.

3. Rake Out: While applying consistent light tension, quickly rake the pick out and in, up and down, cycling through the pins multiple times. This mimics the key's action of randomly lifting pins.

4. Listen and Feel: You're trying to "bounce" the pins into place. With practice, you might feel the plug turn slightly. #### Ethical Considerations and Practice:

• Legality: Always pick locks you own or have explicit permission to pick. Practicing on your own padlocks or specific practice locks is essential. Never attempt to pick a lock that isn't yours.
• Purpose: This skill is for self-reliance in emergencies, not illicit activities. Misusing these skills can have serious legal consequences.
• Practice Locks: Purchase transparent practice locks or standard padlocks to get a feel for the pins and the shear line. This is invaluable. Search for "lock picking practice kits" online. ### Bypass Techniques (for Simpler Locks) Some cheaper locks or specific lock designs can be opened without traditional picking. 1. Shimming Padlocks: For laminated or combination padlocks, shims (thin pieces of metal) can often be inserted between the shackle and the lock body to disengage the locking pawl. This works best on padlocks that aren't "double-locked" or have anti-shim features. Look for padlock shims online.

2. Credit Card/Plastic Card Bypass (Spring Latch Locks): This classic method works on spring-loaded door latches that aren't deadbolted. Slide a stiff plastic card (like a hotel key card, not your credit card!) into the gap between the door and the frame, above the latch. Angle the card towards the handle. Wiggle the card firmly, applying pressure to the slanted edge of the latch bolt, pushing it back into the door. Simultaneously push or pull the door. This often requires a strong, quick motion. This method is effective when the door opens inward but can also work with outward-opening doors depending on the latch design. ### Essential Mindset for NDE * Patience: Lock picking is rarely quick, especially for beginners. Don't get frustrated.

• Light Touch: Force is counterproductive. Listen and feel for subtle cues.
• Practice: Like any skill, it improves with consistent practice.
• Ethical Foundation: Always remember the purpose of learning these skills – self-reliance and legitimate access, never for malicious intent. By responsibly acquiring these non-destructive entry skills, a digital nomad adds an invaluable layer of independence and problem-solving capability to their repertoire, ensuring they are never truly locked out, always with a legitimate and ethical approach. For more on safety while traveling, consider our guide on Personal Safety for Digital Nomads. ## Key Duplication and Management on the Go Managing keys effectively is a fundamental part of responsible living, especially when moving between different accommodations and environments as a digital nomad. The need for a duplicate key can arise unexpectedly, whether you've lost your only copy, or simply need an extra for a trusted friend or colleague. Understanding the nuances of key duplication and developing a smart key management strategy are essential skills for life on the move. ### Understanding Key Duplication Challenges and Solutions Key duplication is not always as straightforward as it seems, particularly in foreign countries where different lock standards and regulations apply. 1. Proprietary Keys: Many modern locks, especially in apartment buildings or high-security commercial spaces, use restricted or proprietary keys. These keys often have "Do Not Duplicate" stamped on them or are protected by patents. To get a duplicate, you typically need to show proof of ownership or authorization, and the blank keys are only available through authorized locksmiths, often from specific manufacturers such as Medeco, Schlage Primus, or Mul-T-Lock. Solution: If you encounter such a key, your options are limited. You'll need to contact your landlord or accommodation provider to arrange a duplicate through their official channels. This can be time-consuming and might incur a fee. Tip: Always clarify key duplication policies before signing a lease or renting an apartment. 2. Standard Keys: For most common locks (e.g., standard pin tumbler locks on older homes, padlocks), duplication is simpler. Process: Take your key to a local hardware store or a locksmith shop. They use key cutting machines that trace the bitting of your original key onto a blank. Quality Check: Always test the new duplicate key thoroughly in the lock before leaving the store. Sometimes, small imperfections in the cutting can prevent it from working smoothly. A good locksmith will often test it for you. Finding a Key Cutter: Ask locals for recommendations, or use online maps to find "cerrajería" (Spanish), "serralheiro" (Portuguese), "tukang kunci" (Indonesian), or "Key Cutting" in English. 3. Electronic Keys/FOBs: These are increasingly common for building access, especially in co-working spaces or modern apartment complexes. Duplication Challenge: Duplicating these often requires specialized equipment and permissions. Some older RFID cards can be "cloned" using aftermarket devices, but this is often against building policy and can be unreliable. Newer, encrypted systems are much harder to duplicate without official channels. Solution: For electronic keys, you almost always need to go through the building management or landlord. Understand their policies for lost or damaged fobs. ### Smart Key Management for Nomads A thoughtful strategy for key management can prevent many headaches. 1. The "Emergency Spare" Principle: For physical keys: Have at least one spare created. Leave this spare with a trusted person (a friend, a co-worker in the same city, or even a landlord if they offer a secure service). Avoid leaving a spare key hidden under a mat – that's the first place thieves look! For digital keys (codes): Keep a written or digital backup of access codes in a secure, encrypted location (e.g., a password manager like LastPass or 1Password, not just a note on your phone). Ensure a family member has access to this information in an absolute emergency. 2. Key Identification: Avoid Labels: Never label your keys with your address or apartment number. If lost, this immediately compromises your security. Coded System: If you must identify them, use a non-obvious coded system (e.g., "Paris Apt 1," "Home," "Office" – but know what each refers to without a legend). 3. Consolidate and Declutter: Carry only the keys you need for your current location. If you're in Kyoto and your keys for a previous rental in Rome are still on your keyring, remove them. Consider a compact key organizer to prevent keys from jingling or getting tangled in your bag. 4. Reporting Lost Keys: If you lose keys for a temporary accommodation, inform your landlord or host immediately. They may have procedures for replacement or rekeying, which might come with a cost but is often necessary for security. Understand the potential costs involved. Some places charge significant fees for lost keys, especially if rekeying is required. 5. Digital Backups for Physical Keys (Conceptual): While you can't "duplicate" a physical key digitally, you could theoretically photograph the bitting pattern (if it's not a restricted key) and save it securely. In an emergency, a locksmith might be able to cut a new key from the photo, but this is highly dependent on the locksmith, local laws, and the quality of the image. It's a last-ditch option, not a primary strategy. This approach is more for historical record than for practical, immediate duplication. Effective key management is about being proactive rather than reactive. By understanding how to duplicate common keys, respecting restrictions on proprietary ones, and implementing a smart storage and backup strategy, digital nomads can minimize the stress and security risks associated with losing or needing extra keys. This skill integrates well with overall Digital Nomad Safety considerations. ## Basic Rekeying and Lock Installation While often seen as a professional skill, basic rekeying and lock installation are surprisingly accessible for common residential locks. For a digital nomad, these abilities offer significant advantages: enhancing security in a temporary dwelling, troubleshooting difficult locks, or even helping out a fellow nomad or a local contact. Learning these skills adds another layer to your self-sufficiency toolkit, especially beneficial in situations where a local locksmith might be expensive or difficult to find. ### Understanding Rekeying Rekeying a lock means changing the internal pins so that the old key no longer works, and a new key does. You don't replace the entire lock body, just the cylinder's internal components. This is far cheaper and less labor-intensive than replacing the whole lock. #### When Rekeying is Useful for a Nomad:
• Enhanced Security: Moving into a new rental, especially an older one, there's always a question of who else might have keys. Rekeying (with landlord permission) gives you peace of mind that only your new keys will work.
• Lost Keys: If you lose a key and are concerned about security, rekeying is often the quickest solution.
• Standardizing Keys: If you have multiple locks (e.g., front door, back door, shed) and want them all to operate on a single key – this is called "master keying" or "keying alike." For a temporary home office, this can be a convenience. #### The Basic Rekeying Process (Pin Tumbler Lock):

This process primarily applies to common residential door knobs and deadbolts. 1. Remove the Lock Cylinder: * Carefully detach the lock from the door. This usually involves removing a few screws from the interior side of the door. For deadbolts, you'll slide out the cylinder. For doorknobs, you might need to disassemble the knob assembly to access the cylinder.

2. Disassemble the Cylinder: Locate the "retaining clip" or "C-clip" on the back of the cylinder plug. Use a small flathead screwdriver or a pick to gently remove it. Carefully insert the original working key into the cylinder. This aligns the key pins at the shear line. Gently pull the plug out of the cylinder housing. Do this over a clean, flat surface to catch any springs or pins.*

3. Change the Pins: With the old key still in the plug, you'll see the key pins flush with the top of the plug. Remove the old key pins (they might just fall out). Note the lengths and positions. Insert your new key into the plug. Using a rekeying kit (which contains various sized pins and a pin "tweezers" tool), select new key pins that, when inserted into the plug with the new key, sit perfectly flush with the top of the plug – exactly at the shear line. Once the new key pins are in, you'll need to drop the driver pins and springs into the housing. This is the trickiest part, often done with a "follower bar" that pushes the old driver pins out while keeping the springs compressed, allowing you to insert the new key-pin-filled plug. Some kits include a follower bar.

4. Reassemble and Test: Carefully slide the plug back into the cylinder housing. Replace the retaining clip. Test the new key multiple times in the rekeyed cylinder to ensure smooth operation before reinstalling it on the door. Crucially, the old key should now not work. #### Essential Tools for Rekeying:

• Screwdriver Set: Phillips and flathead.
• Rekeying Kit: Includes various size key pins, driver pins, springs, followers, and pin tweezers.
• Retaining Clip Pliers (optional but helpful): For C-clips.
• New Keys (blanks): Cut to your desired bitting. Note: Always get permission from your landlord or property owner before attempting to rekey a lock in a rental property. Unauthorized modifications could lead to significant penalties. ### Basic Lock Installation (Deadbolts and Door Knobs) Installing a new lock or replacing an existing one is a common DIY task. For a digital nomad, this might come in handy for:
• Upgrading security on a long-term rental (with permission).
• Installing a new lock on internal office doors in a self-rented co-living/co-working space.
• Helping a local friend. #### Key Steps for Installing a Standard Deadbolt: 1. Positioning: Choose an appropriate height, usually 6-12 inches above the doorknob.

2. Marking Holes: Use the provided template (if new door) or trace around the existing holes (if replacing). You'll need two main holes: The cross bore (2-1/8 inch diameter) through the face of the door for the cylinder. The edge bore (1 inch diameter) through the edge of the door for the latch bolt.

3. Drilling: Use a hole saw and drill bits for the precise diameter holes. Be careful to drill straight and accurately. Drill partially from each side to prevent splintering.

4. Install Latch Bolt: Slide the latch mechanism into the edge bore. Screw it into place. Ensure it functions smoothly.

5. Install Deadbolt Cylinders: Insert the exterior and interior cylinders through the door, align them with the latch, and secure them with the long through-bolts or screws provided.

6. Install Strike Plate: Close the door and mark where the deadbolt plunger hits the door frame. Chisel out a recess for the strike plate and screw it into place. Ensure the bolt extends fully into the plate when locked. #### Considerations:

• Door Type: Always verify the type of door (wood, metal, hollow core) before drilling.
• Tools: You'll need a power drill, hole saw, various drill bits, chisels, tape measure, and screwdrivers.
• Safety: Wear safety glasses. By gaining proficiency in basic rekeying and lock installation, you not only improve your immediate living situation but also build valuable practical skills for life on the road. These abilities, especially when coupled with knowledge of DIY Home Improvement for Nomads, contribute significantly to self-reliance and adaptability. ## Digital Access and Smart Lock Solutions The of locks is rapidly evolving beyond traditional mechanical systems. For the digital nomad, understanding and manipulating smart locks and digital access control systems is becoming just as important as knowing how to pick a pin tumbler. From Airbnb keypads to co-working space RFID readers, these technologies are everywhere, and knowing how to troubleshoot, reset, or even securely manage them is an essential contemporary locksmithing skill. This section will into the practicalities of digital access solutions. ### Types of Digital Access Systems You'll Encounter 1. Keypad Locks: Require a numerical code for entry. Common in vacation rentals, private residences, and offices. Pros: Keyless entry, easy code sharing (and revocation), no lost keys. Cons: Codes can be guessed or shared improperly, battery reliance, potential vulnerability to brute-force attacks (if not designed well). Nomad Skills: Code Management: How to change codes, create temporary codes for guests/cleaners, and delete old ones. This is usually done either directly on the keypad or via a smartphone app. Battery Replacement: Knowing how to access the battery compartment and replace batteries (often AAA or AA) before they die. Basic Troubleshooting: What to do if the keypad isn't responding (check batteries, reset procedures). Manual Override: Most have a physical key override – always know where it is and have access to the key. 2. RFID/NFC Card or Fob Readers: Used with access cards or small key fobs. Prevalent in hotels, co-working spaces, and apartment buildings (e.g., in Dubai or Singapore). Pros: Quick and easy access, difficult to duplicate without specialized equipment. Cons: Cards/fobs can be lost or demagnetized, reliance on backend system for programming. Nomad Skills: Activation/Deactivation: Understanding how to get new cards activated (usually through building management). Troubleshooting: What to do if your card isn't registering (check for damage, report to management). Security: Be mindful of where you keep your card; a lost card is a security risk. 3. Biometric Locks (Fingerprint/Facial Recognition): Less common in general rentals but growing for personal use and high-security areas. Pros: Ultimate keyless convenience, very difficult to bypass. Cons: Can be temperamental with dirty fingers, issues with registration, higher cost. Nomad Skills: Enrollment: How to enroll and delete fingerprints/faces. Backup Access: These must have alternative access methods (keypad, physical key) in case of sensor failure or user error. Know how to use them. Cleaning: Keeping the sensor clean for optimal performance. 4. Smartphone-Controlled Locks (Bluetooth/Wi-Fi): Popular for smart homes and modern rentals, often integrated with apps like August, Schlage Encode, Yale Assure. Pros: Remote access, detailed activity logs, geofencing capabilities. Cons: Reliance on phone battery, internet connection (for Wi-Fi models), app glitches, cybersecurity risks. Nomad Skills: App Management: Proficiency with the specific lock's app – granting/revoking access, checking logs, updating firmware. Connectivity Troubleshooting: What to do if Bluetooth isn't connecting, or Wi-Fi is down. Battery Monitoring: Most apps provide battery alerts – pay attention to them. Cybersecurity Basics: Using strong passwords for accounts, being wary of public Wi-Fi when controlling locks. This ties into broader Cybersecurity for Digital Nomads discussions. ### Practical Advice for Nomads with Digital Locks Always Know Your Backup: For any digital lock, identify the physical key override* (if one exists) and know its location. For keypad locks, write down the code in a secure place.
• Battery Awareness: Digital locks rely on power. Carry spare batteries for common types (AA/AAA) or be aware of the nearest place to buy them. Pay attention to "low battery" warnings and replace proactively.
• Documentation: Review the user manual for unfamiliar digital locks found in your rentals. Take photos of reset buttons or specific instructions if provided by the host.
• Temporary Codes: When managing a rental or a shared space, always use temporary or guest codes that can be easily deactivated after someone leaves. Never give out a permanent primary code.
• Security for Smart Locks: Treat your smart lock app like any other critical security app. Use two-factor authentication if available, and keep your phone and operating system updated. The transition to digital and smart lock technologies requires a shift in "locksmithing" skills from mechanical dexterity to digital literacy and cybersecurity awareness. For the modern nomad, being adept at managing these systems ensures both convenience and security, making them a crucial part of navigating temporary living arrangements around the globe. This evolving skill set means staying current with technology, which is a key trait for any Future-Proof Digital Nomad. ## Security Audits for Temporary Dwellings One of the most powerful locksmithing-adjacent skills for a digital nomad is the ability to conduct a basic security audit of any temporary dwelling. When you move into an Airbnb in Chiang Mai, a co-living space in Bali, or a serviced apartment in London, you inherit its existing security vulnerabilities. Being able to quickly assess these and make minor, permissible improvements can significantly enhance your safety and peace of mind. This isn't about paranoia, but about proactive common sense. ### The Nomad's Security Audit Checklist Follow these steps upon arrival, typically before unpacking or settling in completely. 1. Examine All Entry Points (Doors): Main Entrance Lock(s): Type: What kind of lock is it? Is it a basic spring latch, a deadbolt, or a smart lock? Deadbolts offer significantly more security than spring latches alone. Condition: Does the lock feel solid? Is there any visible damage to the lock body or keyway? Does the door frame around the lock show signs of forced entry (splintered wood, damaged metal)? Key Play: When the door is locked, how much "play" is there in the key? A lot of wiggle room can indicate worn cylinders. Strike Plate: Is the strike plate (on the door frame) securely screwed in? Is it a flimsy plate or a reinforced metal one? If possible, check the length of screws – longer screws (3 inches or more) anchor into the door frame stud, providing much better resistance against kicking in. Secondary Doors (Back Door, Balcony Door): Apply the same checks. Often, these are less secure than the main entrance. *