How Padlocks Work

How Padlocks Work

    How Padlocks Work


    Learn about the standard iron padlock to understand the main parts, how they work and also how to bypass the mechanical security features to pick the lock.

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    Padlocks come in many shapes colours and sizes. They have been around for hundreds of years, ranging in complexity of design by different people and civilisations depending on the technology and manufacturing processes they had available. With the industrial revolution came the mass-produced padlock which eventually settled on a pin tumbler design. Called so because inside are some pins and a barrel which rotates or tumbles over.

    These are strong mechanical locks which are easy to mass produce and we find them used for everything from keeping our bikes where we left them to symbolising the everlasting love between two people on a bridge, and then throwing the key away to ensure it can’t be undone. But these types of locks, especially the cheap ones, can be unlocked without a key if you know the correct method and once we understand how the lock works we’ll learn how to pick the lock.

    When we look at a padlock the most noticeable feature is the U-shaped shackle at the top. In the unlocked position, one end of the shackle pops out of the main body allowing this component to rotate freely. On the inside surface of the shackle we will find two notches. These form part of the lock mechanism and we’ll see that part shortly.


    To lock the brass padlock we simply align the end of the shackle with the hole in the lock body and push these together. You’ll feel the internal locking mechanism engage and click into place, the shackle will now be unable to leave the body of the lock. To unlock the padlock we need to insert the correct key into the key hole at the bottom of the lock body, and rotate the key until it releases the shackle.

    When the key is turned, the plug will rotate. The plug has a number of holes in the top, within each hole there is a small metal cylinder known as a key pin. Each key pin is a different height, and this will correspond to the profile of the key.

    When a key is inserted into the lock, the key pins will follow the profile of the key and move up and down until the key is fully inserted. Once fully inserted, if the correct key has been used, then the top of each key pin will align with the shear line. The driver pins will have been pushed up and will now fully sit within the housing while the key pins sits fully within the plug. This means the plug is now able to rotate. If the wrong key is inserted then the pins will not align and the plug will be unable to rotate.

    The key is inserted into the plug. The different sized key pins rest inside a number of holes inside the plug and will move up and down to follow the profile of the key. If the correct key is inserted then the top of the key pins will align with the top of the plug. This pushes the driver pins out of the plug holes and into their respective chamber. The springs ensure the driver pins will be forced into the holes if the wrong key, or if no key, is inserted.

    With all the pins cleared, the key can rotate the plug. At the end of the plug is a cam which also rotates with the plug. This connects with the arms of the two latches. The latches are pushed outwards by a spring, this pushes the arm against the cam but also pushes the latch into a notch on the shackle preventing the lock from opening without the key. With the correct key inserted the plug is free to rotate, this rotates the cam which pulls the latches inwards against the spring, releasing the shackle. A spring within the shackle chamber pushes the arm outward releasing the lock.


    Nowadays, there are many gifts you can give your loved ones. Often, you wonder what to give that special someone to let them feel that you love them forever. Perhaps a love padlock engraved with a message would work.

    Engraved padlocks are the new trend and are available for you online on Amazon, or you can visit your local gift shop. Love locks are excellent symbols of commitment to a lover, a friend, family, e.t.c. They are a perfect way to express to someone what they mean to you.

    Traditionally, people hang the padlocks on bridges, but you may have other creative ideas. However, some lovelocks do not come with keys. They symbolize locking your love forever. Here are a few engraved padlocks you can consider.

    Let us begin,

    40mm Personalized Engraved Love Lock


    The solid brass 40mm engraved disc padlock is a beautiful design with a permanent message engraved in bold letters. You can see the writings under most lighting conditions.

    It comes with an attractive, black gift box, whose price is overall. It is easily customizable according to your tastes and preference. The gift box also has engravings of your liking, and the letters come with a unique design. You can also look for ones on Amazon with the message you want or place an order with the exact specifications you need. You can also visit your nearby gift shop and select or order one from the manufacturer.

    The engraved love lock has a shiny brass color on the top area and a golden color on the bold writings. It comes with a pair of functional keys which resemble the tri-circle padlock design. The 40mm engraved love lock is an ideal gift for father’s day, mother’s day, birthday parties, wedding anniversaries, valentines, e.t.c.

    Long Shackle lovelock Double Shaped Heart


    It comes in many exciting colors such as pink, red, blue, purple, e.t.c. The long shackle would be a lovely present for someone who loves colorful items. You can also order the color you like with the message of your liking engraved on it. There is a gift box available which you can also personalize with a message.

    The long shackle engraved padlock does not have a key, so on one end, it has a small colored rubber or plastic seal for decoration. The large latch is ideal for hanging on a bridge with your loved ones.

    It is an excellent gift for colorful occasions such as weddings, Valentine’s day, birthdays, e.t.c. It has a heart-shaped design that captures the essence of love once you set your eyes on it. You can order it online on Amazon or any gift shop outlet available to you.

    Bird pink 4 Digit Combination Love Lock


    It has a unique and stunning combination of colors. It can get personalized with paintings of your choice to make it more customizable. The material of the love lock is alloy steel and stainless steel that makes it high security. The four-digit combination makes up for the keys, for you can unlock it automatically using the password you set.

    It is ideal for locking gym lockers, luggage, sheds, gates, e.t.c. You can personalize it by engraving it with a message to a friend, family, or spouse. You can make a few clicks online and order it from Amazon or visit your nearby gift shop to get a customizable one.

    Engraved love lock Necklace


    Engraved Padlocks come in a variety of designs ranging from chokers to necklaces and chains. The pendant can be heart-shaped, square, rectangle, or any personalized shape you want. Gifting a love lock necklace engraved with a message is a thoughtful idea. You can also hang it on bridges if you prefer memorable romantic moments.


    An engraved golden heart necklace might be just the thing your spouse needs if he/she likes fancy necklaces. You can purchase them on Amazon or your local jewelry or gift shop.

    Heart Engraved PadLock and Key Set


    These charming engraved heart lock engraved laminated padlock will melt your heart once you set your eyes on them. They have the most romantic message engraved on them. You can easily customize them with the type of message you want. In most cases, the message will either be just what you wanted to convey or will be beyond your expectations. They also come in the most endearing colors, light pink, shiny grey, silver, gold, e.t.c.


    The product is a perfect wedding and couple gift since it comes with a wedding card box. These pretty love locks are available on Amazon, or you can check them out at your nearby gift shop.

    Iron Antique Vintage Engraved Love Lock


    The Iron Antique Vintage Engraved padlock is also called the “love rock”. It’s common among couples, sweethearts, love birds who usually lock it on a bridge, tree, gate, and other placements to symbolize their love.

    The interest in love padlocks has spiked since the turn of the century as more people look for different ways to express their love to each other. The vintage love lock features a customized engravement on individual pieces. Some versions have rustic textures to highlight how long both individuals have been together.

    You can buy the Iron Antique Vintage Engraved Padlock as a gift to your special friend through online platforms such as Etsy. The engraving gives a personal touch to the item added to the lock includes two skeleton keys (one for each partner).

    Silver-Tone Heart- Shaped Love Lock


    The silver Tone Heart Shaped love lock gestures a love-shaped design coupled with a personalized engraving on its surface. You can opt for a name, quote, verse, etc. The product also comes with a key for unlocking.

    The engraved weatherproof padlock comes in a dominant silver-white color, sleek design measuring between 1.75” by 1.40” by 4.0” in height. You can also purchase the product enclosed in a gift box and a bow ribbon for a more personalized touch. The Silver Tone Heart Shaped love lock is suited for gifts, birthday presents, and on special occasions.

    Vintage Copper Engraved Padlocks


    Copper love locks have existed for a long time. These love locks come off as extremely durable, safe, and highly customizable. You can purchase the products from online stores such as Amazon and eBay or at antique stores. It becomes even more meaningful when you gift it to your spouse, loved one, or friend.

    Vintage copper gives off a rustic look that seems to transcend the realms of time. It has an old-school feeling and might feature other unique properties such as the shape of the keys and the overall aesthetics of the engraved padlock.

    Bottom Line:

    Engraved padlocks are unique locks in every aspect. In contrast to standard versions, they provide a special message and give off a personalized feel to the product.

    Engraved padlocks are perfect gifts for occasions such as graduations, valentine’s day, birthdays, engagements, wedding ceremonies, marriage anniversaries, etc. I am sure you will agree with me that before adopting extravagant decisions, such as locking up stuff with them, a gift like an engraved padlock from someone would be something you would treasure.