Home Improvement

DIY: Mastering Cylinder Door Lock Fitting

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Many homes choose cylinder locks because they are well-known for being simple to install. Still, for those who are unfamiliar with them, starting the process of fitting or altering one may seem way too difficult. So this guide will walk you through the steps of installing a cylinder lock, including what equipment you’ll need and how to do it properly.

Cylinder lock mechanism in short

Cylinder locks, also known as pin tumbler locks, operate on a simple yet effective mechanism. The lock consists of a series of pins that align with the unique pattern of the key. When the key is inserted into the lock, each pin moves into its designated position, allowing the key to turn and either lock or unlock the door. That’s it, simple, right?

There are two main types of cylinder locks on the market today:

  • Euro cylinder locks – They resemble a large keyhole or, to some, a lightbulb shape. Euro cylinder locks are available in different configurations offering one or two-sided key operation. Still, despite varying models, all Euro cylinder locks share the same size and scale. The differences lie in the length of the cylinders, the position of the moving “cam,” and the location of the fastening screw-hole. These are widely adopted in the UK due to their practicality, especially with the prevalence of uPVC and Composite doors.
  • Oval cylinder locks – Oval-shaped, providing a distinct appearance, these are similar to Euro cylinder locks and also function based on the key’s pattern; Oval cylinders are available in single-cylinder or double-cylinder options based on specific needs. They are less common in the UK today, with other lock types being more prevalent.

Can you change lock cylinder by yourself?

Yes, changing a lock cylinder can be a great DIY task, but it requires specific skills and considerations. Do you have what it takes to fit a cylinder lock? You need to:

  • Be skilled in using common tools such as screwdrivers, pliers, adjustable wrenches and the like;
  • Have basic knowledge of lock components;
  • Have the ability to pay close attention to details during the lock replacement process;
  • Have proficiency in troubleshooting and solving issues that may arise during the lock replacement.
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Fitting a new cylinder door lock

Here’s a step-by-step guide along with the necessary tools for successfully fitting a new cylinder door lock. Ensure the tools are in good condition and appropriate for the type of door material you are working with (wood or PVC).

Necessary tools:

  • Pencil – for marking the position of the lock body and faceplate on the door;
  • Auger drill bit – specifically designed for wood, slightly wider than the lock body, for drilling holes;
  • Chisel – for chiselling out the space between drilled holes to accommodate the lock body;
  • Screwdriver – for installing backplate screws securely;
  • Drill – used for drilling holes for the lock cylinder and backplate screws.

And now…For PVC doors, existing fittings may suffice for installing or changing a cylinder barrel. If dealing with a wooden door, you’ll need the already mentioned auger drill bit, chisel, and screws.

This is how to fit a new cylinder lock on a wooden door:

  1. Mark the lock position – Use a pencil to accurately mark the position of the lock body on the door. Outline the entire shape of the lock, ensuring precision in its placement.
  2. Faceplate marking – Mark the location of the faceplate on the door’s edge, including the type and size of screws needed for secure attachment.
  3. Guideline drawing – After placing the faceplate, draw a straight and level line from the top hole to the bottom for accurate alignment of the lock components.
  4. Drill for lock body – Utilize an auger drill bit designed for wood, ensuring it’s slightly wider than the lock body. Drill a series of holes and chisel out the space between them. Specify the recommended depth for drilling to ensure the lock body fits properly.
  5. Check fit – Insert the lock body to check for a proper fit. If needed, chisel out additional material to ensure a snug fit. Verify that the lock body sits flush with the door surface.
  6. Drill for cylinder mechanism – Remove the lock body and drill holes for the lock cylinder, specifying the appropriate size of the drill bit and recommended depth.
  7. Backplate installation – Drill holes for the backplate screws and securely install the backplates. Provide details on aligning the backplate properly for a neat and professional finish.
  8. Insert cylinder mechanism – Lubricate the lock cylinder if necessary and insert it into the door from the outside, following any brand-specific instructions regarding the indicated side for the outside part of the door.
  9. Final check – Conduct a final check to ensure all components are securely in place and that the lock functions smoothly. Make any necessary adjustments for optimal performance.
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Changing an old cylinder lock

To start off the euro cylinder lock replacement…

  1. Measure the entire length of your current lock, including any protruding parts;
  2. Open the door to access the lock and proceed with the measurements;
  3. Use a standard flat-head or Phillips-head screwdriver to locate and interact with the centre screw on the lock mechanism;
  4. Gauge the distance between the centre screw and the face end of the lock on each side;
  5. Add up the lengths measured on both sides. Ensure precision by rounding up to the nearest millimetre.

Once you’re done with this part and you have purchased a new lock with the right dimensions, you can easily replace the euro cylinder lock. Here’s how:

  1. Begin by opening the door to access the lock mechanism;
  2. Locate and remove the lock fixing screw using the appropriate tool;
  3. Insert the key into the new lock and gently turn it on both sides. This action ensures that the cam tongue aligns with the body of the lock;
  4. Gently push and pull the lock. If the cam tongue is correctly aligned, you’ll be able to smoothly pull out the cylinder using the key. Troubleshoot if alignment is not correct;
  5. Position the new lock in place, ensuring it fits securely. Pay attention to any specific orientation or alignment instructions;
  6. Repeat all the steps in reverse order, securing the new lock in position. Double-check that the cam tongue is correctly aligned and functions smoothly;
  7. Before concluding, perform a final check to confirm that the cam tongue is correctly aligned and that the lock functions smoothly;
  8. Consider referring to simple diagrams or illustrations to accompany the steps, aiding users in understanding the process more visually.
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How do you know when a cylinder lock needs changing?

If you aren’t sure whether you should replace your cylinder lock just yet, then check these scenarios. If any of them right true, then you need to go forward with the refitting.

  • Difficulty in inserting or turning the key – Internal components may be worn, damaged, or corroded, affecting the lock’s functionality;
  • The lock feels loose or wobbles when the key is inserted – Wear on internal components, loose screws, or a damaged cylinder may also cause instability;
  • The key breaks off inside the lock – Fatigue, corrosion, or other factors can weaken the key, leading to breakage. If this occurs, it’s a clear indication that the lock is compromised and should be replaced to avoid potential security risks;
  • Visible wear and Tear – Exposure to the elements, age, or lack of maintenance can contribute to physical degradation leading to obvious signs of wear, rust, or corrosion on the lock exterior. That means the lock is weakened and a security risk;
  • Concerns about the lock’s security features – Advances in lock-picking techniques or an outdated lock model may pose security risks. A fine example is lock snapping which burglars always use on old locks. That’s why you should upgrade to a more secure lock or a model with enhanced features to better protect your property;
  • Loss or theft of keys – Unauthorised possession of keys can compromise home security. Change the lock immediately.

Upgrade your security with a new lock!

Your safety is our priority!

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Upgrade your security with a new lock!

Your safety is our priority!

Learn more

How much does it cost to change a euro cylinder lock?

The cost to change a euro cylinder lock can vary depending on several factors such as the type of lock, brand, security standard, and if any call-out charges are included in the cost. With that said here are some exemplary prices:

  • Basic euro-cylinder lock replacement for uPVC door starts from £24;
  • Standard euro cylinder lock replacement on uPVC door: Starts from £85;
  • uPVC door anti-snap euro cylinder lock replacement costs between £100 – £150 per lock;
  • Labour cost for lock replacement can be £60 to £75 per hour;
  • Euro cylinder lock by itself can cost from £10 to £35;
  • Emergency services may incur higher costs.

So, the overall cost to change an euro-cylinder lock ranges from £100 to £150. Prices change all the time because of many more factors than the ones already mentioned.

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  • There are two main types of cylinder locks – Euro cylinder locks and oval cylinder locks;
  • Changing a lock cylinder is a potential DIY task, but it requires specific skills;
  • If you have PVC doors, the current fittings might be suitable for installing or replacing a cylinder barrel. However, if you’re working with a wooden door, you’ll require the auger drill bit, chisel, and screws mentioned earlier
  • Before replacing your old cylinder lock, you need to measure it thoroughly to know what to buy next.
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